├── PencilController ├── DSCF0786.jpg ├── Assets.xcassets │ └── AppIcon.appiconset │ │ └── Contents.json ├── Info.plist ├── Base.lproj │ ├── Main.storyboard │ └── LaunchScreen.storyboard ├── AppDelegate.swift └── ViewController.swift ├── PencilController.xcodeproj ├── project.xcworkspace │ └── contents.xcworkspacedata ├── xcuserdata │ └── simongladman.xcuserdatad │ │ └── xcschemes │ │ ├── xcschememanagement.plist │ │ └── PencilController.xcscheme └── project.pbxproj └── README.md /PencilController/DSCF0786.jpg: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/FlexMonkey/PencilController/HEAD/PencilController/DSCF0786.jpg -------------------------------------------------------------------------------- /PencilController.xcodeproj/project.xcworkspace/contents.xcworkspacedata: -------------------------------------------------------------------------------- 1 | 2 | 4 | 6 | 7 | 8 | -------------------------------------------------------------------------------- /PencilController.xcodeproj/xcuserdata/simongladman.xcuserdatad/xcschemes/xcschememanagement.plist: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | SchemeUserState 6 | 7 | PencilController.xcscheme 8 | 9 | orderHint 10 | 0 11 | 12 | 13 | SuppressBuildableAutocreation 14 | 15 | 3EC2AEA51C005567005CBE16 16 | 17 | primary 18 | 19 | 20 | 21 | 22 | 23 | -------------------------------------------------------------------------------- /PencilController/Assets.xcassets/AppIcon.appiconset/Contents.json: -------------------------------------------------------------------------------- 1 | { 2 | "images" : [ 3 | { 4 | "idiom" : "ipad", 5 | "size" : "29x29", 6 | "scale" : "1x" 7 | }, 8 | { 9 | "idiom" : "ipad", 10 | "size" : "29x29", 11 | "scale" : "2x" 12 | }, 13 | { 14 | "idiom" : "ipad", 15 | "size" : "40x40", 16 | "scale" : "1x" 17 | }, 18 | { 19 | "idiom" : "ipad", 20 | "size" : "40x40", 21 | "scale" : "2x" 22 | }, 23 | { 24 | "idiom" : "ipad", 25 | "size" : "76x76", 26 | "scale" : "1x" 27 | }, 28 | { 29 | "idiom" : "ipad", 30 | "size" : "76x76", 31 | "scale" : "2x" 32 | } 33 | ], 34 | "info" : { 35 | "version" : 1, 36 | "author" : "xcode" 37 | } 38 | } -------------------------------------------------------------------------------- /PencilController/Info.plist: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | CFBundleDevelopmentRegion 6 | en 7 | CFBundleExecutable 8 | $(EXECUTABLE_NAME) 9 | CFBundleIdentifier 10 | $(PRODUCT_BUNDLE_IDENTIFIER) 11 | CFBundleInfoDictionaryVersion 12 | 6.0 13 | CFBundleName 14 | $(PRODUCT_NAME) 15 | CFBundlePackageType 16 | APPL 17 | CFBundleShortVersionString 18 | 1.0 19 | CFBundleSignature 20 | ???? 21 | CFBundleVersion 22 | 1 23 | LSRequiresIPhoneOS 24 | 25 | UILaunchStoryboardName 26 | LaunchScreen 27 | UIMainStoryboardFile 28 | Main 29 | UIRequiredDeviceCapabilities 30 | 31 | armv7 32 | 33 | UISupportedInterfaceOrientations~ipad 34 | 35 | UIInterfaceOrientationPortrait 36 | UIInterfaceOrientationPortraitUpsideDown 37 | UIInterfaceOrientationLandscapeLeft 38 | UIInterfaceOrientationLandscapeRight 39 | 40 | 41 | 42 | -------------------------------------------------------------------------------- /PencilController/Base.lproj/Main.storyboard: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | -------------------------------------------------------------------------------- /PencilController/Base.lproj/LaunchScreen.storyboard: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | -------------------------------------------------------------------------------- /PencilController/AppDelegate.swift: -------------------------------------------------------------------------------- 1 | // 2 | // AppDelegate.swift 3 | // PencilController 4 | // 5 | // Created by Simon Gladman on 21/11/2015. 6 | // Copyright © 2015 Simon Gladman. All rights reserved. 7 | // 8 | 9 | import UIKit 10 | 11 | @UIApplicationMain 12 | class AppDelegate: UIResponder, UIApplicationDelegate { 13 | 14 | var window: UIWindow? 15 | 16 | 17 | func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { 18 | // Override point for customization after application launch. 19 | return true 20 | } 21 | 22 | func applicationWillResignActive(application: UIApplication) { 23 | // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state. 24 | // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game. 25 | } 26 | 27 | func applicationDidEnterBackground(application: UIApplication) { 28 | // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later. 29 | // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits. 30 | } 31 | 32 | func applicationWillEnterForeground(application: UIApplication) { 33 | // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background. 34 | } 35 | 36 | func applicationDidBecomeActive(application: UIApplication) { 37 | // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface. 38 | } 39 | 40 | func applicationWillTerminate(application: UIApplication) { 41 | // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:. 42 | } 43 | 44 | 45 | } 46 | 47 | -------------------------------------------------------------------------------- /PencilController.xcodeproj/xcuserdata/simongladman.xcuserdatad/xcschemes/PencilController.xcscheme: -------------------------------------------------------------------------------- 1 | 2 | 5 | 8 | 9 | 15 | 21 | 22 | 23 | 24 | 25 | 30 | 31 | 32 | 33 | 39 | 40 | 41 | 42 | 43 | 44 | 54 | 56 | 62 | 63 | 64 | 65 | 66 | 67 | 73 | 75 | 81 | 82 | 83 | 84 | 86 | 87 | 90 | 91 | 92 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # PencilController 2 | ##### Using Apple Pencil as a 3D Controller for Image Editing 3 | 4 | ##### _Companion project to this blog post: http://flexmonkey.blogspot.co.uk/2015/11/pencilcontroller-using-apple-pencil-as.html_ 5 | 6 | Despite Jony Ive describing the Pencil as being designed for marking and not as a stylus finger replacement in Wallpaper*, I've decided to explore a few unconventional uses for mine. Yesterday saw a slightly ramshackle looking Pencil based electronic scale and today I'm using it as a joystick of sorts for controlling parameters on image filters. 7 | 8 | My PencilController project is a Swift app for iPad Pro that applies two Core Image filters to an image: a hue adjustment and a colour controls which I use to control the saturation. 9 | 10 | The Pencil's orientation in space is described by the Horizontal Coordinate System with azimuth and altitude angles. 11 | 12 | The hue filter's value is controlled by the azimuth angle and the saturation is controlled by the altitude angle: when the pencil is vertical, the saturation is zero and when it's horizontal the saturation is eight (although when the pencil is totally horizontal, its tip isn't actually touching the screen, so the highest saturation the app can set is about six and three quarters). 13 | 14 | To jazz up the user interface, I've also added a rounded cylinder using SceneKit which mirrors the Pencil's position and orientation. 15 | 16 | ## Controlling Core Image Filter Parameters with Pencil 17 | 18 | Setting the values for the two Core Image filters is pretty simple stuff. Both filters are declared as constants at the top of my view controller along with a Core Image context (without colour management for performance) and a Core Image image: 19 | 20 | ```swift 21 | let hueAdjust = CIFilter(name: "CIHueAdjust")! 22 | let colorControls = CIFilter(name: "CIColorControls")! 23 | 24 | let ciContext = CIContext(EAGLContext: EAGLContext(API: EAGLRenderingAPI.OpenGLES2), 25 | options: [kCIContextWorkingColorSpace: NSNull()]) 26 | 27 | let coreImage = CIImage(image: UIImage(named: "DSCF0786.jpg")!)! 28 | ``` 29 | 30 | When the touch either starts or changes, I want to ensure it originates from a Pencil by checking its type and then invoke `applyFilter()` via `pencilTouchHandler()` method: 31 | 32 | ```swift 33 | override func touchesMoved(touches: Set, withEvent event: UIEvent?) 34 | { 35 | guard let touch = touches.first where 36 | touch.type == UITouchType.Stylus else 37 | { 38 | return 39 | } 40 | 41 | pencilTouchHandler(touch) 42 | } 43 | ``` 44 | 45 | `pencilTouchHandler()` extracts the azimuth and altitude angles from the `UITouch`, does some simple arithmetic and passes those values to `applyFilter()`: 46 | 47 | ```swift 48 | applyFilter(hueAngle: pi + touch.azimuthAngleInView(view), 49 | saturation: 8 * ((halfPi - touch.altitudeAngle) / halfPi)) 50 | ``` 51 | 52 | It's `applyFilter()` that uses those two values to set the parameters on the filters and display the output in a UIImageView: 53 | 54 | ```swift 55 | func applyFilter(hueAngle hueAngle: CGFloat, saturation: CGFloat) 56 | { 57 | hueAdjust.setValue(coreImage, 58 | forKey: kCIInputImageKey) 59 | hueAdjust.setValue(hueAngle, 60 | forKey: kCIInputAngleKey) 61 | 62 | colorControls.setValue(hueAdjust.valueForKey(kCIOutputImageKey) as! CIImage, 63 | forKey: kCIInputImageKey) 64 | colorControls.setValue(saturation, 65 | forKey: kCIInputSaturationKey) 66 | 67 | let cgImage = ciContext.createCGImage(colorControls.valueForKey(kCIOutputImageKey) as! CIImage, 68 | fromRect: coreImage.extent) 69 | 70 | imageView.image = UIImage(CGImage: cgImage) 71 | 72 | label.text = String(format: "Hue: %.2f°", hueAngle * 180 / pi) + " " + String(format: "Saturation: %.2f", saturation) 73 | } 74 | ``` 75 | 76 | On my iPad Pro this filtering is fast enough on a near full screen image that I don't have to worry about doing this work in a background thread. 77 | 78 | ## Controlling SceneKit Geometry with Pencil 79 | 80 | The next piece of work is to orient and position the "virtual pencil" so it mirrors the real one. I've overlaid a `SCNView` above the `UIImageView` and added a capsule geometry (which is a cylinder with rounded ends, not unlike a Pencil). Importantly, I've also added a flat plane which is used to capture the Pencil's location in the SceneKit 3D space: 81 | 82 | ```swift 83 | let sceneKitView = SCNView() 84 | let scene = SCNScene() 85 | let cylinderNode = SCNNode(geometry: SCNCapsule(capRadius: 0.05, height: 1)) 86 | let plane = SCNNode(geometry: SCNPlane(width: 20, height: 20)) 87 | 88 | // in init() 89 | sceneKitView.scene = scene 90 | scene.rootNode.addChildNode(cameraNode) 91 | scene.rootNode.addChildNode(cylinderNode) 92 | scene.rootNode.addChildNode(plane) 93 | ``` 94 | 95 | Inside the `pencilTouchHandler()`, I use the SceneKit view's `hitTest()` method to find the x and y positions of the Pencil on the screen in SceneKit's 3D space on the plane: 96 | 97 | ```swift 98 | func pencilTouchHandler(touch: UITouch) 99 | { 100 | guard let hitTestResult:SCNHitTestResult = sceneKitView.hitTest(touch.locationInView(view), options: nil) 101 | .filter( { $0.node == plane }) 102 | .first else 103 | { 104 | return 105 | } 106 | [...] 107 | ``` 108 | 109 | ...and with the results of that hit test, I can position the cylinder underneath the Pencil's touch location: 110 | 111 | ```swift 112 | [...] 113 | cylinderNode.position = SCNVector3(hitTestResult.localCoordinates.x, 114 | hitTestResult.localCoordinates.y, 115 | 0) 116 | [...] 117 | ``` 118 | 119 | Finally, with the altitude and azimuth angles of the touch, I can set the Euler angles of the cylinder to match the Pencil: 120 | 121 | ```swift 122 | [...] 123 | cylinderNode.eulerAngles = SCNVector3(touch.altitudeAngle, 124 | 0.0, 125 | 0 - touch.azimuthAngleInView(view) - halfPi) 126 | [...] 127 | ``` 128 | 129 | I've made the SceneKit camera orthographic, a perspective camera adds unwanted rotation to the "virtual pencil" as it moves across the screen. 130 | 131 | ## Conclusion 132 | 133 | Despite what Jony Ive may say, the Pencil offers some user interaction patterns impossible with a simple touch screen and I hope other developers start exploring new ideas. In addition to the two angles, the Pencil also has x and y coordinates and its force, so that's five different values that could potentially be used for controlling anything, from image filters to an audio synthesiser! 134 | 135 | As always, the source code for this project is available at my GitHub repository here. 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283 | defaultConfigurationIsVisible = 0; 284 | defaultConfigurationName = Release; 285 | }; 286 | 3EC2AEB81C005567005CBE16 /* Build configuration list for PBXNativeTarget "PencilController" */ = { 287 | isa = XCConfigurationList; 288 | buildConfigurations = ( 289 | 3EC2AEB91C005567005CBE16 /* Debug */, 290 | 3EC2AEBA1C005567005CBE16 /* Release */, 291 | ); 292 | defaultConfigurationIsVisible = 0; 293 | }; 294 | /* End XCConfigurationList section */ 295 | }; 296 | rootObject = 3EC2AE9E1C005567005CBE16 /* Project object */; 297 | } 298 | -------------------------------------------------------------------------------- /PencilController/ViewController.swift: -------------------------------------------------------------------------------- 1 | // 2 | // ViewController.swift 3 | // PencilController 4 | // 5 | // Created by Simon Gladman on 21/11/2015. 6 | // Copyright © 2015 Simon Gladman. All rights reserved. 7 | // 8 | 9 | import UIKit 10 | import SceneKit 11 | 12 | class ViewController: UIViewController 13 | { 14 | let label = UILabel() 15 | 16 | let halfPi = CGFloat(M_PI_2) 17 | let pi = CGFloat(M_PI) 18 | 19 | let ciContext = CIContext(EAGLContext: EAGLContext(API: EAGLRenderingAPI.OpenGLES2), 20 | options: [kCIContextWorkingColorSpace: NSNull()]) 21 | 22 | let coreImage = CIImage(image: UIImage(named: "DSCF0786.jpg")!)! 23 | 24 | let imageView = UIImageView() 25 | 26 | let sceneKitView = SCNView() 27 | let scene = SCNScene() 28 | let cylinderNode = SCNNode(geometry: SCNCapsule(capRadius: 0.05, height: 1)) 29 | let plane = SCNNode(geometry: SCNPlane(width: 20, height: 20)) 30 | 31 | let hueAdjust = CIFilter(name: "CIHueAdjust")! 32 | let colorControls = CIFilter(name: "CIColorControls")! 33 | let gammaAdjust = CIFilter(name: "CIGammaAdjust")! 34 | let exposureAdjust = CIFilter(name: "CIExposureAdjust")! 35 | 36 | let hueSaturationButton = ChunkyButton(title: "Hue\nSaturation", filteringMode: .HueSaturation) 37 | let brightnessContrastButton = ChunkyButton(title: "Brightness\nContrast", filteringMode: .BrightnessContrast) 38 | let gammaExposureButton = ChunkyButton(title: "Gamma\nExposure", filteringMode: .GammaExposure) 39 | 40 | var hueAngle: CGFloat = 0 41 | var saturation: CGFloat = 1 42 | var brightness: CGFloat = 0 43 | var contrast: CGFloat = 1 44 | var gamma: CGFloat = 1 45 | var exposure: CGFloat = 0 46 | 47 | var pencilOn = false 48 | 49 | var filteringMode = FilteringMode.Off 50 | { 51 | didSet 52 | { 53 | label.hidden = filteringMode == .Off 54 | } 55 | } 56 | 57 | override func viewDidLoad() 58 | { 59 | super.viewDidLoad() 60 | 61 | view.backgroundColor = UIColor.blackColor() 62 | 63 | view.addSubview(imageView) 64 | view.addSubview(label) 65 | view.addSubview(sceneKitView) 66 | 67 | view.addSubview(hueSaturationButton) 68 | view.addSubview(brightnessContrastButton) 69 | view.addSubview(gammaExposureButton) 70 | 71 | label.font = UIFont.monospacedDigitSystemFontOfSize(36, weight: UIFontWeightSemibold) 72 | 73 | label.textAlignment = NSTextAlignment.Center 74 | label.text = "flexmonkey.blogspot.co.uk" 75 | label.textColor = UIColor.whiteColor() 76 | label.hidden = true 77 | 78 | imageView.contentMode = UIViewContentMode.Center 79 | 80 | sceneKitView.scene = scene 81 | sceneKitView.backgroundColor = UIColor.clearColor() 82 | addLights() 83 | 84 | let camera = SCNCamera() 85 | camera.usesOrthographicProjection = true 86 | 87 | camera.xFov = 45 88 | camera.yFov = 45 89 | 90 | let cameraNode = SCNNode() 91 | 92 | cameraNode.camera = camera 93 | cameraNode.position = SCNVector3(x: 0, y: 0, z: 20) 94 | 95 | cylinderNode.position = SCNVector3(0, 0, 0) 96 | cylinderNode.pivot = SCNMatrix4MakeTranslation(0, 0.5, 0) 97 | 98 | plane.opacity = 0.000001 99 | 100 | scene.rootNode.addChildNode(cameraNode) 101 | scene.rootNode.addChildNode(cylinderNode) 102 | scene.rootNode.addChildNode(plane) 103 | 104 | cylinderNode.opacity = 0 105 | 106 | applyFilter() 107 | 108 | hueSaturationButton.addTarget(self, action: "filterButtonTouchDown:", forControlEvents: UIControlEvents.TouchDown) 109 | hueSaturationButton.addTarget(self, action: "filterButtonTouchEnded:", forControlEvents: UIControlEvents.TouchUpInside) 110 | 111 | brightnessContrastButton.addTarget(self, action: "filterButtonTouchDown:", forControlEvents: UIControlEvents.TouchDown) 112 | brightnessContrastButton.addTarget(self, action: "filterButtonTouchEnded:", forControlEvents: UIControlEvents.TouchUpInside) 113 | 114 | gammaExposureButton.addTarget(self, action: "filterButtonTouchDown:", forControlEvents: UIControlEvents.TouchDown) 115 | gammaExposureButton.addTarget(self, action: "filterButtonTouchEnded:", forControlEvents: UIControlEvents.TouchUpInside) 116 | } 117 | 118 | func filterButtonTouchDown(button: ChunkyButton) 119 | { 120 | filteringMode = button.filteringMode 121 | 122 | updateLabel() 123 | 124 | if pencilOn 125 | { 126 | SCNTransaction.setAnimationDuration(0.25) 127 | cylinderNode.opacity = 1 128 | } 129 | } 130 | 131 | func filterButtonTouchEnded(button: ChunkyButton) 132 | { 133 | filteringMode = .Off 134 | 135 | SCNTransaction.setAnimationDuration(0.25) 136 | cylinderNode.opacity = 0 137 | } 138 | 139 | override func touchesBegan(touches: Set, withEvent event: UIEvent?) 140 | { 141 | guard let touch = touches.first where 142 | filteringMode != .Off && 143 | touch.type == UITouchType.Stylus else 144 | { 145 | return 146 | } 147 | 148 | pencilOn = true 149 | 150 | pencilTouchHandler(touch) 151 | 152 | SCNTransaction.setAnimationDuration(0.25) 153 | cylinderNode.opacity = 1 154 | } 155 | 156 | override func touchesMoved(touches: Set, withEvent event: UIEvent?) 157 | { 158 | guard let touch = touches.first where 159 | filteringMode != .Off && 160 | touch.type == UITouchType.Stylus else 161 | { 162 | return 163 | } 164 | 165 | pencilTouchHandler(touch) 166 | } 167 | 168 | override func touchesEnded(touches: Set, withEvent event: UIEvent?) 169 | { 170 | guard touches.first?.type == UITouchType.Stylus else 171 | { 172 | return 173 | } 174 | 175 | pencilOn = false 176 | SCNTransaction.setAnimationDuration(0.25) 177 | cylinderNode.opacity = 0 178 | } 179 | 180 | func pencilTouchHandler(touch: UITouch) 181 | { 182 | guard let hitTestResult:SCNHitTestResult = sceneKitView.hitTest(touch.locationInView(view), options: nil).filter( { $0.node == plane }).first else 183 | { 184 | return 185 | } 186 | 187 | SCNTransaction.setAnimationDuration(0) 188 | 189 | cylinderNode.position = SCNVector3(hitTestResult.localCoordinates.x, hitTestResult.localCoordinates.y, 0) 190 | cylinderNode.eulerAngles = SCNVector3(touch.altitudeAngle, 0.0, 0 - touch.azimuthAngleInView(view) - halfPi) 191 | 192 | switch filteringMode 193 | { 194 | case .HueSaturation: 195 | hueAngle = pi + touch.azimuthAngleInView(view) 196 | saturation = 8 * ((halfPi - touch.altitudeAngle) / halfPi) 197 | 198 | case .BrightnessContrast: 199 | brightness = touch.azimuthUnitVectorInView(view).dx * ((halfPi - touch.altitudeAngle) / halfPi) 200 | contrast = 1 + touch.azimuthUnitVectorInView(view).dy * -((halfPi - touch.altitudeAngle) / halfPi) 201 | 202 | case .GammaExposure: 203 | gamma = 1 + touch.azimuthUnitVectorInView(view).dx * ((halfPi - touch.altitudeAngle) / halfPi) 204 | exposure = touch.azimuthUnitVectorInView(view).dy * -((halfPi - touch.altitudeAngle) / halfPi) 205 | 206 | case .Off: 207 | () 208 | } 209 | 210 | updateLabel() 211 | applyFilter() 212 | } 213 | 214 | 215 | 216 | func applyFilter() 217 | { 218 | hueAdjust.setValue(coreImage, 219 | forKey: kCIInputImageKey) 220 | hueAdjust.setValue(hueAngle, 221 | forKey: kCIInputAngleKey) 222 | 223 | colorControls.setValue(hueAdjust.valueForKey(kCIOutputImageKey) as! CIImage, 224 | forKey: kCIInputImageKey) 225 | colorControls.setValue(saturation, 226 | forKey: kCIInputSaturationKey) 227 | colorControls.setValue(brightness, 228 | forKey: kCIInputBrightnessKey) 229 | colorControls.setValue(contrast, 230 | forKey: kCIInputContrastKey) 231 | 232 | exposureAdjust.setValue(colorControls.valueForKey(kCIOutputImageKey) as! CIImage, 233 | forKey: kCIInputImageKey) 234 | exposureAdjust.setValue(exposure, 235 | forKey: kCIInputEVKey) 236 | 237 | gammaAdjust.setValue(exposureAdjust.valueForKey(kCIOutputImageKey) as! CIImage, 238 | forKey: kCIInputImageKey) 239 | gammaAdjust.setValue(gamma, 240 | forKey: "inputPower") 241 | 242 | 243 | let cgImage = ciContext.createCGImage(gammaAdjust.valueForKey(kCIOutputImageKey) as! CIImage, 244 | fromRect: coreImage.extent) 245 | 246 | imageView.image = UIImage(CGImage: cgImage) 247 | } 248 | 249 | func updateLabel() 250 | { 251 | switch filteringMode 252 | { 253 | case .HueSaturation: 254 | label.text = String(format: "↻Hue: %.2f°", hueAngle * 180 / pi) + " " + String(format: "∢Saturation: %.2f", saturation) 255 | 256 | case .BrightnessContrast: 257 | label.text = String(format: "⇔Brightness: %.2f", brightness) + " " + String(format: "⇕Contrast: %.2f", contrast) 258 | 259 | case .GammaExposure: 260 | label.text = String(format: "⇔Gamma: %.2f", gamma) + " " + String(format: "⇕Exposure: %.2f", exposure) 261 | 262 | case .Off: 263 | () 264 | } 265 | } 266 | 267 | func addLights() 268 | { 269 | // ambient light... 270 | 271 | let ambientLight = SCNLight() 272 | ambientLight.type = SCNLightTypeAmbient 273 | ambientLight.color = UIColor(white: 0.15, alpha: 1.0) 274 | let ambientLightNode = SCNNode() 275 | ambientLightNode.light = ambientLight 276 | 277 | scene.rootNode.addChildNode(ambientLightNode) 278 | 279 | // omni light... 280 | 281 | let omniLight = SCNLight() 282 | omniLight.type = SCNLightTypeOmni 283 | omniLight.color = UIColor(white: 1.0, alpha: 1.0) 284 | let omniLightNode = SCNNode() 285 | omniLightNode.light = omniLight 286 | omniLightNode.position = SCNVector3(x: -10, y: 10, z: 30) 287 | 288 | scene.rootNode.addChildNode(omniLightNode) 289 | } 290 | 291 | override func viewDidLayoutSubviews() 292 | { 293 | label.frame = CGRect(x: 0, 294 | y: topLayoutGuide.length, 295 | width: view.frame.width, 296 | height: label.intrinsicContentSize().height) 297 | 298 | imageView.frame = view.bounds 299 | sceneKitView.frame = view.bounds 300 | 301 | // Slightly cobbled together layout :) 302 | 303 | hueSaturationButton.frame = CGRect(x: 0, 304 | y: view.frame.height - hueSaturationButton.intrinsicContentSize().height, 305 | width: hueSaturationButton.intrinsicContentSize().width, 306 | height: hueSaturationButton.intrinsicContentSize().height) 307 | 308 | brightnessContrastButton.frame = CGRect(x: hueSaturationButton.intrinsicContentSize().width + 20, 309 | y: view.frame.height - hueSaturationButton.intrinsicContentSize().height, 310 | width: hueSaturationButton.intrinsicContentSize().width, 311 | height: hueSaturationButton.intrinsicContentSize().height) 312 | 313 | gammaExposureButton.frame = CGRect(x: hueSaturationButton.intrinsicContentSize().width + 20 + hueSaturationButton.intrinsicContentSize().width + 20, 314 | y: view.frame.height - hueSaturationButton.intrinsicContentSize().height, 315 | width: hueSaturationButton.intrinsicContentSize().width, 316 | height: hueSaturationButton.intrinsicContentSize().height) 317 | } 318 | 319 | } 320 | 321 | enum FilteringMode 322 | { 323 | case Off 324 | case HueSaturation 325 | case BrightnessContrast 326 | case GammaExposure 327 | } 328 | 329 | class ChunkyButton: UIButton 330 | { 331 | let defaultColor = UIColor(red: 0.25, green: 0.25, blue: 0.75, alpha: 0.5) 332 | let highlightedColor = UIColor(red: 0.25, green: 0.25, blue: 0.75, alpha: 1) 333 | 334 | let filteringMode: FilteringMode 335 | 336 | required init(title: String, filteringMode: FilteringMode) 337 | { 338 | self.filteringMode = filteringMode 339 | 340 | super.init(frame: CGRectZero) 341 | 342 | titleLabel?.numberOfLines = 2 343 | setTitle(title, forState: UIControlState.Normal) 344 | titleLabel?.font = UIFont.boldSystemFontOfSize(24) 345 | 346 | backgroundColor = defaultColor 347 | setTitleColor(UIColor.whiteColor(), forState: UIControlState.Highlighted) 348 | setTitleColor(UIColor.lightGrayColor(), forState: UIControlState.Normal) 349 | 350 | layer.borderColor = UIColor.whiteColor().CGColor 351 | layer.borderWidth = 2 352 | layer.cornerRadius = 5 353 | } 354 | 355 | override var highlighted: Bool 356 | { 357 | didSet 358 | { 359 | backgroundColor = highlighted ? highlightedColor : defaultColor 360 | } 361 | } 362 | 363 | required init?(coder aDecoder: NSCoder) 364 | { 365 | fatalError("init(coder:) has not been implemented") 366 | } 367 | 368 | override func intrinsicContentSize() -> CGSize 369 | { 370 | return CGSize(width: super.intrinsicContentSize().width + 20, 371 | height: super.intrinsicContentSize().height + 10) 372 | } 373 | } 374 | 375 | --------------------------------------------------------------------------------