├── CONTRIBUTING.md ├── README.md └── LICENSE /CONTRIBUTING.md: -------------------------------------------------------------------------------- 1 | # How to Contribute 2 | 3 | We'd love to accept your patches and contributions to this project. There are 4 | just a few small guidelines you need to follow. 5 | 6 | ## Contributor License Agreement 7 | 8 | Contributions to this project must be accompanied by a Contributor License 9 | Agreement. You (or your employer) retain the copyright to your contribution, 10 | this simply gives us permission to use and redistribute your contributions as 11 | part of the project. Head over to to see 12 | your current agreements on file or to sign a new one. 13 | 14 | You generally only need to submit a CLA once, so if you've already submitted one 15 | (even if it was for a different project), you probably don't need to do it 16 | again. 17 | 18 | ## Code reviews 19 | 20 | All submissions, including submissions by project members, require review. We 21 | use GitHub pull requests for this purpose. Consult 22 | [GitHub Help](https://help.github.com/articles/about-pull-requests/) for more 23 | information on using pull requests. 24 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Open Mini Games Format 2 | 3 | The Open Mini Games (OMG) format is a proposal to define a set of combined minimum requirements that game developers can implement when developing a game that is playable in a web browser or a client which renders HTML5 content. 4 | 5 | The aim of the requirements is to provide the information necessary to surface a web game in a standardized manner on discovery platforms such as browsers but also embedded platforms. 6 | 7 | In theory, the combination of these requirements will enable catalogs of web games to be collected, filtered and surfaced to end users. 8 | 9 | The final representations of the games should be meaningingful concise to end users and showcase the games in a manner that users have become familiar with when browsing general game catalog interfaces - such as Steam, Google Play or the Apple App Store. 10 | 11 | ## User Experience Goals 12 | 13 | The goal of each piece of metadata is to unlock a feature or improvement towards one of the following areas: 14 | - Discovery 15 | - Rediscovery 16 | - Installability 17 | - Load Time 18 | - Offline Access 19 | 20 | Different platforms which wish to surface HTML5 game content can leverage these metadata towards the above goals. Ideally each piece of metadata should be useful in its own right. When combined, they aim to reduce friction and enable new capabilities for game platforms. 21 | 22 | ## Requirements 23 | 24 | An HTML document that is also a playable web game must have the following three pieces of metadata included on its page: 25 | - VideoGame Schema Markup with additional constraints. 26 | - Progressive Web App Manifest. 27 | - OMG Resources Manifest: A list of the resources necessary for offline play or initial precaching. 28 | 29 | To be a completely valid OMG, a webpage must include all 3 pieces of metadata. However, surfacing platforms can leverage individual pieces of metadata for their specific use cases. 30 | 31 | ### VideoGame Schema Markup for Web Games 32 | 33 | #### Explainer 34 | 35 | The VideoGame Schema Markup (with web game property constraints) provides a surfacing platform with the information necessary to describe the game effectively as a search result or a featured item on a store page. Theoretically, a surfacing platform could also provide users with a “recently played” user journey in which users could quickly jump back into their most recently played web games based on the existence of the games in the user’s browser or navigation history. This metadata helps with ‘Discovery’ and ‘Rediscovery’ of content. 36 | 37 | #### Example 38 | 39 | In index.html within HEAD tag: 40 | 41 | ~~~html 42 | 43 | 85 | ... 86 | ~~~ 87 | 88 | Relevant docs: 89 | https://schema.org/VideoGame 90 | 91 | #### Additional constraints: 92 | - “genre" must be written in lowercase, and be one or two of the following predefined genres. To represent two genres, use a pipe character, for example “arcade|racing": 93 | - Action 94 | - Arcade 95 | - RPG 96 | - Adventure 97 | - Board 98 | - Card 99 | - Family 100 | - Music 101 | - Educational 102 | - Racing 103 | - Simulation 104 | - Strategy 105 | - Trivia 106 | - Word 107 | - “operatingSystem" must be “web" 108 | - “icon" must refer to an image in either PNG, JPG or WEBP format with a minimum width of 1024 pixels, a minimum height of 1024 pixels and a 1:1 aspect ratio. 109 | - “gameBanner" must refer to an image in either PNG, JPG or WEBP format with a minimum height of 1024 pixels and an aspect ratio of 4:3 110 | - “accessibilityControl" must be written in lowercase, and be one 111 | - “gameExecutionMode” must be written in lowercase and be either ‘clientside’ or ‘serverside’. ‘clientside’ refers to games that execute their game code in JavaScript on the client. ‘serverside’ refers to games that execute their game code on a remote server and stream their graphics and audio to the client. 112 | 113 | ### Progressive Web App Manifest 114 | 115 | #### Explainer 116 | 117 | The Progressive Web App Manifest is already used by platforms such as Android to enable web applications and web games to be installed to the device and easily launched via the Android home screen. This metadata serves as a form of ‘Rediscovery’ and ‘Installability’. 118 | 119 | #### Example 120 | 121 | In index.html within HEAD tag: 122 | 123 | ~~~html 124 | 125 | 126 | ... 127 | ~~~ 128 | 129 | Example manifest.webmanifest: 130 | 131 | ~~~json 132 | { 133 | "name": "Game title", 134 | "short_name": "Game title", 135 | "start_url": ".", 136 | "display": "standalone", 137 | "background_color": "#fff", 138 | "description": "Game description", 139 | "icons": [{ 140 | "src": "images/touch/homescreen48.png", 141 | "sizes": "48x48", 142 | "type": "image/png" 143 | }, { 144 | "src": "images/touch/homescreen72.png", 145 | "sizes": "72x72", 146 | "type": "image/png" 147 | }, { 148 | "src": "images/touch/homescreen96.png", 149 | "sizes": "96x96", 150 | "type": "image/png" 151 | }, { 152 | "src": "images/touch/homescreen144.png", 153 | "sizes": "144x144", 154 | "type": "image/png" 155 | }, { 156 | "src": "images/touch/homescreen168.png", 157 | "sizes": "168x168", 158 | "type": "image/png" 159 | }, { 160 | "src": "images/touch/homescreen192.png", 161 | "sizes": "192x192", 162 | "type": "image/png" 163 | }], 164 | "related_applications": [{ 165 | "platform": "play", 166 | "url": "https://play.google.com/store/apps/details?id=cheeaun.hackerweb" 167 | }] 168 | } 169 | ~~~ 170 | 171 | Relevant docs: 172 | https://developer.mozilla.org/en-US/docs/Web/Manifest 173 | 174 | #### Additional constraints: 175 | - If an OMG implements both the VideoGame Schema Markup and the PWA manifest, then the icon property of the VideoGame Schema Markup must match one of the URLs of the PWA manifest icons array. 176 | 177 | ### OMG Resources Manifest 178 | 179 | #### Explainer 180 | 181 | The Web Bundle Resources Manifest provides an explicit list of all the resources necessary for a web game to be played offline. Extending this proposal is the OMG Resources Manifest which can be referenced as a separate file from a webpage's meta data to indicate that it is ready for offline bundling. This would communicate that the game can be bundled with a set of resources for playing offline or that resources servce as an ideal set that could be precached to improve load times. 182 | 183 | Enables surfacing platforms and clients to pre-cache resources of games discovered on the open web for offline playback or improved loading times. This metadata assists with ‘Load Time’ and ‘Offline Access’. 184 | 185 | #### Example 186 | 187 | In index.html within HEAD tag: 188 | 189 | ~~~html 190 | 191 | 192 | ... 193 | ~~~ 194 | 195 | If this bundle of files enables a web game to be completely playable offline then the optional flag “offline-capable” property can be included. If the “offline-capable” property is not included, the surfacing platform should assume these files are merely recommended for the purpose of precaching. 196 | 197 | Example files.txt: 198 | 199 | ~~~bash 200 | # A line starting with '#' is a comment. 201 | https://example.com/ 202 | https://example.com/manifest.webmanifest 203 | https://example.com/style.css 204 | https://example.com/script.js 205 | ~~~ 206 | 207 | Relevant docs: 208 | https://github.com/WICG/webpackage/tree/master/go/bundle#from-a-url-list 209 | 210 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | 2 | Apache License 3 | Version 2.0, January 2004 4 | http://www.apache.org/licenses/ 5 | 6 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 7 | 8 | 1. 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