├── LICENSE ├── README.md ├── arty ├── client │ ├── build.sh │ ├── index.html │ ├── main.go │ ├── main.wasm │ └── wasm_exec.js ├── painter │ ├── assets │ │ └── font.ttf │ ├── font │ │ └── font.go │ ├── fontcache.go │ ├── operations.go │ └── painter.go └── server │ └── main.go ├── bittune ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js ├── bouncy ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js ├── bumpy ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js ├── go.mod ├── go.sum ├── hexy ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js ├── rainbow-mouse ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js ├── repulsion ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js ├── serve.go └── splashy ├── build.sh ├── index.html ├── main.go ├── main.wasm └── wasm_exec.js /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. 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We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright [yyyy] [name of copyright owner] 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # go webassembly experiments 2 | 3 | Requires go1.13 4 | 5 | - [bouncy](https://stdiopt.github.io/gowasm-experiments/bouncy) 6 | - [rainbow-mouse](https://stdiopt.github.io/gowasm-experiments/rainbow-mouse) 7 | - [repulsion](https://stdiopt.github.io/gowasm-experiments/repulsion) 8 | - [bumpy](https://stdiopt.github.io/gowasm-experiments/bumpy) 9 | - [splashy](https://stdiopt.github.io/gowasm-experiments/splashy) 10 | - [arty](https://stdiopt.github.io/gowasm-experiments/arty/client) 11 | - [hexy](https://stdiopt.github.io/gowasm-experiments/hexy) 12 | - [bittune](https://stdiopt.github.io/gowasm-experiments/bittune) 13 | 14 | ## Building and running 15 | 16 | ```sh 17 | $ cd {proj} # sub folder (i.e. bouncy, rainbow-mouse) 18 | $ go get -v # ignore the js warning 19 | $ ./build.sh 20 | $ go run ../serve.go 21 | ``` 22 | 23 | Serve with caddy or anything else that is able to set the mimetype 24 | 'application/wasm' for .wasm files 25 | -------------------------------------------------------------------------------- /arty/client/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /arty/client/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - canvas 4 | 5 | 21 | 53 | 54 | 55 | 56 |
57 |
58 | connecting... 59 |
60 |
61 | 62 |
63 |
64 | 6 65 |
66 | [source code] 67 |
68 | 69 | 70 | 71 | -------------------------------------------------------------------------------- /arty/client/main.go: -------------------------------------------------------------------------------- 1 | //Wasming 2 | // compile: GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 3 | package main 4 | 5 | import ( 6 | "encoding/json" 7 | "image/color" 8 | "log" 9 | "strconv" 10 | "syscall/js" 11 | 12 | "github.com/stdiopt/gowasm-experiments/arty/painter" 13 | 14 | "github.com/lucasb-eyer/go-colorful" 15 | ) 16 | 17 | func main() { 18 | c, err := NewCanvasClient("wss:/arty.us.hexasoftware.com") 19 | if err != nil { 20 | log.Fatal("could not start", err) 21 | } 22 | defer c.Close() 23 | c.Start() 24 | } 25 | 26 | type pos struct { 27 | x, y float64 28 | } 29 | 30 | type CanvasClient struct { 31 | done chan struct{} 32 | painter *painter.BufPainter 33 | addr string 34 | 35 | doc js.Value 36 | canvasEl js.Value 37 | ctx js.Value 38 | ws js.Value 39 | im js.Value 40 | // will hold js part of the image 41 | byteArray js.Value 42 | 43 | colorHex string 44 | lineWidth float64 45 | 46 | textOff pos 47 | lastPos pos 48 | width float64 49 | height float64 50 | } 51 | 52 | func NewCanvasClient(addr string) (*CanvasClient, error) { 53 | done := make(chan struct{}) 54 | 55 | painter, err := painter.New() 56 | if err != nil { 57 | return nil, err 58 | } 59 | return &CanvasClient{ 60 | done: done, 61 | painter: painter, 62 | addr: addr, 63 | lineWidth: 10, 64 | }, nil 65 | } 66 | 67 | func (c *CanvasClient) Start() { 68 | c.initCanvas() 69 | c.initFrameUpdate() 70 | c.initConnection() 71 | 72 | <-c.done 73 | } 74 | 75 | func (c *CanvasClient) Close() { 76 | close(c.done) 77 | } 78 | 79 | func (c *CanvasClient) initCanvas() { 80 | c.doc = js.Global().Get("document") 81 | c.canvasEl = c.doc.Call("getElementById", "mycanvas") 82 | c.width = c.canvasEl.Get("width").Float() 83 | c.height = c.canvasEl.Get("height").Float() 84 | c.ctx = c.canvasEl.Call("getContext", "2d") 85 | c.im = c.ctx.Call("createImageData", 1, 1) 86 | c.byteArray = js.Global().Get("Uint8Array").New(1 * 4) 87 | c.painter.OnInit = func(m painter.InitOP) { 88 | c.im = c.ctx.Call("createImageData", m.Width, m.Height) 89 | c.byteArray = js.Global().Get("Uint8Array").New(m.Width * m.Height * 4) 90 | c.SetStatus("connected") 91 | c.initEvents() 92 | } 93 | } 94 | 95 | func (c *CanvasClient) initFrameUpdate() { 96 | // Hold the callbacks without blocking 97 | go func() { 98 | var renderFrame js.Func 99 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 100 | c.draw() 101 | js.Global().Call("requestAnimationFrame", renderFrame) 102 | return nil 103 | }) 104 | defer renderFrame.Release() 105 | js.Global().Call("requestAnimationFrame", renderFrame) 106 | <-c.done 107 | }() 108 | } 109 | 110 | func (c *CanvasClient) initConnection() { 111 | go func() { 112 | c.SetStatus("connecting...") 113 | c.ws = js.Global().Get("WebSocket").New(c.addr) 114 | onopen := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 115 | c.SetStatus("receiving... (it takes some time)") 116 | return nil 117 | }) 118 | defer onopen.Release() 119 | onmessage := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 120 | c.painter.HandleRaw([]byte(args[0].Get("data").String())) 121 | return nil 122 | }) 123 | defer onmessage.Release() 124 | c.ws.Set("onopen", onopen) 125 | c.ws.Set("onmessage", onmessage) 126 | 127 | <-c.done 128 | }() 129 | } 130 | func (c *CanvasClient) initEvents() { 131 | go func() { 132 | // DOM events 133 | colorEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 134 | e := args[0] 135 | c.colorHex = e.Get("target").Get("value").String() 136 | return nil 137 | }) 138 | szEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 139 | e := args[0] 140 | v, _ := strconv.ParseFloat(e.Get("target").Get("value").String(), 64) 141 | c.lineWidth = v 142 | return nil 143 | }) 144 | defer szEvt.Release() 145 | 146 | c.doc.Call("getElementById", "color").Call("addEventListener", "change", colorEvt) 147 | c.doc.Call("getElementById", "size").Call("addEventListener", "change", szEvt) 148 | 149 | // Input events 150 | mouseDown := false 151 | mouseDownEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 152 | e := args[0] 153 | if e.Get("target") != c.canvasEl || e.Get("buttons").Float() != 1 { 154 | return nil 155 | } 156 | mouseDown = true 157 | if !e.Get("shiftKey").Bool() { 158 | c.lastPos.x = e.Get("pageX").Float() 159 | c.lastPos.y = e.Get("pageY").Float() 160 | c.textOff = pos{} // reset 161 | return nil 162 | } 163 | c.drawAtPointer(e) 164 | return nil 165 | }) 166 | defer mouseDownEvt.Release() 167 | 168 | mouseUpEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 169 | mouseDown = false 170 | return nil 171 | }) 172 | defer mouseUpEvt.Release() 173 | 174 | mouseMoveEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 175 | if !mouseDown { 176 | return nil 177 | } 178 | c.drawAtPointer(args[0]) 179 | return nil 180 | }) 181 | 182 | keyPressEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 183 | e := args[0] 184 | e.Call("preventDefault") 185 | key := e.Get("key").String() 186 | if key == "Enter" { 187 | c.textOff.x = 0 188 | c.textOff.y += (c.lineWidth + 10) 189 | } 190 | if len(key) != 1 { 191 | return nil 192 | } 193 | col, _ := colorful.Hex(c.colorHex) // Ignore error 194 | op := painter.TextOP{ 195 | color.RGBA{uint8(col.R * 255), uint8(col.G * 255), uint8(col.B * 255), 255}, 196 | c.lineWidth + 6, 197 | c.lastPos.x + c.textOff.x, c.lastPos.y + c.textOff.y, 198 | key, 199 | } 200 | c.textOff.x += (c.lineWidth + 10) * 0.6 201 | 202 | c.painter.HandleOP(op) 203 | buf, err := json.Marshal(painter.Message{op}) 204 | if err != nil { 205 | return nil 206 | } 207 | c.ws.Call("send", string(buf)) 208 | return nil 209 | 210 | }) 211 | defer keyPressEvt.Release() 212 | c.doc.Call("addEventListener", "mousemove", mouseMoveEvt) 213 | c.doc.Call("addEventListener", "mousedown", mouseDownEvt) 214 | c.doc.Call("addEventListener", "mouseup", mouseUpEvt) 215 | c.doc.Call("addEventListener", "keypress", keyPressEvt) 216 | 217 | <-c.done 218 | }() 219 | } 220 | func (c *CanvasClient) drawAtPointer(e js.Value) { 221 | lastPos := c.lastPos 222 | 223 | c.lastPos.x = e.Get("pageX").Float() 224 | c.lastPos.y = e.Get("pageY").Float() 225 | 226 | col, _ := colorful.Hex(c.colorHex) // Ignore error 227 | op := painter.LineOP{ 228 | color.RGBA{uint8(col.R * 255), uint8(col.G * 255), uint8(col.B * 255), 255}, 229 | c.lineWidth, 230 | lastPos.x, lastPos.y, 231 | c.lastPos.x, c.lastPos.y, 232 | } 233 | c.painter.HandleOP(op) 234 | 235 | buf, err := json.Marshal(painter.Message{op}) 236 | if err != nil { 237 | return 238 | } 239 | c.ws.Call("send", string(buf)) 240 | 241 | } 242 | func (c *CanvasClient) SetStatus(txt string) { 243 | c.doc.Call("getElementById", "status").Set("innerHTML", txt) 244 | } 245 | func (c *CanvasClient) draw() { 246 | // golang buffer 247 | // Needs to be a Uint8Array while image data have Uint8ClampedArray 248 | js.CopyBytesToJS(c.byteArray, c.painter.ImageData()) 249 | c.im.Get("data").Call("set", c.byteArray) 250 | c.ctx.Call("putImageData", c.im, 0, 0) 251 | } 252 | -------------------------------------------------------------------------------- /arty/client/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/arty/client/main.wasm -------------------------------------------------------------------------------- /arty/client/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | -------------------------------------------------------------------------------- /arty/painter/assets/font.ttf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/arty/painter/assets/font.ttf -------------------------------------------------------------------------------- /arty/painter/fontcache.go: -------------------------------------------------------------------------------- 1 | package painter 2 | 3 | import ( 4 | "github.com/golang/freetype/truetype" 5 | "github.com/llgcode/draw2d" 6 | ) 7 | 8 | type FontCache map[string]*truetype.Font 9 | 10 | func (f FontCache) Load(fd draw2d.FontData) (*truetype.Font, error) { 11 | font, ok := f[fd.Name] 12 | if !ok { 13 | return f["roboto"], nil 14 | } 15 | return font, nil 16 | } 17 | 18 | func (f *FontCache) Store(fd draw2d.FontData, tf *truetype.Font) { 19 | (*f)[fd.Name] = tf 20 | } 21 | -------------------------------------------------------------------------------- /arty/painter/operations.go: -------------------------------------------------------------------------------- 1 | package painter 2 | 3 | import ( 4 | "encoding/json" 5 | "errors" 6 | "image/color" 7 | ) 8 | 9 | const ( 10 | opInit = iota + 1 11 | opLine 12 | opText 13 | ) 14 | 15 | // OP Wrapper 16 | type Message struct { 17 | Payload interface{} 18 | } 19 | 20 | func (m *Message) UnmarshalJSON(raw []byte) error { 21 | v := struct { 22 | OP uint 23 | Payload json.RawMessage 24 | }{} 25 | err := json.Unmarshal(raw, &v) 26 | if err != nil { 27 | return err 28 | } 29 | switch v.OP { 30 | case opInit: 31 | payload := InitOP{} 32 | err = json.Unmarshal(v.Payload, &payload) 33 | m.Payload = payload 34 | case opLine: 35 | payload := LineOP{} 36 | err = json.Unmarshal(v.Payload, &payload) 37 | m.Payload = payload 38 | case opText: 39 | payload := TextOP{} 40 | err = json.Unmarshal(v.Payload, &payload) 41 | m.Payload = payload 42 | default: 43 | return errors.New("unknown operation") 44 | } 45 | return err 46 | } 47 | func (m Message) MarshalJSON() ([]byte, error) { 48 | v := struct { 49 | OP uint 50 | Payload interface{} 51 | }{ 52 | Payload: m.Payload, 53 | } 54 | switch m.Payload.(type) { 55 | case InitOP: 56 | v.OP = opInit 57 | case LineOP: 58 | v.OP = opLine 59 | case TextOP: 60 | v.OP = opText 61 | } 62 | return json.Marshal(v) 63 | } 64 | 65 | // This ops will be marshalled with the wrapper struct 66 | type InitOP struct { 67 | Width, Height int 68 | Data []byte 69 | } 70 | 71 | type LineOP struct { 72 | Color color.RGBA 73 | Width float64 74 | X1, Y1 float64 75 | X2, Y2 float64 76 | } 77 | 78 | type TextOP struct { 79 | Color color.RGBA 80 | Size float64 81 | X, Y float64 82 | Text string 83 | } 84 | -------------------------------------------------------------------------------- /arty/painter/painter.go: -------------------------------------------------------------------------------- 1 | //go:generate go get github.com/gohxs/folder2go 2 | //go:generate folder2go -nobackup assets font 3 | 4 | package painter 5 | 6 | import ( 7 | "encoding/json" 8 | "errors" 9 | "image" 10 | 11 | "github.com/golang/freetype/truetype" 12 | "github.com/llgcode/draw2d" 13 | "github.com/llgcode/draw2d/draw2dimg" 14 | "github.com/stdiopt/gowasm-experiments/arty/painter/font" 15 | ) 16 | 17 | type BufPainter struct { 18 | image *image.RGBA 19 | ctx *draw2dimg.GraphicContext 20 | font *truetype.Font 21 | fontData draw2d.FontData 22 | OnInit func(InitOP) 23 | } 24 | 25 | func New() (*BufPainter, error) { 26 | font, err := truetype.Parse(font.Data["font.ttf"]) 27 | if err != nil { 28 | return nil, err 29 | } 30 | return &BufPainter{font: font}, nil 31 | } 32 | 33 | func (p *BufPainter) HandleRaw(msg []byte) error { 34 | m := Message{} 35 | err := json.Unmarshal(msg, &m) 36 | if err != nil { 37 | return err 38 | } 39 | return p.HandleOP(m.Payload) 40 | } 41 | 42 | func (p *BufPainter) HandleOP(op interface{}) error { 43 | switch o := op.(type) { 44 | case InitOP: 45 | p.Init(o) 46 | case LineOP: 47 | p.Line(o) 48 | case TextOP: 49 | p.Text(o) 50 | default: 51 | return errors.New("unknown op") 52 | } 53 | return nil 54 | } 55 | 56 | func (p *BufPainter) Set(buf []byte) { 57 | if buf == nil { 58 | return 59 | } 60 | copy(p.image.Pix, buf) 61 | } 62 | 63 | func (p *BufPainter) ImageData() []byte { 64 | if p.image == nil { 65 | return nil 66 | } 67 | return p.image.Pix 68 | } 69 | 70 | func (p *BufPainter) Width() int { 71 | return p.image.Bounds().Max.X 72 | } 73 | 74 | func (p *BufPainter) Height() int { 75 | return p.image.Bounds().Max.Y 76 | } 77 | 78 | func (p *BufPainter) Init(op InitOP) { 79 | p.image = image.NewRGBA(image.Rect(0, 0, op.Width, op.Height)) 80 | 81 | // init font 82 | fontData := draw2d.FontData{ 83 | Name: "roboto", 84 | Family: draw2d.FontFamilySans, 85 | Style: draw2d.FontStyleNormal, 86 | } 87 | fontCache := &FontCache{} 88 | fontCache.Store(fontData, p.font) 89 | 90 | p.ctx = draw2dimg.NewGraphicContext(p.image) 91 | p.ctx.FontCache = fontCache 92 | 93 | p.Set(op.Data) // Image 94 | if p.OnInit != nil { 95 | p.OnInit(op) 96 | } 97 | } 98 | func (p *BufPainter) Line(op LineOP) { 99 | c := p.ctx 100 | c.SetStrokeColor(op.Color) 101 | c.SetLineWidth(op.Width) 102 | c.BeginPath() 103 | c.MoveTo(op.X1, op.Y1) 104 | c.LineTo(op.X2, op.Y2) 105 | c.Stroke() 106 | } 107 | func (p *BufPainter) Text(op TextOP) { 108 | c := p.ctx 109 | c.SetFillColor(op.Color) 110 | c.SetFont(p.font) 111 | c.SetFontSize(op.Size) 112 | c.FillStringAt(op.Text, op.X, op.Y) 113 | } 114 | -------------------------------------------------------------------------------- /arty/server/main.go: -------------------------------------------------------------------------------- 1 | package main 2 | 3 | import ( 4 | "image/color" 5 | "log" 6 | "net/http" 7 | "sync" 8 | 9 | "github.com/stdiopt/gowasm-experiments/arty/painter" 10 | 11 | "github.com/gorilla/websocket" 12 | ) 13 | 14 | func main() { 15 | addr := ":4444" 16 | log.Println("Listening at ", addr) 17 | server, err := NewCanvasServer(1920, 1080) 18 | if err != nil { 19 | log.Fatal("error starting canvas server", err) 20 | } 21 | http.ListenAndServe(addr, server) 22 | } 23 | 24 | type CanvasServer struct { 25 | painter *painter.BufPainter 26 | clients sync.Map 27 | } 28 | 29 | func NewCanvasServer(w, h int) (*CanvasServer, error) { 30 | p, err := painter.New() 31 | if err != nil { 32 | return nil, err 33 | } 34 | p.Init(painter.InitOP{Width: w, Height: h}) 35 | 36 | p.HandleOP(painter.TextOP{ 37 | Color: color.RGBA{R: 0, G: 0, B: 0, A: 255}, 38 | X: 10.0, 39 | Y: 10.0, 40 | Text: "Hello world", 41 | }) 42 | return &CanvasServer{p, sync.Map{}}, nil 43 | } 44 | 45 | var upgrader = websocket.Upgrader{ 46 | CheckOrigin: func(r *http.Request) bool { return true }, 47 | } 48 | 49 | func (s *CanvasServer) ServeHTTP(w http.ResponseWriter, r *http.Request) { 50 | log.Println("Receiving connection from:", r.RemoteAddr) 51 | c, err := upgrader.Upgrade(w, r, nil) 52 | if err != nil { 53 | log.Println("upgrade err", err) 54 | return 55 | } 56 | 57 | c.WriteJSON(painter.Message{painter.InitOP{ 58 | Width: s.painter.Width(), 59 | Height: s.painter.Height(), 60 | Data: s.painter.ImageData(), 61 | }}) 62 | if err != nil { 63 | log.Println("sending msg error") 64 | return 65 | } 66 | 67 | ncli := &Cli{conn: c} 68 | s.clients.Store(ncli, true) 69 | defer func() { 70 | c.Close() 71 | s.clients.Delete(ncli) 72 | }() 73 | for { 74 | mt, message, err := c.ReadMessage() 75 | if err != nil { 76 | log.Println("Bye bye", r.RemoteAddr) 77 | return 78 | } 79 | if mt != websocket.TextMessage { 80 | continue 81 | } 82 | // draw in server 83 | err = s.painter.HandleRaw(message) 84 | if err != nil { 85 | log.Println("what?", err) 86 | } 87 | 88 | // Broadcast to other clients 89 | s.clients.Range(func(key, value interface{}) bool { 90 | cl := key.(*Cli) 91 | if cl == ncli { 92 | return true 93 | } 94 | err := cl.send(mt, message) 95 | if err != nil { 96 | log.Println("Erro: sending to cli", err) 97 | } 98 | return true 99 | }) 100 | 101 | } 102 | } 103 | 104 | // Cli concurrent safe client 105 | type Cli struct { 106 | sync.Mutex 107 | conn *websocket.Conn 108 | } 109 | 110 | func (c *Cli) send(mt int, msg []byte) error { 111 | c.Lock() 112 | defer c.Unlock() 113 | return c.conn.WriteMessage(mt, msg) 114 | } 115 | -------------------------------------------------------------------------------- /bittune/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /bittune/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | go webassembly - bittune 5 | 15 | 16 | 22 | 23 | 24 | Using Web Audio API 25 |
26 |
27 | 28 | 29 | 30 | 31 | 32 |
33 | [source] 34 | 35 | 36 | -------------------------------------------------------------------------------- /bittune/main.go: -------------------------------------------------------------------------------- 1 | // +build js,wasm 2 | 3 | package main 4 | 5 | import ( 6 | "encoding/base64" 7 | "fmt" 8 | "math/rand" 9 | "strconv" 10 | "syscall/js" 11 | "time" 12 | ) 13 | 14 | func main() { 15 | t := &audioThing{} 16 | t.Start() 17 | } 18 | 19 | type dom struct { 20 | doc js.Value 21 | beat js.Value 22 | bpm js.Value 23 | bpmLbl js.Value 24 | tlen js.Value 25 | tlenLbl js.Value 26 | } 27 | 28 | type audioThing struct { 29 | ctx js.Value 30 | el dom 31 | 32 | ins []func() 33 | seq []bool 34 | curStep int 35 | 36 | BPM byte 37 | trackLen byte 38 | 39 | playing bool 40 | done chan struct{} 41 | 42 | wn js.Value 43 | } 44 | 45 | func (t *audioThing) Start() { 46 | 47 | t.done = make(chan struct{}, 0) 48 | 49 | doc := js.Global().Get("document") 50 | actx := js.Global().Get("AudioContext") 51 | if !actx.Truthy() { 52 | actx = js.Global().Get("webkitAudioContext") // safari 53 | } 54 | 55 | t.ctx = actx.New() 56 | 57 | t.el.beat = doc.Call("getElementById", "beat") 58 | t.el.bpm = doc.Call("getElementById", "bpm") 59 | t.el.bpmLbl = t.el.bpm.Get("nextElementSibling") 60 | t.el.tlen = doc.Call("getElementById", "tlen") 61 | t.el.tlenLbl = t.el.tlen.Get("nextElementSibling") 62 | 63 | notes := []float64{ 64 | 523.3, 554.4, 587.3, 622.3, 659.3, 698.5, 65 | 740.0, 784.0, 830.6, 880.0, 932.3, 987.8, 66 | } 67 | // Initialize instruments 68 | t.ins = []func(){ 69 | t.playKick, 70 | t.playSnare, 71 | t.playCHithat, 72 | } 73 | // Add tune 74 | for i := 0; i <= 12; i++ { 75 | n := notes[i%len(notes)] * (1 + float64((i / len(notes)))) 76 | t.ins = append(t.ins, t.createTune(n)) 77 | } 78 | bufSize := 4096 79 | t.wn = t.ctx.Call("createScriptProcessor", bufSize, 1, 1) 80 | whiteNoiseFn := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 81 | e := args[0] 82 | out := e.Get("outputBuffer").Call("getChannelData", 0) 83 | for i := 0; i < bufSize; i++ { 84 | out.SetIndex(i, rand.Float64()*2-1) 85 | } 86 | return nil 87 | }) 88 | defer whiteNoiseFn.Release() 89 | t.wn.Set("onaudioprocess", whiteNoiseFn) 90 | 91 | t.setBPM(80) 92 | t.setTrackLen(32) 93 | 94 | go t.handleEvents() 95 | t.hashRestore() 96 | 97 | <-t.done 98 | } 99 | 100 | func (t *audioThing) play() { 101 | if t.playing { 102 | return 103 | } 104 | t.playing = true 105 | 106 | go func() { 107 | for { 108 | beat := time.After(time.Minute / time.Duration(t.BPM) / 4) 109 | select { 110 | case <-t.done: 111 | return 112 | case <-beat: 113 | t.step() 114 | } 115 | } 116 | }() 117 | } 118 | 119 | // Build beats DOM 120 | func (t *audioThing) buildDOM() { 121 | beatHTML := "" 122 | for i := 0; i < len(t.seq)/len(t.ins); i++ { 123 | stepHTML := "" 124 | for j := 0; j < len(t.ins); j++ { 125 | stepHTML += fmt.Sprintf( 126 | `
`, 127 | i*len(t.ins)+j, 128 | ) 129 | } 130 | beatHTML += fmt.Sprintf(`
%s
`, stepHTML) 131 | } 132 | t.el.beat.Set("innerHTML", beatHTML) 133 | } 134 | 135 | func (t *audioThing) setTrackLen(n byte) { 136 | t.curStep = 0 137 | t.trackLen = n 138 | t.el.tlenLbl.Set("innerHTML", fmt.Sprint(n)) 139 | t.el.tlen.Set("value", fmt.Sprint(n)) 140 | 141 | t.seq = make([]bool, int(n)*len(t.ins)) 142 | t.buildDOM() 143 | } 144 | func (t *audioThing) setBPM(n byte) { 145 | t.BPM = n 146 | t.el.bpmLbl.Set("innerHTML", fmt.Sprintf("%d bpm", n)) 147 | t.el.bpm.Set("value", n) 148 | } 149 | 150 | // Set DOM events 151 | func (t *audioThing) handleEvents() { 152 | // Handle document click 153 | handleClick := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 154 | ev := args[0] 155 | target := ev.Get("target") 156 | if target.Call("matches", "#play").Bool() { 157 | t.play() 158 | target.Call("setAttribute", "disabled", "disabled") 159 | return nil 160 | } 161 | if !target.Call("matches", ".key").Bool() { 162 | return nil 163 | } 164 | keyIs := ev.Get("target").Call("getAttribute", "key").String() 165 | keyI, err := strconv.Atoi(keyIs) 166 | if err != nil { 167 | println("wrong key", keyIs) 168 | return nil 169 | } 170 | t.seq[keyI] = !t.seq[keyI] 171 | ev.Get("target").Get("classList").Call("toggle", "active", t.seq[keyI]) 172 | t.hashStore() 173 | return nil 174 | }) 175 | defer handleClick.Release() 176 | js.Global().Call("addEventListener", "click", handleClick) 177 | 178 | // handle location hashChange 179 | handleHashChange := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 180 | t.hashRestore() 181 | return nil 182 | }) 183 | defer handleHashChange.Release() 184 | js.Global().Call("addEventListener", "hashchange", handleHashChange) 185 | 186 | // handle bpm input 187 | handleBpmInput := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 188 | e := args[0] 189 | sval := e.Get("target").Get("value").String() 190 | bpm, err := strconv.Atoi(sval) 191 | if err != nil { 192 | println("wrong input value") 193 | return nil 194 | } 195 | 196 | t.setBPM(byte(bpm)) 197 | t.hashStore() 198 | return nil 199 | }) 200 | defer handleBpmInput.Release() 201 | t.el.bpm.Call("addEventListener", "input", handleBpmInput) 202 | 203 | // handle track length input 204 | handleTrackLenInput := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 205 | e := args[0] 206 | sval := e.Get("target").Get("value").String() 207 | tlen, err := strconv.Atoi(sval) 208 | if err != nil { 209 | println("wrong input value") 210 | return nil 211 | } 212 | t.setTrackLen(byte(tlen)) 213 | t.hashStore() 214 | return nil 215 | }) 216 | defer handleTrackLenInput.Release() 217 | t.el.tlen.Call("addEventListener", "input", handleTrackLenInput) 218 | 219 | <-t.done 220 | } 221 | 222 | func (t *audioThing) step() { 223 | t.el.beat. 224 | Get("children"). 225 | Index(t.curStep). 226 | Get("classList"). 227 | Call("toggle", "current", false) 228 | t.curStep = (t.curStep + 1) % int(t.trackLen) 229 | t.el.beat. 230 | Get("children"). 231 | Index(t.curStep). 232 | Get("classList"). 233 | Call("toggle", "current", true) 234 | for i := range t.ins { 235 | if t.seq[t.curStep*len(t.ins)+i] { 236 | t.ins[i]() 237 | } 238 | } 239 | } 240 | 241 | func (t *audioThing) hashStore() { 242 | var bitbuf = make([]byte, len(t.seq)/8+3) 243 | bitbuf[0] = t.BPM 244 | bitbuf[1] = t.trackLen 245 | bcur := 1 246 | for i := range t.seq { 247 | if i&7 == 0 { 248 | bcur++ 249 | } 250 | v := 0 251 | if t.seq[i] { 252 | v = 1 253 | } 254 | bitbuf[bcur] |= byte(v << uint(7-(i&7))) 255 | } 256 | b64 := base64.StdEncoding.EncodeToString(bitbuf) 257 | js.Global().Get("history").Call("pushState", b64, "", "#"+b64) 258 | } 259 | 260 | func (t *audioThing) hashRestore() { 261 | hash := js.Global().Get("location").Get("hash").String() 262 | if len(hash) == 0 { 263 | return 264 | } 265 | hash = hash[1:] // skip '#' 266 | bitbuf, err := base64.StdEncoding.DecodeString(hash) 267 | if err != nil { 268 | fmt.Println("wrong hash", err) 269 | return 270 | } 271 | t.setBPM(bitbuf[0]) 272 | if bitbuf[1] != t.trackLen { 273 | t.setTrackLen(bitbuf[1]) 274 | } 275 | bitbuf = bitbuf[2:] 276 | steps := []bool{} 277 | 278 | doc := js.Global().Get("document") 279 | for i := 0; i < len(bitbuf); i++ { 280 | for j := 7; j >= 0; j-- { 281 | v := ((bitbuf[i] >> uint(j)) & 1) != 0 282 | steps = append(steps, v) 283 | el := doc.Call("querySelector", 284 | fmt.Sprintf(`[key="%d"]`, len(steps)-1), 285 | ) 286 | if !el.Truthy() { 287 | continue 288 | } 289 | el.Get("classList").Call("toggle", "active", v) 290 | } 291 | } 292 | t.seq = steps 293 | } 294 | 295 | // Improve this 296 | func (t *audioThing) playKick() { 297 | currentTime := t.ctx.Get("currentTime").Float() 298 | 299 | g := t.ctx.Call("createGain") 300 | g.Call("connect", t.ctx.Get("destination")) 301 | g.Get("gain").Set("value", 0.4) 302 | g.Get("gain").Call("linearRampToValueAtTime", 0, currentTime+0.05) 303 | 304 | f := t.ctx.Call("createBiquadFilter") 305 | f.Call("connect", g) 306 | f.Set("type", "lowpass") 307 | f.Get("frequency").Set("value", 400) 308 | f.Get("frequency").Call("linearRampToValueAtTime", 1, currentTime+0.1) 309 | 310 | o := t.ctx.Call("createOscillator") 311 | o.Call("connect", g) 312 | o.Set("type", "sine") 313 | o.Get("frequency").Set("value", 40) 314 | 315 | var ended js.Func 316 | ended = js.FuncOf(func(t js.Value, args []js.Value) interface{} { 317 | g.Call("disconnect") 318 | ended.Release() 319 | return nil 320 | }) 321 | o.Set("onended", ended) 322 | o.Call("start") 323 | o.Call("stop", currentTime+0.05) 324 | } 325 | 326 | func (t *audioThing) playSnare() { 327 | currentTime := t.ctx.Get("currentTime").Float() 328 | 329 | g := t.ctx.Call("createGain") 330 | g.Call("connect", t.ctx.Get("destination")) 331 | g.Get("gain").Set("value", 0.3) 332 | g.Get("gain").Call("linearRampToValueAtTime", 0, currentTime+0.1) 333 | 334 | f := t.ctx.Call("createBiquadFilter") 335 | f.Call("connect", g) 336 | f.Set("type", "bandpass") 337 | f.Get("frequency").Set("value", 500) 338 | f.Get("frequency").Call("linearRampToValueAtTime", 1500, currentTime+0.02) 339 | 340 | o := t.ctx.Call("createOscillator") 341 | o.Call("connect", f) 342 | o.Set("type", "sine") 343 | o.Get("frequency").Set("value", 220) 344 | o.Get("frequency").Call("linearRampToValueAtTime", 10, currentTime+0.1) 345 | 346 | var ended js.Func 347 | ended = js.FuncOf(func(t js.Value, args []js.Value) interface{} { 348 | g.Call("disconnect") 349 | ended.Release() 350 | return nil 351 | }) 352 | o.Set("onended", ended) 353 | o.Call("start") 354 | o.Call("stop", currentTime+0.1) 355 | 356 | g2 := t.ctx.Call("createGain") 357 | g2.Call("connect", f) 358 | g2.Get("gain").Set("value", 0.1) 359 | g2.Get("gain").Call("linearRampToValueAtTime", 0.2, currentTime+0.001) 360 | 361 | t.wn.Call("connect", g2) 362 | 363 | } 364 | 365 | func (t *audioThing) playCHithat() { 366 | currentTime := t.ctx.Get("currentTime").Float() 367 | g := t.ctx.Call("createGain") 368 | g.Call("connect", t.ctx.Get("destination")) 369 | g.Get("gain").Set("value", 0.01) 370 | g.Get("gain").Call("linearRampToValueAtTime", 0, currentTime+0.02) 371 | 372 | f := t.ctx.Call("createBiquadFilter") 373 | f.Call("connect", g) 374 | f.Set("type", "highpass") 375 | f.Get("frequency").Set("value", 5000) 376 | 377 | o := t.ctx.Call("createOscillator") 378 | o.Call("connect", f) 379 | var ended js.Func 380 | ended = js.FuncOf(func(t js.Value, args []js.Value) interface{} { 381 | g.Call("disconnect") 382 | ended.Release() 383 | return nil 384 | }) 385 | o.Set("onended", ended) 386 | o.Call("start") 387 | o.Call("stop", currentTime+0.1) 388 | t.wn.Call("connect", f) 389 | 390 | } 391 | 392 | func (t *audioThing) createTune(freq float64) func() { 393 | return func() { 394 | currentTime := t.ctx.Get("currentTime").Float() 395 | g := t.ctx.Call("createGain") 396 | g.Call("connect", t.ctx.Get("destination")) 397 | g.Get("gain").Set("value", 0.03) 398 | g.Get("gain").Call("exponentialRampToValueAtTime", 0.0001, currentTime+2) 399 | 400 | o := t.ctx.Call("createOscillator") 401 | o.Set("type", "sine") 402 | o.Get("frequency").Call("linearRampToValueAtTime", freq, currentTime+0.02) 403 | o.Call("connect", g) 404 | 405 | var ended js.Func 406 | ended = js.FuncOf(func(t js.Value, args []js.Value) interface{} { 407 | g.Call("disconnect") 408 | ended.Release() 409 | return nil 410 | }) 411 | o.Set("onended", ended) 412 | o.Call("start") 413 | o.Call("stop", currentTime+2) 414 | } 415 | } 416 | -------------------------------------------------------------------------------- /bittune/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/bittune/main.wasm -------------------------------------------------------------------------------- /bittune/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | -------------------------------------------------------------------------------- /bouncy/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /bouncy/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - bouncy 4 | 5 | 6 | 7 | 8 | 35 | 60 | 61 | 62 |
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84 | 85 | 86 | -------------------------------------------------------------------------------- /bouncy/main.go: -------------------------------------------------------------------------------- 1 | //Wasming 2 | // compile: GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 3 | package main 4 | 5 | import ( 6 | "fmt" 7 | "math" 8 | "math/rand" 9 | "strconv" 10 | "syscall/js" 11 | ) 12 | 13 | var ( 14 | width float64 15 | height float64 16 | mousePos [2]float64 17 | ctx js.Value 18 | lineDistSq float64 = 100 * 100 19 | ) 20 | 21 | func main() { 22 | 23 | // Init Canvas stuff 24 | doc := js.Global().Get("document") 25 | canvasEl := doc.Call("getElementById", "mycanvas") 26 | width = doc.Get("body").Get("clientWidth").Float() 27 | height = doc.Get("body").Get("clientHeight").Float() 28 | canvasEl.Set("width", width) 29 | canvasEl.Set("height", height) 30 | ctx = canvasEl.Call("getContext", "2d") 31 | 32 | done := make(chan struct{}, 0) 33 | 34 | dt := DotThing{speed: 160, size: 6} 35 | 36 | mouseMoveEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 37 | e := args[0] 38 | mousePos[0] = e.Get("clientX").Float() 39 | mousePos[1] = e.Get("clientY").Float() 40 | return nil 41 | }) 42 | defer mouseMoveEvt.Release() 43 | 44 | // Event handler for count range 45 | countChangeEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 46 | evt := args[0] 47 | intVal, err := strconv.Atoi(evt.Get("target").Get("value").String()) 48 | if err != nil { 49 | println("Invalid value", err) 50 | return nil 51 | } 52 | dt.SetNDots(intVal) 53 | return nil 54 | }) 55 | defer countChangeEvt.Release() 56 | 57 | // Event handler for speed range 58 | speedInputEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 59 | evt := args[0] 60 | fval, err := strconv.ParseFloat(evt.Get("target").Get("value").String(), 64) 61 | if err != nil { 62 | println("invalid value", err) 63 | return nil 64 | } 65 | dt.speed = fval 66 | return nil 67 | }) 68 | defer speedInputEvt.Release() 69 | 70 | // Event handler for size 71 | sizeChangeEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 72 | evt := args[0] 73 | intVal, err := strconv.Atoi(evt.Get("target").Get("value").String()) 74 | if err != nil { 75 | println("invalid value", err) 76 | return nil 77 | } 78 | dt.size = intVal 79 | return nil 80 | }) 81 | defer sizeChangeEvt.Release() 82 | 83 | // Event handler for lines toggle 84 | lineChangeEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 85 | evt := args[0] 86 | dt.lines = evt.Get("target").Get("checked").Bool() 87 | return nil 88 | }) 89 | defer lineChangeEvt.Release() 90 | 91 | // Event handler for dashed toggle 92 | dashedChangeEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 93 | evt := args[0] 94 | dt.dashed = evt.Get("target").Get("checked").Bool() 95 | return nil 96 | }) 97 | defer dashedChangeEvt.Release() 98 | 99 | doc.Call("addEventListener", "mousemove", mouseMoveEvt) 100 | doc.Call("getElementById", "count").Call("addEventListener", "change", countChangeEvt) 101 | doc.Call("getElementById", "speed").Call("addEventListener", "input", speedInputEvt) 102 | doc.Call("getElementById", "size").Call("addEventListener", "input", sizeChangeEvt) 103 | doc.Call("getElementById", "dashed").Call("addEventListener", "change", dashedChangeEvt) 104 | doc.Call("getElementById", "lines").Call("addEventListener", "change", lineChangeEvt) 105 | 106 | dt.SetNDots(100) 107 | dt.lines = false 108 | var renderFrame js.Func 109 | var tmark float64 110 | var markCount = 0 111 | var tdiffSum float64 112 | 113 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 114 | now := args[0].Float() 115 | tdiff := now - tmark 116 | tdiffSum += now - tmark 117 | markCount++ 118 | if markCount > 10 { 119 | doc.Call("getElementById", "fps").Set("innerHTML", fmt.Sprintf("FPS: %.01f", 1000/(tdiffSum/float64(markCount)))) 120 | tdiffSum, markCount = 0, 0 121 | } 122 | tmark = now 123 | 124 | // Pull window size to handle resize 125 | curBodyW := doc.Get("body").Get("clientWidth").Float() 126 | curBodyH := doc.Get("body").Get("clientHeight").Float() 127 | if curBodyW != width || curBodyH != height { 128 | width, height = curBodyW, curBodyH 129 | canvasEl.Set("width", width) 130 | canvasEl.Set("height", height) 131 | } 132 | dt.Update(tdiff / 1000) 133 | 134 | js.Global().Call("requestAnimationFrame", renderFrame) 135 | return nil 136 | }) 137 | defer renderFrame.Release() 138 | 139 | // Start running 140 | js.Global().Call("requestAnimationFrame", renderFrame) 141 | 142 | <-done 143 | 144 | } 145 | 146 | // DotThing manager 147 | type DotThing struct { 148 | dots []*Dot 149 | dashed bool 150 | lines bool 151 | speed float64 152 | size int 153 | } 154 | 155 | // Update updates the dot positions and draws 156 | func (dt *DotThing) Update(dtTime float64) { 157 | if dt.dots == nil { 158 | return 159 | } 160 | ctx.Call("clearRect", 0, 0, width, height) 161 | 162 | // Update 163 | for i, dot := range dt.dots { 164 | dir := [2]float64{} 165 | // Bounce 166 | if dot.pos[0] < 0 { 167 | dot.pos[0] = 0 168 | dot.dir[0] *= -1 169 | } 170 | if dot.pos[0] > width { 171 | dot.pos[0] = width 172 | dot.dir[0] *= -1 173 | } 174 | 175 | if dot.pos[1] < 0 { 176 | dot.pos[1] = 0 177 | dot.dir[1] *= -1 178 | } 179 | 180 | if dot.pos[1] > height { 181 | dot.pos[1] = height 182 | dot.dir[1] *= -1 183 | } 184 | dir = dot.dir 185 | 186 | ctx.Set("globalAlpha", 0.5) 187 | ctx.Call("beginPath") 188 | ctx.Set("fillStyle", fmt.Sprintf("#%06x", dot.color)) 189 | ctx.Set("strokeStyle", fmt.Sprintf("#%06x", dot.color)) 190 | // Dashed array ref: https://github.com/golang/go/blob/release-branch.go1.11/src/syscall/js/js.go#L98 191 | ctx.Call("setLineDash", []interface{}{}) 192 | if dt.dashed { 193 | ctx.Call("setLineDash", []interface{}{5, 10}) 194 | } 195 | ctx.Set("lineWidth", dt.size) 196 | ctx.Call("arc", dot.pos[0], dot.pos[1], dt.size, 0, 2*math.Pi) 197 | ctx.Call("fill") 198 | 199 | mdx := mousePos[0] - dot.pos[0] 200 | mdy := mousePos[1] - dot.pos[1] 201 | d := math.Sqrt(mdx*mdx + mdy*mdy) 202 | if d < 200 { 203 | ctx.Set("globalAlpha", 1-d/200) 204 | ctx.Call("beginPath") 205 | ctx.Call("moveTo", dot.pos[0], dot.pos[1]) 206 | ctx.Call("lineTo", mousePos[0], mousePos[1]) 207 | ctx.Call("stroke") 208 | if d > 100 { // move towards mouse 209 | dir[0] = (mdx / d) * 2 210 | dir[1] = (mdy / d) * 2 211 | } else { // do not move 212 | dir[0] = 0 213 | dir[1] = 0 214 | } 215 | } 216 | 217 | if dt.lines { 218 | for _, dot2 := range dt.dots[i+1:] { 219 | mx := dot2.pos[0] - dot.pos[0] 220 | my := dot2.pos[1] - dot.pos[1] 221 | d := mx*mx + my*my 222 | if d < lineDistSq { 223 | ctx.Set("globalAlpha", 1-d/lineDistSq) 224 | ctx.Call("beginPath") 225 | ctx.Call("moveTo", dot.pos[0], dot.pos[1]) 226 | ctx.Call("lineTo", dot2.pos[0], dot2.pos[1]) 227 | ctx.Call("stroke") 228 | } 229 | } 230 | } 231 | 232 | dot.pos[0] += dir[0] * dt.speed * dtTime 233 | dot.pos[1] += dir[1] * dt.speed * dtTime 234 | } 235 | } 236 | 237 | // SetNDots reinitializes dots with n size 238 | func (dt *DotThing) SetNDots(n int) { 239 | dt.dots = make([]*Dot, n) 240 | for i := 0; i < n; i++ { 241 | dt.dots[i] = &Dot{ 242 | pos: [2]float64{ 243 | rand.Float64() * width, 244 | rand.Float64() * height, 245 | }, 246 | dir: [2]float64{ 247 | rand.NormFloat64(), 248 | rand.NormFloat64(), 249 | }, 250 | color: uint32(rand.Intn(0xFFFFFF)), 251 | size: 10, 252 | } 253 | } 254 | } 255 | 256 | // Dot represents a dot ... 257 | type Dot struct { 258 | pos [2]float64 259 | dir [2]float64 260 | color uint32 261 | size float64 262 | } 263 | -------------------------------------------------------------------------------- /bouncy/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/bouncy/main.wasm -------------------------------------------------------------------------------- /bouncy/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | -------------------------------------------------------------------------------- /bumpy/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /bumpy/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - bumpy 4 | 5 | 6 | 7 | 8 | 33 | 58 | 59 | 60 |
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69 |
70 | 71 | 72 | -------------------------------------------------------------------------------- /bumpy/main.go: -------------------------------------------------------------------------------- 1 | // Click on canvas to start a polygon 2 | // - Max 8 vertices 3 | // - Only convex polygons 4 | // - Esc cancel polygon 5 | 6 | //Wasming 7 | // compile: GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 8 | package main 9 | 10 | import ( 11 | "fmt" 12 | "math" 13 | "math/rand" 14 | "strconv" 15 | "syscall/js" 16 | 17 | // this box2d throws some unexpected panics 18 | "github.com/ByteArena/box2d" 19 | ) 20 | 21 | var ( 22 | width float64 23 | height float64 24 | ctx js.Value 25 | simSpeed float64 = 1 26 | worldScale float64 = 0.0125 // 1/8 27 | ) 28 | 29 | func main() { 30 | 31 | // Init Canvas stuff 32 | doc := js.Global().Get("document") 33 | canvasEl := doc.Call("getElementById", "mycanvas") 34 | width = doc.Get("body").Get("clientWidth").Float() 35 | height = doc.Get("body").Get("clientHeight").Float() 36 | canvasEl.Call("setAttribute", "width", width) 37 | canvasEl.Call("setAttribute", "height", height) 38 | ctx = canvasEl.Call("getContext", "2d") 39 | ctx.Call("scale", 1/worldScale, 1/worldScale) 40 | 41 | done := make(chan struct{}, 0) 42 | 43 | world := box2d.MakeB2World(box2d.B2Vec2{X: 0, Y: 9.8}) 44 | var verts []box2d.B2Vec2 45 | 46 | keyUpEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 47 | e := args[0] 48 | if e.Get("which").Int() == 27 { 49 | verts = nil 50 | } 51 | return nil 52 | }) 53 | defer keyUpEvt.Release() 54 | mouseDownEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 55 | defer func() { 56 | // Recovering from possible box2d panic 57 | if r := recover(); r != nil { 58 | verts = nil 59 | } 60 | }() 61 | 62 | e := args[0] 63 | if e.Get("target") != canvasEl { 64 | return nil 65 | } 66 | mx := e.Get("clientX").Float() * worldScale 67 | my := e.Get("clientY").Float() * worldScale 68 | // Start shape 69 | if verts == nil { 70 | verts = []box2d.B2Vec2{box2d.B2Vec2{mx, my}} 71 | return nil 72 | } 73 | dx := mx - verts[0].X 74 | dy := my - verts[0].Y 75 | d := math.Sqrt(dx*dx + dy*dy) 76 | /////// 77 | // if clicked on the single spot we create a ball 78 | if len(verts) == 1 && d < 10*worldScale { 79 | obj1 := world.CreateBody(&box2d.B2BodyDef{ 80 | Type: box2d.B2BodyType.B2_dynamicBody, 81 | Position: box2d.B2Vec2{X: mx, Y: my}, 82 | Awake: true, 83 | Active: true, 84 | GravityScale: 1.0, 85 | }) 86 | shape := box2d.NewB2CircleShape() 87 | shape.M_radius = (10 + rand.Float64()*10) * worldScale 88 | ft := obj1.CreateFixture(shape, 1) 89 | ft.M_friction = 0.3 90 | ft.M_restitution = 0.7 91 | verts = nil 92 | return nil 93 | } 94 | if len(verts) > 2 && d < 10*worldScale || len(verts) == 8 { 95 | 96 | // Seems box2d panics when we create a polygon counterclockwise most 97 | // likely due to normals and centroids calculations so basically we 98 | // recover from that panic and invert the polygon and try again 99 | var center *box2d.B2Vec2 100 | func() { 101 | defer func() { recover() }() 102 | lc := box2d.ComputeCentroid(verts, len(verts)) 103 | center = &lc 104 | }() 105 | if center == nil { 106 | //vert inversion 107 | verts2 := make([]box2d.B2Vec2, len(verts)) 108 | for i := range verts { 109 | verts2[len(verts)-1-i] = verts[i] 110 | } 111 | verts = verts2 112 | // Retry 113 | lc := box2d.ComputeCentroid(verts, len(verts)) 114 | center = &lc 115 | } 116 | 117 | // translate -center 118 | for i := range verts { 119 | verts[i].X -= center.X 120 | verts[i].Y -= center.Y 121 | } 122 | shape := box2d.NewB2PolygonShape() 123 | shape.Set(verts, len(verts)) 124 | 125 | obj := world.CreateBody(&box2d.B2BodyDef{ 126 | Type: box2d.B2BodyType.B2_dynamicBody, 127 | Position: *center, 128 | Awake: true, 129 | Active: true, 130 | GravityScale: 1.0, 131 | }) 132 | fixture := obj.CreateFixture(shape, 10) 133 | fixture.M_friction = 0.3 134 | verts = nil 135 | return nil 136 | } 137 | verts = append(verts, box2d.B2Vec2{mx, my}) 138 | return nil 139 | }) 140 | defer mouseDownEvt.Release() 141 | 142 | speedInputEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 143 | evt := args[0] 144 | fval, err := strconv.ParseFloat(evt.Get("target").Get("value").String(), 64) 145 | if err != nil { 146 | println("Invalid value", err) 147 | return nil 148 | } 149 | simSpeed = fval 150 | return nil 151 | }) 152 | defer speedInputEvt.Release() 153 | 154 | doc.Call("addEventListener", "keyup", keyUpEvt) 155 | doc.Call("addEventListener", "mousedown", mouseDownEvt) 156 | doc.Call("getElementById", "speed").Call("addEventListener", "input", speedInputEvt) 157 | 158 | // Floor 159 | floor := world.CreateBody(&box2d.B2BodyDef{ 160 | Type: box2d.B2BodyType.B2_kinematicBody, 161 | Position: box2d.B2Vec2{X: 0, Y: height*worldScale - 20*worldScale}, 162 | Active: true, 163 | }) 164 | floorShape := &box2d.B2PolygonShape{} 165 | floorShape.SetAsBox(width*worldScale, 20*worldScale) 166 | ft := floor.CreateFixture(floorShape, 1) 167 | ft.M_friction = 0.3 168 | 169 | // Some Random falling balls 170 | for i := 0; i < 10; i++ { 171 | obj1 := world.CreateBody(&box2d.B2BodyDef{ 172 | Type: box2d.B2BodyType.B2_dynamicBody, 173 | Position: box2d.B2Vec2{X: rand.Float64() * width * worldScale, Y: rand.Float64() * height * worldScale}, 174 | Awake: true, 175 | Active: true, 176 | GravityScale: 1.0, 177 | }) 178 | shape := box2d.NewB2CircleShape() 179 | shape.M_radius = 10 * worldScale 180 | ft := obj1.CreateFixture(shape, 1) 181 | ft.M_friction = 0.3 182 | ft.M_restitution = 0.5 // bouncy 183 | } 184 | 185 | // Draw things 186 | var renderFrame js.Func 187 | var tmark float64 188 | 189 | // overall style 190 | ctx.Set("fillStyle", "rgba(100,150,100,0.4)") 191 | ctx.Set("strokeStyle", "rgba(100,150,100,1)") 192 | ctx.Set("lineWidth", 2*worldScale) 193 | 194 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 195 | now := args[0].Float() 196 | tdiff := now - tmark 197 | doc.Call("getElementById", "fps").Set("innerHTML", fmt.Sprintf("FPS: %.01f", 1000/tdiff)) 198 | tmark = now 199 | 200 | // Pool window size to handle resize 201 | curBodyW := doc.Get("body").Get("clientWidth").Float() 202 | curBodyH := doc.Get("body").Get("clientHeight").Float() 203 | if curBodyW != width || curBodyH != height { 204 | width, height = curBodyW, curBodyH 205 | canvasEl.Set("width", width) 206 | canvasEl.Set("height", height) 207 | } 208 | world.Step(tdiff/1000*simSpeed, 60, 120) 209 | 210 | ctx.Call("clearRect", 0, 0, width*worldScale, height*worldScale) 211 | 212 | for curBody := world.GetBodyList(); curBody != nil; curBody = curBody.M_next { 213 | // Only one fixture for now 214 | ctx.Call("save") 215 | ft := curBody.M_fixtureList 216 | switch shape := ft.M_shape.(type) { 217 | case *box2d.B2PolygonShape: // Box 218 | // canvas translate 219 | ctx.Call("translate", curBody.M_xf.P.X, curBody.M_xf.P.Y) 220 | ctx.Call("rotate", curBody.M_xf.Q.GetAngle()) 221 | ctx.Call("beginPath") 222 | ctx.Call("moveTo", shape.M_vertices[0].X, shape.M_vertices[0].Y) 223 | for _, v := range shape.M_vertices[1:shape.M_count] { 224 | ctx.Call("lineTo", v.X, v.Y) 225 | } 226 | ctx.Call("lineTo", shape.M_vertices[0].X, shape.M_vertices[0].Y) 227 | ctx.Call("fill") 228 | ctx.Call("stroke") 229 | case *box2d.B2CircleShape: 230 | ctx.Call("translate", curBody.M_xf.P.X, curBody.M_xf.P.Y) 231 | ctx.Call("rotate", curBody.M_xf.Q.GetAngle()) 232 | ctx.Call("beginPath") 233 | ctx.Call("arc", 0, 0, shape.M_radius, 0, 2*math.Pi) 234 | ctx.Call("fill") 235 | ctx.Call("moveTo", 0, 0) 236 | ctx.Call("lineTo", 0, shape.M_radius) 237 | ctx.Call("stroke") 238 | } 239 | ctx.Call("restore") 240 | 241 | } 242 | // If we have a verts (mouse shape) 243 | if verts != nil { 244 | ctx.Call("save") 245 | ctx.Call("beginPath") 246 | ctx.Call("moveTo", verts[0].X, verts[0].Y) 247 | for _, v := range verts[1:] { 248 | ctx.Call("lineTo", v.X, v.Y) 249 | } 250 | ctx.Call("stroke") 251 | 252 | ctx.Set("lineWidth", 4*worldScale) 253 | for _, v := range verts { // Draw the clickPoints 254 | ctx.Call("beginPath") 255 | ctx.Call("arc", v.X, v.Y, 5*worldScale, 0, math.Pi*2) 256 | ctx.Call("stroke") 257 | } 258 | ctx.Call("restore") 259 | } 260 | js.Global().Call("requestAnimationFrame", renderFrame) 261 | return nil 262 | }) 263 | 264 | // Start running 265 | js.Global().Call("requestAnimationFrame", renderFrame) 266 | 267 | <-done 268 | 269 | } 270 | -------------------------------------------------------------------------------- /bumpy/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/bumpy/main.wasm -------------------------------------------------------------------------------- /bumpy/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | -------------------------------------------------------------------------------- /go.mod: -------------------------------------------------------------------------------- 1 | module github.com/stdiopt/gowasm-experiments 2 | 3 | go 1.13 4 | 5 | require ( 6 | github.com/ByteArena/box2d v1.0.2 7 | github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 8 | github.com/gorilla/websocket v1.4.0 9 | github.com/llgcode/draw2d v0.0.0-20180825133448-f52c8a71aff0 10 | github.com/lucasb-eyer/go-colorful v1.0.2 11 | github.com/pmezard/go-difflib v1.0.0 // indirect 12 | ) 13 | -------------------------------------------------------------------------------- /go.sum: -------------------------------------------------------------------------------- 1 | github.com/ByteArena/box2d v1.0.2 h1:f7f9KEQWhCs1n516DMLzi5w6u0MeeE78Mes4fWMcj9k= 2 | github.com/ByteArena/box2d v1.0.2/go.mod h1:LzEuxY9iCz+tskfWCY3o0ywYBRafDDugdSj+/YGI6sE= 3 | github.com/DATA-DOG/go-sqlmock v1.3.3 h1:CWUqKXe0s8A2z6qCgkP4Kru7wC11YoAnoupUKFDnH08= 4 | github.com/DATA-DOG/go-sqlmock v1.3.3/go.mod h1:f/Ixk793poVmq4qj/V1dPUg2JEAKC73Q5eFN3EC/SaM= 5 | github.com/go-gl/gl v0.0.0-20180407155706-68e253793080/go.mod h1:482civXOzJJCPzJ4ZOX/pwvXBWSnzD4OKMdH4ClKGbk= 6 | github.com/go-gl/glfw v0.0.0-20180426074136-46a8d530c326/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU= 7 | github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g= 8 | github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k= 9 | github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q= 10 | github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ= 11 | github.com/jung-kurt/gofpdf v1.0.0/go.mod h1:7Id9E/uU8ce6rXgefFLlgrJj/GYY22cpxn+r32jIOes= 12 | github.com/llgcode/draw2d v0.0.0-20180825133448-f52c8a71aff0 h1:2vp6ESimuT8pCuZHThVyV0hlfa9oPL06HnGCL9pbUgc= 13 | github.com/llgcode/draw2d v0.0.0-20180825133448-f52c8a71aff0/go.mod h1:mVa0dA29Db2S4LVqDYLlsePDzRJLDfdhVZiI15uY0FA= 14 | github.com/llgcode/ps v0.0.0-20150911083025-f1443b32eedb h1:61ndUreYSlWFeCY44JxDDkngVoI7/1MVhEl98Nm0KOk= 15 | github.com/llgcode/ps v0.0.0-20150911083025-f1443b32eedb/go.mod h1:1l8ky+Ew27CMX29uG+a2hNOKpeNYEQjjtiALiBlFQbY= 16 | github.com/lucasb-eyer/go-colorful v1.0.2 h1:mCMFu6PgSozg9tDNMMK3g18oJBX7oYGrC09mS6CXfO4= 17 | github.com/lucasb-eyer/go-colorful v1.0.2/go.mod h1:0MS4r+7BZKSJ5mw4/S5MPN+qHFF1fYclkSPilDOKW0s= 18 | github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM= 19 | github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4= 20 | golang.org/x/image v0.0.0-20180708004352-c73c2afc3b81 h1:00VmoueYNlNz/aHIilyyQz/MHSqGoWJzpFv/HW8xpzI= 21 | golang.org/x/image v0.0.0-20180708004352-c73c2afc3b81/go.mod h1:ux5Hcp/YLpHSI86hEcLt0YII63i6oz57MZXIpbrjZUs= 22 | -------------------------------------------------------------------------------- /hexy/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /hexy/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - what the hex 4 | 5 | 6 | 7 | 8 | 35 | 60 | 61 | 62 |
63 |
64 |
65 | 66 |
67 |
0
68 | 85 |
86 | 87 | 88 | -------------------------------------------------------------------------------- /hexy/main.go: -------------------------------------------------------------------------------- 1 | // +build js 2 | 3 | package main 4 | 5 | import ( 6 | "fmt" 7 | "math" 8 | "math/rand" 9 | "syscall/js" 10 | ) 11 | 12 | const ( 13 | nPoints = 20 14 | hexE = 30 15 | speed = 2.5 16 | deg2rad = 0.017453292 // pi/180 17 | ) 18 | 19 | var ( 20 | hexH = math.Sqrt(3) * hexE 21 | hexD = float64(math.Round(3 * hexE)) 22 | ) 23 | 24 | func main() { 25 | ht := hexThing{} 26 | ht.SetNDots(nPoints) 27 | ht.start() 28 | 29 | } 30 | 31 | type hexThing struct { 32 | dots []*dot 33 | 34 | doc js.Value 35 | ctx js.Value 36 | 37 | backCtx []js.Value 38 | curCtx int 39 | 40 | width float64 41 | height float64 42 | fcount int 43 | 44 | // callbacks 45 | } 46 | 47 | func (ht *hexThing) start() { 48 | ht.doc = js.Global().Get("document") 49 | canvasEl := ht.doc.Call("getElementById", "mycanvas") 50 | ht.ctx = canvasEl.Call("getContext", "2d") 51 | 52 | // Create 2 backbuffers 53 | for i := 0; i < 2; i++ { 54 | cv := ht.doc.Call("createElement", "canvas") 55 | cv.Set("width", ht.width) 56 | cv.Set("height", ht.height) 57 | ctx := cv.Call("getContext", "2d") 58 | ht.backCtx = append(ht.backCtx, ctx) 59 | } 60 | 61 | var renderFrame js.Func 62 | var tmark float64 63 | var markCount = 0 64 | var tdiffSum float64 65 | 66 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 67 | // FPS thing 68 | now := args[0].Float() 69 | tdiff := now - tmark 70 | tdiffSum += now - tmark 71 | markCount++ 72 | if markCount > 10 { 73 | ht.doc.Call("getElementById", "fps").Set("innerHTML", fmt.Sprintf("FPS: %.01f", 1000/(tdiffSum/float64(markCount)))) 74 | tdiffSum, markCount = 0, 0 75 | } 76 | tmark = now 77 | 78 | // Canvas size handler 79 | curBodyW := ht.doc.Get("body").Get("clientWidth").Float() / 2 80 | curBodyH := ht.doc.Get("body").Get("clientHeight").Float() / 2 81 | if curBodyW != ht.width || curBodyH != ht.height { 82 | ht.width, ht.height = curBodyW, curBodyH 83 | canvasEl.Set("width", ht.width) 84 | canvasEl.Set("height", ht.height) 85 | // update back buffers too 86 | for _, cx := range ht.backCtx { 87 | cv := cx.Get("canvas") 88 | cv.Set("width", ht.width) 89 | cv.Set("height", ht.height) 90 | } 91 | } 92 | 93 | ht.Update(tdiff / 1000) 94 | 95 | js.Global().Call("requestAnimationFrame", renderFrame) 96 | return nil 97 | }) 98 | 99 | done := make(chan struct{}, 0) 100 | 101 | js.Global().Call("requestAnimationFrame", renderFrame) 102 | <-done 103 | } 104 | 105 | func (ht *hexThing) Update(dtTime float64) { 106 | ht.fcount++ 107 | prevCtx := ht.backCtx[ht.curCtx] 108 | ht.curCtx = (ht.curCtx + 1) % len(ht.backCtx) 109 | ctx := ht.backCtx[ht.curCtx] 110 | 111 | ctx.Call("clearRect", 0, 0, ht.width, ht.height) 112 | ctx.Set("globalAlpha", 1) 113 | filter := "hue-rotate(3deg) grayscale(1%)" 114 | if ht.fcount%120 == 0 { 115 | filter += " opacity(0.98)" 116 | } 117 | if ht.fcount%8 == 0 { 118 | filter += " blur(1px)" 119 | } 120 | ctx.Set("filter", filter) 121 | ctx.Call("drawImage", prevCtx.Get("canvas"), 0, 0) 122 | ctx.Set("filter", "") 123 | 124 | for _, d := range ht.dots { 125 | d.life -= 0.005 126 | if d.life < 0 { // Reset 127 | ht.dotReset(d) 128 | continue 129 | } 130 | d.r += speed 131 | if d.r >= hexE { 132 | sign := 1.0 133 | if rand.Float64()-0.5 < 0 { 134 | sign = -1.0 135 | } 136 | d.dir += 60 * sign 137 | d.r = 0 138 | } 139 | 140 | prevPos := d.pos 141 | 142 | d.x += math.Cos(d.dir*deg2rad) * speed 143 | d.y += math.Sin(d.dir*deg2rad) * speed 144 | // out of bounds 145 | if d.x < 0 || d.x > ht.width || d.y < 0 || d.y > ht.height { 146 | ht.dotReset(d) 147 | continue 148 | } 149 | ctx.Set("globalAlpha", d.life) 150 | ctx.Set("strokeStyle", "orange") 151 | 152 | ctx.Call("beginPath") 153 | ctx.Call("moveTo", prevPos.x, prevPos.y) 154 | ctx.Call("lineTo", d.x, d.y) 155 | ctx.Call("stroke") 156 | } 157 | 158 | ht.ctx.Call("clearRect", 0, 0, ht.width, ht.height) 159 | ht.ctx.Set("globalAlpha", 1) 160 | ht.ctx.Call("drawImage", ctx.Get("canvas"), 0, 0) 161 | 162 | } 163 | 164 | func (ht *hexThing) dotReset(d *dot) { 165 | fH := math.Floor(ht.width / hexH) 166 | fW := math.Floor(ht.height / hexD) 167 | 168 | *d = dot{ 169 | pos: pos{ 170 | x: math.Floor(rand.Float64()*fH) * hexH, 171 | y: math.Floor(rand.Float64()*fW) * hexD, 172 | }, 173 | r: 0, 174 | dir: 90, 175 | life: 1 + rand.Float64(), 176 | } 177 | 178 | } 179 | func (ht *hexThing) SetNDots(n int) { 180 | ht.dots = make([]*dot, n) 181 | for i := 0; i < n; i++ { 182 | d := &dot{} 183 | ht.dotReset(d) 184 | ht.dots[i] = d 185 | } 186 | } 187 | 188 | type dot struct { 189 | pos 190 | r float64 191 | dir float64 192 | life float64 193 | } 194 | 195 | type pos struct { 196 | x float64 197 | y float64 198 | } 199 | -------------------------------------------------------------------------------- /hexy/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/hexy/main.wasm -------------------------------------------------------------------------------- /hexy/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | -------------------------------------------------------------------------------- /rainbow-mouse/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /rainbow-mouse/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - rainbow-mouse 4 | 5 | 6 | 7 | 8 | 25 | 33 | 34 | 35 |
36 |
37 |
38 | 39 |
40 | 41 | 42 | -------------------------------------------------------------------------------- /rainbow-mouse/main.go: -------------------------------------------------------------------------------- 1 | //Wasming 2 | // compile: GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 3 | package main 4 | 5 | import ( 6 | "math" 7 | "syscall/js" 8 | 9 | "github.com/lucasb-eyer/go-colorful" 10 | ) 11 | 12 | var ( 13 | mousePos [2]float64 14 | ctx js.Value 15 | ) 16 | 17 | func main() { 18 | 19 | doc := js.Global().Get("document") 20 | canvasEl := js.Global().Get("document").Call("getElementById", "mycanvas") 21 | 22 | bodyW := doc.Get("body").Get("clientWidth").Float() 23 | bodyH := doc.Get("body").Get("clientHeight").Float() 24 | canvasEl.Set("width", bodyW) 25 | canvasEl.Set("height", bodyH) 26 | ctx = canvasEl.Call("getContext", "2d") 27 | 28 | done := make(chan struct{}, 0) 29 | 30 | colorRot := float64(0) 31 | curPos := []float64{100, 75} 32 | 33 | mouseMoveEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 34 | e := args[0] 35 | mousePos[0] = e.Get("clientX").Float() 36 | mousePos[1] = e.Get("clientY").Float() 37 | return nil 38 | }) 39 | defer mouseMoveEvt.Release() 40 | 41 | doc.Call("addEventListener", "mousemove", mouseMoveEvt) 42 | 43 | var renderFrame js.Func 44 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 45 | // Handle window resizing 46 | curBodyW := doc.Get("body").Get("clientWidth").Float() 47 | curBodyH := doc.Get("body").Get("clientHeight").Float() 48 | if curBodyW != bodyW || curBodyH != bodyH { 49 | bodyW, bodyH = curBodyW, curBodyH 50 | canvasEl.Set("width", bodyW) 51 | canvasEl.Set("height", bodyH) 52 | } 53 | moveX := (mousePos[0] - curPos[0]) * 0.02 54 | moveY := (mousePos[1] - curPos[1]) * 0.02 55 | 56 | curPos[0] += moveX 57 | curPos[1] += moveY 58 | 59 | colorRot = float64(int(colorRot+1) % 360) 60 | ctx.Set("fillStyle", colorful.Hsv(colorRot, 1, 1).Hex()) 61 | ctx.Call("beginPath") 62 | ctx.Call("arc", curPos[0], curPos[1], 50, 0, 2*math.Pi) 63 | ctx.Call("fill") 64 | 65 | js.Global().Call("requestAnimationFrame", renderFrame) 66 | return nil 67 | }) 68 | defer renderFrame.Release() 69 | 70 | js.Global().Call("requestAnimationFrame", renderFrame) 71 | 72 | <-done 73 | } 74 | -------------------------------------------------------------------------------- /rainbow-mouse/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/rainbow-mouse/main.wasm -------------------------------------------------------------------------------- /rainbow-mouse/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | -------------------------------------------------------------------------------- /repulsion/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /repulsion/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - repulsion 4 | 5 | 6 | 7 | 8 | 34 | 59 | 60 | 61 |
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74 | 75 | 76 | -------------------------------------------------------------------------------- /repulsion/main.go: -------------------------------------------------------------------------------- 1 | //Wasming 2 | // compile: GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 3 | package main 4 | 5 | import ( 6 | "fmt" 7 | "math" 8 | "math/rand" 9 | "strconv" 10 | "syscall/js" 11 | ) 12 | 13 | var ( 14 | width float64 15 | height float64 16 | mousePos [2]float64 17 | ctx js.Value 18 | lineDistSq float64 = 100 * 100 19 | ) 20 | 21 | func main() { 22 | 23 | // Init Canvas stuff 24 | doc := js.Global().Get("document") 25 | canvasEl := doc.Call("getElementById", "mycanvas") 26 | width = doc.Get("body").Get("clientWidth").Float() 27 | height = doc.Get("body").Get("clientHeight").Float() 28 | canvasEl.Call("setAttribute", "width", width) 29 | canvasEl.Call("setAttribute", "height", height) 30 | ctx = canvasEl.Call("getContext", "2d") 31 | 32 | done := make(chan struct{}, 0) 33 | 34 | dt := DotThing{speed: 160} 35 | 36 | mouseMoveEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 37 | e := args[0] 38 | mousePos[0] = e.Get("clientX").Float() 39 | mousePos[1] = e.Get("clientY").Float() 40 | return nil 41 | }) 42 | defer mouseMoveEvt.Release() 43 | 44 | countChangeEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 45 | evt := args[0] 46 | intVal, err := strconv.Atoi(evt.Get("target").Get("value").String()) 47 | if err != nil { 48 | println("Invalid value", err) 49 | return nil 50 | } 51 | dt.SetNDots(intVal) 52 | return nil 53 | }) 54 | defer countChangeEvt.Release() 55 | 56 | speedInputEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 57 | evt := args[0] 58 | fval, err := strconv.ParseFloat(evt.Get("target").Get("value").String(), 64) 59 | if err != nil { 60 | println("Invalid value", err) 61 | return nil 62 | } 63 | dt.speed = fval 64 | return nil 65 | }) 66 | defer speedInputEvt.Release() 67 | 68 | // Handle mouse 69 | doc.Call("addEventListener", "mousemove", mouseMoveEvt) 70 | doc.Call("getElementById", "count").Call("addEventListener", "change", countChangeEvt) 71 | doc.Call("getElementById", "speed").Call("addEventListener", "input", speedInputEvt) 72 | 73 | dt.SetNDots(100) 74 | dt.lines = false 75 | var renderFrame js.Func 76 | var tmark float64 77 | var markCount = 0 78 | var tdiffSum float64 79 | 80 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 81 | now := args[0].Float() 82 | tdiff := now - tmark 83 | tdiffSum += now - tmark 84 | markCount++ 85 | if markCount > 10 { 86 | doc.Call("getElementById", "fps").Set("innerHTML", fmt.Sprintf("FPS: %.01f", 1000/(tdiffSum/float64(markCount)))) 87 | tdiffSum, markCount = 0, 0 88 | } 89 | tmark = now 90 | 91 | // Pool window size to handle resize 92 | curBodyW := doc.Get("body").Get("clientWidth").Float() 93 | curBodyH := doc.Get("body").Get("clientHeight").Float() 94 | if curBodyW != width || curBodyH != height { 95 | width, height = curBodyW, curBodyH 96 | canvasEl.Set("width", width) 97 | canvasEl.Set("height", height) 98 | } 99 | dt.Update(tdiff / 1000) 100 | 101 | js.Global().Call("requestAnimationFrame", renderFrame) 102 | return nil 103 | }) 104 | defer renderFrame.Release() 105 | 106 | // Start running 107 | js.Global().Call("requestAnimationFrame", renderFrame) 108 | 109 | <-done 110 | 111 | } 112 | 113 | // DotThing manager 114 | type DotThing struct { 115 | dots []*Dot 116 | lines bool 117 | speed float64 118 | } 119 | 120 | // Update updates the dot positions and draws 121 | func (dt *DotThing) Update(dtTime float64) { 122 | if dt.dots == nil { 123 | return 124 | } 125 | ctx.Call("clearRect", 0, 0, width, height) 126 | 127 | // Update 128 | for i, dot := range dt.dots { 129 | if dot.pos[0] < dot.size { 130 | dot.pos[0] = dot.size 131 | dot.dir[0] *= -1 132 | } 133 | if dot.pos[0] > width-dot.size { 134 | dot.pos[0] = width - dot.size 135 | dot.dir[0] *= -1 136 | } 137 | 138 | if dot.pos[1] < dot.size { 139 | dot.pos[1] = dot.size 140 | dot.dir[1] *= -1 141 | } 142 | 143 | if dot.pos[1] > height-dot.size { 144 | dot.pos[1] = height - dot.size 145 | dot.dir[1] *= -1 146 | } 147 | 148 | mdx := mousePos[0] - dot.pos[0] 149 | mdy := mousePos[1] - dot.pos[1] 150 | d := math.Sqrt(mdx*mdx + mdy*mdy) 151 | if d < 200 { 152 | dInv := 1 - d/200 153 | dot.dir[0] += (-mdx / d) * dInv * 8 154 | dot.dir[1] += (-mdy / d) * dInv * 8 155 | } 156 | for j, dot2 := range dt.dots { 157 | if i == j { 158 | continue 159 | } 160 | mx := dot2.pos[0] - dot.pos[0] 161 | my := dot2.pos[1] - dot.pos[1] 162 | d := math.Sqrt(mx*mx + my*my) 163 | if d < 100 { 164 | dInv := 1 - d/100 165 | dot.dir[0] += (-mx / d) * dInv 166 | dot.dir[1] += (-my / d) * dInv 167 | } 168 | } 169 | dot.dir[0] *= 0.1 //friction 170 | dot.dir[1] *= 0.1 //friction 171 | 172 | dot.pos[0] += dot.dir[0] * dt.speed * dtTime * 10 173 | dot.pos[1] += dot.dir[1] * dt.speed * dtTime * 10 174 | 175 | ctx.Set("globalAlpha", 0.5) 176 | ctx.Call("beginPath") 177 | ctx.Set("fillStyle", fmt.Sprintf("#%06x", dot.color)) 178 | ctx.Set("strokeStyle", fmt.Sprintf("#%06x", dot.color)) 179 | ctx.Set("lineWidth", dot.size) 180 | ctx.Call("arc", dot.pos[0], dot.pos[1], dot.size, 0, 2*math.Pi) 181 | ctx.Call("fill") 182 | 183 | } 184 | } 185 | 186 | // SetNDots reinitializes dots with n size 187 | func (dt *DotThing) SetNDots(n int) { 188 | dt.dots = make([]*Dot, n) 189 | for i := 0; i < n; i++ { 190 | dt.dots[i] = &Dot{ 191 | pos: [2]float64{ 192 | rand.Float64() * width, 193 | rand.Float64() * height, 194 | }, 195 | dir: [2]float64{ 196 | rand.NormFloat64(), 197 | rand.NormFloat64(), 198 | }, 199 | color: uint32(rand.Intn(0xFFFFFF)), 200 | size: 10, 201 | } 202 | } 203 | } 204 | 205 | // Dot represents a dot ... 206 | type Dot struct { 207 | pos [2]float64 208 | dir [2]float64 209 | color uint32 210 | size float64 211 | } 212 | -------------------------------------------------------------------------------- /repulsion/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/repulsion/main.wasm -------------------------------------------------------------------------------- /serve.go: -------------------------------------------------------------------------------- 1 | // Serve static files from current working directory 2 | // it will start at port 8080 if port is being used it will try next one 3 | package main 4 | 5 | import ( 6 | "fmt" 7 | "log" 8 | "net" 9 | "net/http" 10 | "os" 11 | ) 12 | 13 | func main() { 14 | port := 8080 15 | for { 16 | addr := fmt.Sprintf(":%d", port) 17 | listener, err := net.Listen("tcp", addr) 18 | if err != nil { 19 | fmt.Fprintln(os.Stderr, "err opening port", err) 20 | port++ 21 | continue 22 | } 23 | fmt.Printf("Listening at %s\n", addr) 24 | log.Fatal(http.Serve(listener, logger(http.FileServer(http.Dir("."))))) 25 | } 26 | } 27 | 28 | func logger(next http.Handler) http.HandlerFunc { 29 | return func(w http.ResponseWriter, r *http.Request) { 30 | fmt.Println(r.Method, r.URL.Path) 31 | next.ServeHTTP(w, r) 32 | } 33 | } 34 | -------------------------------------------------------------------------------- /splashy/build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | # Only works with go above 1.11beta1 current master (07-jun-2018) 3 | GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | -------------------------------------------------------------------------------- /splashy/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | go webassembly - splashy 4 | 5 | 6 | 7 | 8 | 33 | 58 | 59 | 60 |
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70 | 71 | 72 | -------------------------------------------------------------------------------- /splashy/main.go: -------------------------------------------------------------------------------- 1 | // Drag mouse on canvas 2 | //Wasming 3 | // compile: GOOS=js GOARCH=wasm go build -o main.wasm ./main.go 4 | package main 5 | 6 | import ( 7 | "fmt" 8 | "log" 9 | "math/rand" 10 | "strconv" 11 | 12 | "syscall/js" 13 | // this box2d throws some unexpected panics 14 | "github.com/ByteArena/box2d" 15 | 16 | colorful "github.com/lucasb-eyer/go-colorful" 17 | ) 18 | 19 | var ( 20 | width int 21 | height int 22 | ctx js.Value 23 | simSpeed = 1.0 24 | worldScale = 0.0125 25 | resDiv = 8 26 | maxBodies = 120 27 | ) 28 | 29 | func main() { 30 | 31 | // Init Canvas stuff 32 | doc := js.Global().Get("document") 33 | canvasEl := doc.Call("getElementById", "mycanvas") 34 | width = doc.Get("body").Get("clientWidth").Int() 35 | height = doc.Get("body").Get("clientHeight").Int() 36 | canvasEl.Set("width", width) 37 | canvasEl.Set("height", height) 38 | 39 | gl := canvasEl.Call("getContext", "webgl") 40 | if gl == js.Undefined() { 41 | gl = canvasEl.Call("getContext", "experimental-webgl") 42 | } 43 | // once again 44 | if gl == js.Undefined() { 45 | js.Global().Call("alert", "browser might not support webgl") 46 | return 47 | } 48 | 49 | done := make(chan struct{}, 0) 50 | 51 | thing := Thing{} 52 | mouseDown := false 53 | 54 | mouseDownEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 55 | mouseDown = true 56 | evt := args[0] 57 | if evt.Get("target") != canvasEl { 58 | return nil 59 | } 60 | mx := evt.Get("clientX").Float() * worldScale 61 | my := evt.Get("clientY").Float() * worldScale 62 | thing.AddCircle(mx, my) 63 | return nil 64 | }) 65 | defer mouseDownEvt.Release() 66 | 67 | mouseUpEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 68 | mouseDown = false 69 | return nil 70 | }) 71 | defer mouseUpEvt.Release() 72 | 73 | mouseMoveEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 74 | if !mouseDown { 75 | return nil 76 | } 77 | evt := args[0] 78 | if evt.Get("target") != canvasEl { 79 | return nil 80 | } 81 | mx := evt.Get("clientX").Float() * worldScale 82 | my := evt.Get("clientY").Float() * worldScale 83 | thing.AddCircle(mx, my) 84 | return nil 85 | }) 86 | defer mouseMoveEvt.Release() 87 | 88 | speedInputEvt := js.FuncOf(func(this js.Value, args []js.Value) interface{} { 89 | evt := args[0] 90 | fval, err := strconv.ParseFloat(evt.Get("target").Get("value").String(), 64) 91 | if err != nil { 92 | println("Invalid value", err) 93 | return nil 94 | } 95 | simSpeed = fval 96 | return nil 97 | }) 98 | defer speedInputEvt.Release() 99 | // Events 100 | doc.Call("addEventListener", "mousedown", mouseDownEvt) 101 | doc.Call("addEventListener", "mouseup", mouseUpEvt) 102 | doc.Call("addEventListener", "mousemove", mouseMoveEvt) 103 | doc.Call("getElementById", "speed").Call("addEventListener", "input", speedInputEvt) 104 | 105 | err := thing.Init(gl) 106 | if err != nil { 107 | println("Err Initializing thing:", err) 108 | return 109 | } 110 | 111 | // Draw things 112 | var renderFrame js.Func 113 | var tmark float64 114 | var markCount = 0 115 | var tdiffSum float64 116 | 117 | renderFrame = js.FuncOf(func(this js.Value, args []js.Value) interface{} { 118 | now := args[0].Float() 119 | tdiff := now - tmark 120 | tdiffSum += tdiff 121 | markCount++ 122 | if markCount > 10 { 123 | doc.Call("getElementById", "fps").Set("innerHTML", fmt.Sprintf("FPS: %.01f", 1000/(tdiffSum/float64(markCount)))) 124 | tdiffSum, markCount = 0, 0 125 | } 126 | tmark = now 127 | // -- 128 | thing.Render(gl, tdiff/1000) 129 | 130 | js.Global().Call("requestAnimationFrame", renderFrame) 131 | return nil 132 | }) 133 | defer renderFrame.Release() 134 | 135 | // Start running 136 | js.Global().Call("requestAnimationFrame", renderFrame) 137 | 138 | <-done 139 | 140 | } 141 | 142 | type Thing struct { 143 | // dot shaders 144 | prog js.Value 145 | aPosition js.Value 146 | uFragColor js.Value 147 | uResolution js.Value 148 | 149 | dotBuf js.Value 150 | qBlur *QuadFX 151 | qThreshold *QuadFX 152 | 153 | rtTex [2]js.Value // render target Texture 154 | rt [2]js.Value // framebuffer(render target) 155 | 156 | world box2d.B2World 157 | } 158 | 159 | func (t *Thing) Init(gl js.Value) error { 160 | // Drawing program 161 | var err error 162 | t.prog, err = programFromSrc(gl, dotVertShader, dotFragShader) 163 | if err != nil { 164 | return err 165 | } 166 | t.aPosition = gl.Call("getAttribLocation", t.prog, "a_position") 167 | t.uFragColor = gl.Call("getUniformLocation", t.prog, "uFragColor") 168 | t.uResolution = gl.Call("getUniformLocation", t.prog, "uResolution") 169 | 170 | t.dotBuf = gl.Call("createBuffer", gl.Get("ARRAY_BUFFER")) 171 | //renderer targets 172 | for i := 0; i < 2; i++ { 173 | t.rtTex[i] = createTexture(gl, width/resDiv, height/resDiv) 174 | t.rt[i] = createFB(gl, t.rtTex[i]) 175 | } 176 | 177 | t.qBlur = &QuadFX{} 178 | err = t.qBlur.Init(gl, blurShader) 179 | if err != nil { 180 | log.Fatal("Error:", err) 181 | } 182 | t.qThreshold = &QuadFX{} 183 | err = t.qThreshold.Init(gl, thresholdShader) 184 | if err != nil { 185 | log.Fatal("Error:", err) 186 | } 187 | 188 | ////////////////////////// 189 | // Physics 190 | // /////////// 191 | t.world = box2d.MakeB2World(box2d.B2Vec2{X: 0, Y: 9.8}) 192 | floor := t.world.CreateBody(&box2d.B2BodyDef{ 193 | Type: box2d.B2BodyType.B2_kinematicBody, 194 | Position: box2d.B2Vec2{X: 0, Y: float64(height+10) * worldScale}, 195 | Active: true, 196 | }) 197 | floorShape := &box2d.B2PolygonShape{} 198 | floorShape.SetAsBox(float64(width)*worldScale, 20*worldScale) 199 | ft := floor.CreateFixture(floorShape, 1) 200 | ft.M_friction = 0.3 201 | 202 | // Walls 203 | wallShape := &box2d.B2PolygonShape{} 204 | wallShape.SetAsBox(20*worldScale, float64(height)*worldScale) 205 | 206 | wallL := t.world.CreateBody(&box2d.B2BodyDef{ 207 | Type: box2d.B2BodyType.B2_kinematicBody, 208 | Position: box2d.B2Vec2{X: 0, Y: 0}, 209 | Active: true, 210 | }) 211 | wlf := wallL.CreateFixture(wallShape, 1) 212 | wlf.M_friction = 0.3 213 | 214 | wallR := t.world.CreateBody(&box2d.B2BodyDef{ 215 | Type: box2d.B2BodyType.B2_kinematicBody, 216 | Position: box2d.B2Vec2{X: float64(width) * worldScale, Y: 0}, 217 | Active: true, 218 | }) 219 | wrt := wallR.CreateFixture(wallShape, 1) 220 | wrt.M_friction = 0.3 221 | 222 | for i := 0; i < 10; i++ { 223 | t.AddCircle(rand.Float64()*float64(width)*worldScale, rand.Float64()*float64(height)*worldScale) 224 | } 225 | 226 | return nil 227 | } 228 | 229 | func (t *Thing) Render(gl js.Value, dtTime float64) { 230 | 231 | texWidth := width / resDiv 232 | texHeight := height / resDiv 233 | t.world.Step(dtTime*simSpeed, 3, 3) 234 | 235 | gl.Call("bindFramebuffer", gl.Get("FRAMEBUFFER"), t.rt[0]) 236 | gl.Call("viewport", 0, 0, texWidth, texHeight) //texSize 237 | gl.Call("clearColor", 0, 0, 0, 0) 238 | gl.Call("clear", gl.Get("COLOR_BUFFER_BIT")) 239 | 240 | // DotRenderer 241 | gl.Call("useProgram", t.prog) 242 | 243 | count := 0 244 | for curBody := t.world.GetBodyList(); curBody != nil; curBody = curBody.M_next { 245 | ft := curBody.M_fixtureList 246 | if _, ok := ft.M_shape.(*box2d.B2CircleShape); !ok { 247 | continue 248 | } 249 | x := float32(curBody.M_xf.P.X / (float64(width) * worldScale)) /* 0-1 */ 250 | y := float32(curBody.M_xf.P.Y / (float64(height) * worldScale)) /*0-1*/ 251 | 252 | col := colorful.Hsv(float64(360*count/maxBodies), 1, 1) 253 | gl.Call("vertexAttrib2f", t.aPosition, x, y) 254 | gl.Call("uniform4f", t.uFragColor, col.R, col.G, col.B, 1.0) 255 | gl.Call("drawArrays", gl.Get("POINTS"), 0, 1) 256 | 257 | count++ 258 | // Stop processing 259 | if count > maxBodies { 260 | break 261 | } 262 | } 263 | 264 | /// FX Blurx4 TODO: better blur 265 | for i := 0; i < 4; i++ { 266 | gl.Call("bindFramebuffer", gl.Get("FRAMEBUFFER"), t.rt[1]) 267 | gl.Call("viewport", 0, 0, texWidth, texHeight) 268 | gl.Call("bindTexture", gl.Get("TEXTURE_2D"), t.rtTex[0]) 269 | t.qBlur.Render(gl) 270 | 271 | gl.Call("bindFramebuffer", gl.Get("FRAMEBUFFER"), t.rt[0]) 272 | gl.Call("viewport", 0, 0, texWidth, texHeight) 273 | gl.Call("bindTexture", gl.Get("TEXTURE_2D"), t.rtTex[1]) 274 | t.qBlur.Render(gl) 275 | } 276 | 277 | /// FX Threshold to Screen 278 | gl.Call("bindFramebuffer", gl.Get("FRAMEBUFFER"), nil) 279 | gl.Call("viewport", 0, 0, width, height) 280 | gl.Call("bindTexture", gl.Get("TEXTURE_2D"), t.rtTex[0]) 281 | t.qThreshold.Render(gl) 282 | 283 | } 284 | 285 | func (t *Thing) AddCircle(mx, my float64) { 286 | if t.world.GetBodyCount() > maxBodies { 287 | // Check for the last on list and delete backwards:o 288 | var b *box2d.B2Body 289 | // theres is no M_last but we could cache it somewhere 290 | for b = t.world.GetBodyList(); b.M_next != nil; b = b.M_next { 291 | } 292 | // Search backwards for a circle (ignoring the walls/floors) 293 | for ; b != nil; b = b.M_prev { 294 | if _, ok := b.M_fixtureList.M_shape.(*box2d.B2CircleShape); ok { 295 | t.world.DestroyBody(b) // Destroy first found body 296 | break 297 | } 298 | } 299 | } 300 | obj1 := t.world.CreateBody(&box2d.B2BodyDef{ 301 | Type: box2d.B2BodyType.B2_dynamicBody, 302 | Position: box2d.B2Vec2{X: mx, Y: my}, 303 | Awake: true, 304 | Active: true, 305 | GravityScale: 1.0, 306 | }) 307 | shape := box2d.NewB2CircleShape() 308 | shape.M_radius = 10 * worldScale 309 | ft := obj1.CreateFixture(shape, 1) 310 | ft.M_friction = 0.2 311 | ft.M_restitution = 0.6 312 | } 313 | 314 | //// SHADERS & Utils 315 | const dotVertShader = ` 316 | attribute vec4 a_position; 317 | void main () { 318 | vec4 lpos= vec4(a_position.xy*2.0-1.0, 0, 1); 319 | lpos.y = -lpos.y; 320 | gl_Position = lpos; 321 | gl_PointSize = 22.0/4.0; 322 | } 323 | ` 324 | const dotFragShader = ` 325 | precision mediump float; 326 | uniform vec4 uFragColor; 327 | void main () { 328 | vec2 pt = gl_PointCoord - vec2(0.5); 329 | if(pt.x*pt.x+pt.y*pt.y > 0.25) 330 | discard; 331 | gl_FragColor = uFragColor; 332 | } 333 | ` 334 | 335 | const blurShader = ` 336 | precision mediump float; 337 | uniform sampler2D u_image; 338 | uniform vec2 u_textureSize; 339 | varying vec2 v_texCoord; 340 | void main() { 341 | vec2 onePixel = vec2(1,1) / u_textureSize; 342 | vec4 colorSum = 343 | texture2D(u_image, v_texCoord + onePixel * vec2(-1, -1)) + 344 | texture2D(u_image, v_texCoord + onePixel * vec2( 0, -1)) + 345 | texture2D(u_image, v_texCoord + onePixel * vec2( 1, -1)) + 346 | texture2D(u_image, v_texCoord + onePixel * vec2(-1, 0)) + 347 | texture2D(u_image, v_texCoord + onePixel * vec2( 0, 0)) + 348 | texture2D(u_image, v_texCoord + onePixel * vec2( 1, 0)) + 349 | texture2D(u_image, v_texCoord + onePixel * vec2(-1, 1)) + 350 | texture2D(u_image, v_texCoord + onePixel * vec2( 0, 1)) + 351 | texture2D(u_image, v_texCoord + onePixel * vec2( 1, 1)); 352 | gl_FragColor = colorSum / 9.0; 353 | } 354 | ` 355 | 356 | const thresholdShader = ` 357 | precision mediump float; 358 | uniform sampler2D u_image; 359 | uniform vec2 u_textureSize; 360 | varying vec2 v_texCoord; 361 | void main() { 362 | float a; 363 | vec2 onePixel = vec2(1,1) / u_textureSize; 364 | vec4 col = texture2D(u_image,v_texCoord); 365 | if (col.a < 0.4) discard; 366 | if (col.a < 0.8 && col.a > 0.72) { 367 | a = texture2D(u_image, v_texCoord + onePixel * vec2(-1, 1)).a; 368 | if (a < col.a ) { 369 | col += 0.4; 370 | } 371 | } 372 | gl_FragColor = vec4(col.rgb,1.0); 373 | } 374 | ` 375 | 376 | const vertQuad = ` 377 | attribute vec2 a_position; 378 | attribute vec2 a_texCoord; 379 | varying vec2 v_texCoord; 380 | void main() { 381 | gl_Position = vec4((a_position * 2.0 - 1.0), 0, 1); 382 | v_texCoord = a_texCoord; 383 | } 384 | ` 385 | 386 | type QuadFX struct { 387 | prog js.Value 388 | aPosition js.Value 389 | aTexCoord js.Value 390 | uTextureSize js.Value 391 | 392 | quadBuf js.Value 393 | 394 | vertexData js.Value 395 | } 396 | 397 | func (q *QuadFX) Init(gl js.Value, frag string) error { 398 | var err error 399 | q.prog, err = programFromSrc(gl, vertQuad, frag) 400 | if err != nil { 401 | return err 402 | } 403 | vertexData := []float32{ 404 | 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 405 | 0.0, 1.0, 1.0, 0.0, 1.0, 1.0, 406 | } 407 | // go1.13 removed TypedArrayOf https://github.com/golang/go/issues/31980 408 | q.vertexData = js.Global().Get("Float32Array").New(12) 409 | for i, v := range vertexData { 410 | q.vertexData.SetIndex(i, v) 411 | } 412 | 413 | q.aPosition = gl.Call("getAttribLocation", q.prog, "a_position") 414 | q.aTexCoord = gl.Call("getAttribLocation", q.prog, "a_texCoord") 415 | q.uTextureSize = gl.Call("getUniformLocation", q.prog, "u_textureSize") 416 | 417 | q.quadBuf = gl.Call("createBuffer") 418 | // texCoord/posCoord 419 | gl.Call("bindBuffer", gl.Get("ARRAY_BUFFER"), q.quadBuf) 420 | gl.Call("bufferData", gl.Get("ARRAY_BUFFER"), q.vertexData, gl.Get("STATIC_DRAW")) 421 | return nil 422 | 423 | } 424 | func (q *QuadFX) Render(gl js.Value) { 425 | gl.Call("useProgram", q.prog) 426 | // Vertex 427 | gl.Call("bindBuffer", gl.Get("ARRAY_BUFFER"), q.quadBuf) 428 | 429 | gl.Call("enableVertexAttribArray", q.aPosition) 430 | gl.Call("vertexAttribPointer", q.aPosition, 2, gl.Get("FLOAT"), false, 0, 0) 431 | gl.Call("enableVertexAttribArray", q.aTexCoord) // sabe buf 432 | gl.Call("vertexAttribPointer", q.aTexCoord, 2, gl.Get("FLOAT"), false, 0, 0) 433 | 434 | gl.Call("uniform2f", q.uTextureSize, width/resDiv, height/resDiv) 435 | 436 | gl.Call("drawArrays", gl.Get("TRIANGLES"), 0 /*offset*/, 6 /*count*/) 437 | gl.Call("disableVertexAttribArray", q.aPosition) 438 | gl.Call("disableVertexAttribArray", q.aTexCoord) 439 | 440 | } 441 | 442 | func (q *QuadFX) Release() { 443 | // TODO: gl release 444 | } 445 | 446 | // Helper funcs 447 | 448 | // Render to framebuffer first, then framebuffer to screen 449 | func compileShader(gl, shaderType js.Value, shaderSrc string) (js.Value, error) { 450 | var shader = gl.Call("createShader", shaderType) 451 | gl.Call("shaderSource", shader, shaderSrc) 452 | gl.Call("compileShader", shader) 453 | 454 | if !gl.Call("getShaderParameter", shader, gl.Get("COMPILE_STATUS")).Bool() { 455 | return js.Undefined(), fmt.Errorf("could not compile shader: %v", gl.Call("getShaderInfoLog", shader).String()) 456 | } 457 | return shader, nil 458 | } 459 | 460 | func linkProgram(gl, vertexShader, fragmentShader js.Value) (js.Value, error) { 461 | var program = gl.Call("createProgram") 462 | gl.Call("attachShader", program, vertexShader) 463 | gl.Call("attachShader", program, fragmentShader) 464 | gl.Call("linkProgram", program) 465 | if !gl.Call("getProgramParameter", program, gl.Get("LINK_STATUS")).Bool() { 466 | return js.Undefined(), fmt.Errorf("could not link program: %v", gl.Call("getProgramInfoLog", program).String()) 467 | } 468 | 469 | return program, nil 470 | } 471 | 472 | func programFromSrc(gl js.Value, vertShaderSrc, fragShaderSrc string) (js.Value, error) { 473 | vertexShader, err := compileShader(gl, gl.Get("VERTEX_SHADER"), vertShaderSrc) 474 | if err != nil { 475 | return js.Undefined(), err 476 | } 477 | fragShader, err := compileShader(gl, gl.Get("FRAGMENT_SHADER"), fragShaderSrc) 478 | if err != nil { 479 | return js.Undefined(), err 480 | } 481 | prog, err := linkProgram(gl, vertexShader, fragShader) 482 | if err != nil { 483 | return js.Undefined(), err 484 | } 485 | return prog, nil 486 | } 487 | 488 | func createTexture(gl js.Value, width, height int) js.Value { 489 | tex := gl.Call("createTexture") 490 | gl.Call("bindTexture", gl.Get("TEXTURE_2D"), tex) 491 | // define size and format of level 0 492 | gl.Call("texImage2D", 493 | gl.Get("TEXTURE_2D"), 494 | 0, 495 | gl.Get("RGBA"), 496 | width, height, 497 | 0, 498 | gl.Get("RGBA"), 499 | gl.Get("UNSIGNED_BYTE"), 500 | js.Null(), 501 | ) 502 | 503 | gl.Call("texParameteri", gl.Get("TEXTURE_2D"), gl.Get("TEXTURE_MIN_FILTER"), gl.Get("LINEAR")) 504 | gl.Call("texParameteri", gl.Get("TEXTURE_2D"), gl.Get("TEXTURE_MAG_FILTER"), gl.Get("LINEAR")) 505 | gl.Call("texParameteri", gl.Get("TEXTURE_2D"), gl.Get("TEXTURE_WRAP_S"), gl.Get("CLAMP_TO_EDGE")) 506 | gl.Call("texParameteri", gl.Get("TEXTURE_2D"), gl.Get("TEXTURE_WRAP_T"), gl.Get("CLAMP_TO_EDGE")) 507 | 508 | return tex 509 | } 510 | 511 | // Create framebuffer binded to texture 512 | func createFB(gl, tex js.Value) js.Value { 513 | fb := gl.Call("createFramebuffer") 514 | gl.Call("bindFramebuffer", gl.Get("FRAMEBUFFER"), fb) 515 | gl.Call("framebufferTexture2D", gl.Get("FRAMEBUFFER"), gl.Get("COLOR_ATTACHMENT0"), gl.Get("TEXTURE_2D"), tex, 0) 516 | return fb 517 | } 518 | -------------------------------------------------------------------------------- /splashy/main.wasm: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/stdiopt/gowasm-experiments/fe96c7b6247a5fa76c1008732a701313753647e5/splashy/main.wasm -------------------------------------------------------------------------------- /splashy/wasm_exec.js: -------------------------------------------------------------------------------- 1 | // Copyright 2018 The Go Authors. All rights reserved. 2 | // Use of this source code is governed by a BSD-style 3 | // license that can be found in the LICENSE file. 4 | 5 | (() => { 6 | // Map multiple JavaScript environments to a single common API, 7 | // preferring web standards over Node.js API. 8 | // 9 | // Environments considered: 10 | // - Browsers 11 | // - Node.js 12 | // - Electron 13 | // - Parcel 14 | 15 | if (typeof global !== "undefined") { 16 | // global already exists 17 | } else if (typeof window !== "undefined") { 18 | window.global = window; 19 | } else if (typeof self !== "undefined") { 20 | self.global = self; 21 | } else { 22 | throw new Error("cannot export Go (neither global, window nor self is defined)"); 23 | } 24 | 25 | if (!global.require && typeof require !== "undefined") { 26 | global.require = require; 27 | } 28 | 29 | if (!global.fs && global.require) { 30 | global.fs = require("fs"); 31 | } 32 | 33 | if (!global.fs) { 34 | let outputBuf = ""; 35 | global.fs = { 36 | constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused 37 | writeSync(fd, buf) { 38 | outputBuf += decoder.decode(buf); 39 | const nl = outputBuf.lastIndexOf("\n"); 40 | if (nl != -1) { 41 | console.log(outputBuf.substr(0, nl)); 42 | outputBuf = outputBuf.substr(nl + 1); 43 | } 44 | return buf.length; 45 | }, 46 | write(fd, buf, offset, length, position, callback) { 47 | if (offset !== 0 || length !== buf.length || position !== null) { 48 | throw new Error("not implemented"); 49 | } 50 | const n = this.writeSync(fd, buf); 51 | callback(null, n); 52 | }, 53 | open(path, flags, mode, callback) { 54 | const err = new Error("not implemented"); 55 | err.code = "ENOSYS"; 56 | callback(err); 57 | }, 58 | read(fd, buffer, offset, length, position, callback) { 59 | const err = new Error("not implemented"); 60 | err.code = "ENOSYS"; 61 | callback(err); 62 | }, 63 | fsync(fd, callback) { 64 | callback(null); 65 | }, 66 | }; 67 | } 68 | 69 | if (!global.crypto) { 70 | const nodeCrypto = require("crypto"); 71 | global.crypto = { 72 | getRandomValues(b) { 73 | nodeCrypto.randomFillSync(b); 74 | }, 75 | }; 76 | } 77 | 78 | if (!global.performance) { 79 | global.performance = { 80 | now() { 81 | const [sec, nsec] = process.hrtime(); 82 | return sec * 1000 + nsec / 1000000; 83 | }, 84 | }; 85 | } 86 | 87 | if (!global.TextEncoder) { 88 | global.TextEncoder = require("util").TextEncoder; 89 | } 90 | 91 | if (!global.TextDecoder) { 92 | global.TextDecoder = require("util").TextDecoder; 93 | } 94 | 95 | // End of polyfills for common API. 96 | 97 | const encoder = new TextEncoder("utf-8"); 98 | const decoder = new TextDecoder("utf-8"); 99 | 100 | global.Go = class { 101 | constructor() { 102 | this.argv = ["js"]; 103 | this.env = {}; 104 | this.exit = (code) => { 105 | if (code !== 0) { 106 | console.warn("exit code:", code); 107 | } 108 | }; 109 | this._exitPromise = new Promise((resolve) => { 110 | this._resolveExitPromise = resolve; 111 | }); 112 | this._pendingEvent = null; 113 | this._scheduledTimeouts = new Map(); 114 | this._nextCallbackTimeoutID = 1; 115 | 116 | const mem = () => { 117 | // The buffer may change when requesting more memory. 118 | return new DataView(this._inst.exports.mem.buffer); 119 | } 120 | 121 | const setInt64 = (addr, v) => { 122 | mem().setUint32(addr + 0, v, true); 123 | mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); 124 | } 125 | 126 | const getInt64 = (addr) => { 127 | const low = mem().getUint32(addr + 0, true); 128 | const high = mem().getInt32(addr + 4, true); 129 | return low + high * 4294967296; 130 | } 131 | 132 | const loadValue = (addr) => { 133 | const f = mem().getFloat64(addr, true); 134 | if (f === 0) { 135 | return undefined; 136 | } 137 | if (!isNaN(f)) { 138 | return f; 139 | } 140 | 141 | const id = mem().getUint32(addr, true); 142 | return this._values[id]; 143 | } 144 | 145 | const storeValue = (addr, v) => { 146 | const nanHead = 0x7FF80000; 147 | 148 | if (typeof v === "number") { 149 | if (isNaN(v)) { 150 | mem().setUint32(addr + 4, nanHead, true); 151 | mem().setUint32(addr, 0, true); 152 | return; 153 | } 154 | if (v === 0) { 155 | mem().setUint32(addr + 4, nanHead, true); 156 | mem().setUint32(addr, 1, true); 157 | return; 158 | } 159 | mem().setFloat64(addr, v, true); 160 | return; 161 | } 162 | 163 | switch (v) { 164 | case undefined: 165 | mem().setFloat64(addr, 0, true); 166 | return; 167 | case null: 168 | mem().setUint32(addr + 4, nanHead, true); 169 | mem().setUint32(addr, 2, true); 170 | return; 171 | case true: 172 | mem().setUint32(addr + 4, nanHead, true); 173 | mem().setUint32(addr, 3, true); 174 | return; 175 | case false: 176 | mem().setUint32(addr + 4, nanHead, true); 177 | mem().setUint32(addr, 4, true); 178 | return; 179 | } 180 | 181 | let ref = this._refs.get(v); 182 | if (ref === undefined) { 183 | ref = this._values.length; 184 | this._values.push(v); 185 | this._refs.set(v, ref); 186 | } 187 | let typeFlag = 0; 188 | switch (typeof v) { 189 | case "string": 190 | typeFlag = 1; 191 | break; 192 | case "symbol": 193 | typeFlag = 2; 194 | break; 195 | case "function": 196 | typeFlag = 3; 197 | break; 198 | } 199 | mem().setUint32(addr + 4, nanHead | typeFlag, true); 200 | mem().setUint32(addr, ref, true); 201 | } 202 | 203 | const loadSlice = (addr) => { 204 | const array = getInt64(addr + 0); 205 | const len = getInt64(addr + 8); 206 | return new Uint8Array(this._inst.exports.mem.buffer, array, len); 207 | } 208 | 209 | const loadSliceOfValues = (addr) => { 210 | const array = getInt64(addr + 0); 211 | const len = getInt64(addr + 8); 212 | const a = new Array(len); 213 | for (let i = 0; i < len; i++) { 214 | a[i] = loadValue(array + i * 8); 215 | } 216 | return a; 217 | } 218 | 219 | const loadString = (addr) => { 220 | const saddr = getInt64(addr + 0); 221 | const len = getInt64(addr + 8); 222 | return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); 223 | } 224 | 225 | const timeOrigin = Date.now() - performance.now(); 226 | this.importObject = { 227 | go: { 228 | // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) 229 | // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported 230 | // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). 231 | // This changes the SP, thus we have to update the SP used by the imported function. 232 | 233 | // func wasmExit(code int32) 234 | "runtime.wasmExit": (sp) => { 235 | const code = mem().getInt32(sp + 8, true); 236 | this.exited = true; 237 | delete this._inst; 238 | delete this._values; 239 | delete this._refs; 240 | this.exit(code); 241 | }, 242 | 243 | // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) 244 | "runtime.wasmWrite": (sp) => { 245 | const fd = getInt64(sp + 8); 246 | const p = getInt64(sp + 16); 247 | const n = mem().getInt32(sp + 24, true); 248 | fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); 249 | }, 250 | 251 | // func nanotime() int64 252 | "runtime.nanotime": (sp) => { 253 | setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); 254 | }, 255 | 256 | // func walltime() (sec int64, nsec int32) 257 | "runtime.walltime": (sp) => { 258 | const msec = (new Date).getTime(); 259 | setInt64(sp + 8, msec / 1000); 260 | mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); 261 | }, 262 | 263 | // func scheduleTimeoutEvent(delay int64) int32 264 | "runtime.scheduleTimeoutEvent": (sp) => { 265 | const id = this._nextCallbackTimeoutID; 266 | this._nextCallbackTimeoutID++; 267 | this._scheduledTimeouts.set(id, setTimeout( 268 | () => { 269 | this._resume(); 270 | while (this._scheduledTimeouts.has(id)) { 271 | // for some reason Go failed to register the timeout event, log and try again 272 | // (temporary workaround for https://github.com/golang/go/issues/28975) 273 | console.warn("scheduleTimeoutEvent: missed timeout event"); 274 | this._resume(); 275 | } 276 | }, 277 | getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early 278 | )); 279 | mem().setInt32(sp + 16, id, true); 280 | }, 281 | 282 | // func clearTimeoutEvent(id int32) 283 | "runtime.clearTimeoutEvent": (sp) => { 284 | const id = mem().getInt32(sp + 8, true); 285 | clearTimeout(this._scheduledTimeouts.get(id)); 286 | this._scheduledTimeouts.delete(id); 287 | }, 288 | 289 | // func getRandomData(r []byte) 290 | "runtime.getRandomData": (sp) => { 291 | crypto.getRandomValues(loadSlice(sp + 8)); 292 | }, 293 | 294 | // func stringVal(value string) ref 295 | "syscall/js.stringVal": (sp) => { 296 | storeValue(sp + 24, loadString(sp + 8)); 297 | }, 298 | 299 | // func valueGet(v ref, p string) ref 300 | "syscall/js.valueGet": (sp) => { 301 | const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); 302 | sp = this._inst.exports.getsp(); // see comment above 303 | storeValue(sp + 32, result); 304 | }, 305 | 306 | // func valueSet(v ref, p string, x ref) 307 | "syscall/js.valueSet": (sp) => { 308 | Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); 309 | }, 310 | 311 | // func valueIndex(v ref, i int) ref 312 | "syscall/js.valueIndex": (sp) => { 313 | storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); 314 | }, 315 | 316 | // valueSetIndex(v ref, i int, x ref) 317 | "syscall/js.valueSetIndex": (sp) => { 318 | Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); 319 | }, 320 | 321 | // func valueCall(v ref, m string, args []ref) (ref, bool) 322 | "syscall/js.valueCall": (sp) => { 323 | try { 324 | const v = loadValue(sp + 8); 325 | const m = Reflect.get(v, loadString(sp + 16)); 326 | const args = loadSliceOfValues(sp + 32); 327 | const result = Reflect.apply(m, v, args); 328 | sp = this._inst.exports.getsp(); // see comment above 329 | storeValue(sp + 56, result); 330 | mem().setUint8(sp + 64, 1); 331 | } catch (err) { 332 | storeValue(sp + 56, err); 333 | mem().setUint8(sp + 64, 0); 334 | } 335 | }, 336 | 337 | // func valueInvoke(v ref, args []ref) (ref, bool) 338 | "syscall/js.valueInvoke": (sp) => { 339 | try { 340 | const v = loadValue(sp + 8); 341 | const args = loadSliceOfValues(sp + 16); 342 | const result = Reflect.apply(v, undefined, args); 343 | sp = this._inst.exports.getsp(); // see comment above 344 | storeValue(sp + 40, result); 345 | mem().setUint8(sp + 48, 1); 346 | } catch (err) { 347 | storeValue(sp + 40, err); 348 | mem().setUint8(sp + 48, 0); 349 | } 350 | }, 351 | 352 | // func valueNew(v ref, args []ref) (ref, bool) 353 | "syscall/js.valueNew": (sp) => { 354 | try { 355 | const v = loadValue(sp + 8); 356 | const args = loadSliceOfValues(sp + 16); 357 | const result = Reflect.construct(v, args); 358 | sp = this._inst.exports.getsp(); // see comment above 359 | storeValue(sp + 40, result); 360 | mem().setUint8(sp + 48, 1); 361 | } catch (err) { 362 | storeValue(sp + 40, err); 363 | mem().setUint8(sp + 48, 0); 364 | } 365 | }, 366 | 367 | // func valueLength(v ref) int 368 | "syscall/js.valueLength": (sp) => { 369 | setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); 370 | }, 371 | 372 | // valuePrepareString(v ref) (ref, int) 373 | "syscall/js.valuePrepareString": (sp) => { 374 | const str = encoder.encode(String(loadValue(sp + 8))); 375 | storeValue(sp + 16, str); 376 | setInt64(sp + 24, str.length); 377 | }, 378 | 379 | // valueLoadString(v ref, b []byte) 380 | "syscall/js.valueLoadString": (sp) => { 381 | const str = loadValue(sp + 8); 382 | loadSlice(sp + 16).set(str); 383 | }, 384 | 385 | // func valueInstanceOf(v ref, t ref) bool 386 | "syscall/js.valueInstanceOf": (sp) => { 387 | mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); 388 | }, 389 | 390 | // func copyBytesToGo(dst []byte, src ref) (int, bool) 391 | "syscall/js.copyBytesToGo": (sp) => { 392 | const dst = loadSlice(sp + 8); 393 | const src = loadValue(sp + 32); 394 | if (!(src instanceof Uint8Array)) { 395 | mem().setUint8(sp + 48, 0); 396 | return; 397 | } 398 | const toCopy = src.subarray(0, dst.length); 399 | dst.set(toCopy); 400 | setInt64(sp + 40, toCopy.length); 401 | mem().setUint8(sp + 48, 1); 402 | }, 403 | 404 | // func copyBytesToJS(dst ref, src []byte) (int, bool) 405 | "syscall/js.copyBytesToJS": (sp) => { 406 | const dst = loadValue(sp + 8); 407 | const src = loadSlice(sp + 16); 408 | if (!(dst instanceof Uint8Array)) { 409 | mem().setUint8(sp + 48, 0); 410 | return; 411 | } 412 | const toCopy = src.subarray(0, dst.length); 413 | dst.set(toCopy); 414 | setInt64(sp + 40, toCopy.length); 415 | mem().setUint8(sp + 48, 1); 416 | }, 417 | 418 | "debug": (value) => { 419 | console.log(value); 420 | }, 421 | } 422 | }; 423 | } 424 | 425 | async run(instance) { 426 | this._inst = instance; 427 | this._values = [ // TODO: garbage collection 428 | NaN, 429 | 0, 430 | null, 431 | true, 432 | false, 433 | global, 434 | this, 435 | ]; 436 | this._refs = new Map(); 437 | this.exited = false; 438 | 439 | const mem = new DataView(this._inst.exports.mem.buffer) 440 | 441 | // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. 442 | let offset = 4096; 443 | 444 | const strPtr = (str) => { 445 | const ptr = offset; 446 | const bytes = encoder.encode(str + "\0"); 447 | new Uint8Array(mem.buffer, offset, bytes.length).set(bytes); 448 | offset += bytes.length; 449 | if (offset % 8 !== 0) { 450 | offset += 8 - (offset % 8); 451 | } 452 | return ptr; 453 | }; 454 | 455 | const argc = this.argv.length; 456 | 457 | const argvPtrs = []; 458 | this.argv.forEach((arg) => { 459 | argvPtrs.push(strPtr(arg)); 460 | }); 461 | 462 | const keys = Object.keys(this.env).sort(); 463 | argvPtrs.push(keys.length); 464 | keys.forEach((key) => { 465 | argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); 466 | }); 467 | 468 | const argv = offset; 469 | argvPtrs.forEach((ptr) => { 470 | mem.setUint32(offset, ptr, true); 471 | mem.setUint32(offset + 4, 0, true); 472 | offset += 8; 473 | }); 474 | 475 | this._inst.exports.run(argc, argv); 476 | if (this.exited) { 477 | this._resolveExitPromise(); 478 | } 479 | await this._exitPromise; 480 | } 481 | 482 | _resume() { 483 | if (this.exited) { 484 | throw new Error("Go program has already exited"); 485 | } 486 | this._inst.exports.resume(); 487 | if (this.exited) { 488 | this._resolveExitPromise(); 489 | } 490 | } 491 | 492 | _makeFuncWrapper(id) { 493 | const go = this; 494 | return function () { 495 | const event = { id: id, this: this, args: arguments }; 496 | go._pendingEvent = event; 497 | go._resume(); 498 | return event.result; 499 | }; 500 | } 501 | } 502 | 503 | if ( 504 | global.require && 505 | global.require.main === module && 506 | global.process && 507 | global.process.versions && 508 | !global.process.versions.electron 509 | ) { 510 | if (process.argv.length < 3) { 511 | console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); 512 | process.exit(1); 513 | } 514 | 515 | const go = new Go(); 516 | go.argv = process.argv.slice(2); 517 | go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); 518 | go.exit = process.exit; 519 | WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { 520 | process.on("exit", (code) => { // Node.js exits if no event handler is pending 521 | if (code === 0 && !go.exited) { 522 | // deadlock, make Go print error and stack traces 523 | go._pendingEvent = { id: 0 }; 524 | go._resume(); 525 | } 526 | }); 527 | return go.run(result.instance); 528 | }).catch((err) => { 529 | console.error(err); 530 | process.exit(1); 531 | }); 532 | } 533 | })(); 534 | --------------------------------------------------------------------------------