This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).
Matrix multiplication is a mathematical operation that defines the product of
| Device | OS | OS version | Browser | Browser version | WebGL | WebGL2 |
|---|---|---|---|---|---|---|
| Apple iPad 5th | iOS | 11.0.3 | Mobile Safari | 11.0 | X | |
| Apple iPad Air 2 | iOS | 8.4 | Mobile Safari | 8.0 | X | |
| Apple iPad Mini 3 | iOS | 8.1.2 | Mobile Safari | 8.0 | X | |
| Apple iPad Pro | iOS | 11.2.1 | Mobile Safari | 11.0 | X | |
| Apple iPhone 5S | iOS | 8.1.3 | Mobile Safari | 8.0 | X | |
| Apple iPhone 6 Plus | iOS | 8.1 | Mobile Safari | 8.0 | X | |
| Apple iPhone 6 | iOS | 8.1.3 | Mobile Safari | 8.0 | X | |
| Apple iPhone 6S Plus | iOS | 9.0.1 | Mobile Safari | 9.0 | X |
| // run with : | |
| // node --trace_deopt --allow-natives-syntax FILENAME | |
| function adder(a, b) { | |
| return new Function('a', 'b', 'return b%2 ? a + b : b%3 ? a - b : b%5 ? b / a : a * b')(a, b); | |
| } | |
| function addereval(a, b) { | |
| return eval('b%2 ? a + b : b%3 ? a - b : b%5 ? b / a : a * b'); | |
| } |
Some quick thoughts on https://twitter.com/dan_abramov/status/884892244817346560. It's not ignorant at all to ask how browser vendors approach performance. On the V8 side we've discussed bytecode precompilation challenges a few times this year. Here's my recollection of where we stand on the idea:
JavaScript engines like V8 have to work on multiple architectures. Every version of V8 is different. The architectures we target are different. A precompiled bytecode solution would require a system (e.g the server or a CDN) to generate bytecode builds for every target architecture, every version of V8 supported and every version of the JavaScript libraries or bundles bytecode is being generated for. This is because we would need to make sure every user accessing a page using that bytecode can still get the final JS successfully executed.
Consider that if a cross-browser solution to this problem was desired, the above would need to be applied to JavaScriptCore, SpiderMonkey and Chakra as well. It would need to ca
| const resize = () => { | |
| let | |
| w = window.innerWidth, | |
| h = window.innerHeight, | |
| l, t | |
| // 横屏 | |
| if (window.innerWidth / window.innerHeight >= 1) { | |
| view.style.transform = 'rotate(0)' | |
| window.GAME_ROTATE = 0 | |
| if (window.innerWidth / window.innerHeight >= GAME_RATIO) { |
A non-exhaustive list of WebGL and WebGPU frameworks and libraries. It is mostly for learning purposes as some of the libraries listed are wip/outdated/not maintained anymore.
| Name | Stars | Last Commit | Description |
|---|---|---|---|
| three.js | 
| SAFARI 10.0.1 | |
| Mozilla/5.0 (iPhone; CPU iPhone OS 10_0_1 like Mac OS X) AppleWebKit/602.1.50 (KHTML, like Gecko) Version/10.0 Mobile/14A403 Safari/602.1 | |
| CHROME on 10.0.1 | |
| Mozilla/5.0 (iPhone; CPU iPhone OS 10_0_1 like Mac OS X) AppleWebKit/601.1 (KHTML, like Gecko) CriOS/53.0.2785.86 Mobile/14A403 Safari/601.1.46 | |
| FACEBOOK MESSENGER | |
| Mozilla/5.0 (iPhone; CPU iPhone OS 10_0_1 like Mac OS X) AppleWebKit/602.1.50 (KHTML, like Gecko) Mobile/14A403 [FBAN/MessengerForiOS;FBAV/87.0.0.24.69;FBBV/38293694;FBRV/0;FBDV/iPhone8,4;FBMD/iPhone;FBSN/iPhone OS;FBSV/10.0.1;FBSS/2;FBCR/AT&T;FBID/phone;FBLC/en_US;FBOP/5] | |
| TWITTER FOR IPHONE |
Disclaimer: Please follow this guide being aware of the fact that I'm not an expert regarding the things outlined below, however I made my best attempt. A few people in IRC confirmed it worked for them and the results looked acceptable.
Attention: After following all the steps run gdk-pixbuf-query-loaders --update-cache as root, this prevents various gdk-related bugs that have been reported in the last few hours. Symptoms are varied, and for Cinnamon the DE fails to start entirely while for XFCE the icon theme seemingly can't be changed anymore etc.
Check the gist's comments for any further tips and instructions, especially if you are running into problems!
Results after following the guide as of 11.01.2017 13:08:
| const pixi = require('pixi.js'); | |
| const three = require('three'); | |
| // Create the pixi.js renderer | |
| const pixiRenderer = pixi.autoDetectRenderer(512, 512, { transparent: true }); | |
| // Create the three.js renderer | |
| const threeRenderer = new three.WebGLRenderer(); | |
| threeRenderer.setSize(window.innerWidth, window.innerHeight); | |
| threeRenderer.autoClear = false; |
| /* | |
| * edtaa3() | |
| * | |
| * Sweep-and-update Euclidean distance transform of an | |
| * image. Positive pixels are treated as object pixels, | |
| * zero or negative pixels are treated as background. | |
| * An attempt is made to treat antialiased edges correctly. | |
| * The input image must have pixels in the range [0,1], | |
| * and the antialiased image should be a box-filter | |
| * sampling of the ideal, crisp edge. |
