feat: Update for offscreen canvas and retool for cleaner CPU kernel backend

fix toString for kernels as well
Added documentation
Updated release year

Author: robertleeplummerjr

LICENSE

@@ -1,6 +1,6 @@
 The MIT License
 
-Copyright (c) 2017 gpu.js Team
+Copyright (c) 2018 gpu.js Team
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,16 +1,16 @@
 [![Logo](http://gpu.rocks/img/ogimage.png)](http://gpu.rocks/)
 
 
-# gpu.js
-gpu.js is a JavaScript Acceleration library for GPGPU (General purpose computing on GPUs) in JavaScript. gpu.js will automatically compile simple JavaScript functions into shader language and run them on the GPU. In case a GPU is not available, the functions will still run in regular JavaScript.
+# GPU.js
+GPU.js is a JavaScript Acceleration library for GPGPU (General purpose computing on GPUs) in JavaScript. GPU.js will automatically compile simple JavaScript functions into shader language and run them on the GPU. In case a GPU is not available, the functions will still run in regular JavaScript.
 
 
 [![Join the chat at https://gitter.im/gpujs/gpu.js](https://badges.gitter.im/gpujs/gpu.js.svg)](https://gitter.im/gpujs/gpu.js?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![Slack](https://slack.bri.im/badge.svg)](https://slack.bri.im)
 
 # What is this sorcery?
 
-Matrix multiplication written in gpu.js:
+Matrix multiplication written in GPU.js:
 
 ```js
 const gpu = new GPU();
@@ -50,6 +50,7 @@ Or alternatively you can experiment around with the [kernel playground here](htt
 * [Adding Custom Functions Directly to Kernel](#adding-custom-functions-directly-to-kernel)
 * [Loops](#loops)
 * [Pipelining](#pipelining)
+* [Offscreen Canvas](#offscreen-canvas)
 * [Cleanup](#cleanup)
 * [Flattened typed array support](#flattened-typed-array-support)
 * [Supported Math functions](#supported-math-functions)
@@ -78,7 +79,7 @@ yarn add gpu.js
 
 ### Browser
 
-Download the latest version of gpu.js and include the files in your HTML page using the following tags:
+Download the latest version of GPU.js and include the files in your HTML page using the following tags:
 
 ```html
 <script src="/path/to/js/gpu.min.js"></script>
@@ -405,12 +406,46 @@ const matMult = gpu.createKernel(function(a, b) {
 [Pipeline](https://en.wikipedia.org/wiki/Pipeline_(computing)) is a feature where values are sent directly from kernel to kernel via a texture.
 This results in extremely fast computing.  This is achieved with the kernel option `outputToTexture: boolean` option or by calling `kernel.setOutputToTexture(true)`
 
+## Offscreen Canvas
+GPU.js supports offscreen canvas where available.  Here is an example of how to use it with two files, `gpu-worker.js`, and `index.js`:
+
+file: `gpu-worker.js`
+```js
+importScripts('path/to/gpu.js');
+onmessage = function() {
+  // define gpu instance
+  const gpu = new GPU();
+  
+  // input values
+  const a = [1,2,3];
+  const b = [3,2,1];
+  
+  // setup kernel
+  const kernel = gpu.createKernel(function(a, b) {
+    return a[this.thread.x] - b[this.thread.x];
+  })
+    .setOutput([3]);
+  
+  // output some results!
+  postMessage(kernel(a, b));
+};
+```
+
+file: `index.js`
+```js
+var worker = new Worker('gpu-worker.js');
+worker.onmessage = function(e) {
+  var result = e.data;
+  console.log(result);
+};
+```
+
 ## Cleanup
 * for instances of `GPU` use the `destroy` method.  Example: `gpu.destroy()`
 * for instances of `Kernel` use the `destroy` method.  Example: `kernel.destroy()`
 
 ## Flattened typed array support
-To use the useful `x`, `y`, `z` `thread` lookup api inside of gpu.js, and yet use flattened arrays, there is the `Input` type.
+To use the useful `x`, `y`, `z` `thread` lookup api inside of GPU.js, and yet use flattened arrays, there is the `Input` type.
 This is generally much faster for when sending values to the gpu, especially with larger data sets.  Usage example:
 ```js
 import GPU, { input } from 'gpu.js';
@@ -490,7 +525,7 @@ We promise never to pass off your code as ours.
 
 The MIT License
 
-Copyright (c) 2017 gpu.js Team
+Copyright (c) 2018 GPU.js Team
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

bin/gpu-core.js

@@ -4,8 +4,8 @@
  *
  * GPU Accelerated JavaScript
  *
- * @version 1.8.1
- * @date Fri Sep 21 2018 06:53:44 GMT-0400 (EDT)
+ * @version 1.9.0
+ * @date Wed Oct 24 2018 14:09:46 GMT-0400 (EDT)
  *
  * @license MIT
  * The MIT License
@@ -88,7 +88,7 @@ var UtilsCore = function () {
 
 
 		value: function isCanvas(canvasObj) {
-			return canvasObj !== null && canvasObj.nodeName && canvasObj.getContext && canvasObj.nodeName.toUpperCase() === 'CANVAS';
+			return canvasObj !== null && (canvasObj.nodeName && canvasObj.getContext && canvasObj.nodeName.toUpperCase() === 'CANVAS' || typeof OffscreenCanvas !== 'undefined' && canvasObj instanceof OffscreenCanvas);
 		}
 
 
@@ -106,7 +106,7 @@ var UtilsCore = function () {
 				return null;
 			}
 
-			var canvas = document.createElement('canvas');
+			var canvas = typeof document !== 'undefined' ? document.createElement('canvas') : new OffscreenCanvas(0, 0);
 
 			canvas.width = 2;
 			canvas.height = 2;
@@ -124,11 +124,25 @@ var UtilsCore = function () {
 		}
 
 
+	}, {
+		key: 'isWebGl2',
+		value: function isWebGl2(webGl2Obj) {
+			return webGl2Obj && typeof WebGL2RenderingContext !== 'undefined' && webGl2Obj instanceof WebGL2RenderingContext;
+		}
+
+
 	}, {
 		key: 'isWebGlSupported',
 		value: function isWebGlSupported() {
 			return _isWebGlSupported;
 		}
+
+
+	}, {
+		key: 'isWebGl2Supported',
+		value: function isWebGl2Supported() {
+			return _isWebGl2Supported;
+		}
 	}, {
 		key: 'isWebGlDrawBuffersSupported',
 		value: function isWebGlDrawBuffersSupported() {
@@ -161,7 +175,16 @@ var UtilsCore = function () {
 				throw new Error('Invalid canvas object - ' + canvasObj);
 			}
 
-			var webGl = canvasObj.getContext('experimental-webgl', UtilsCore.initWebGlDefaultOptions()) || canvasObj.getContext('webgl', UtilsCore.initWebGlDefaultOptions());
+			var webGl = null;
+			var defaultOptions = UtilsCore.initWebGlDefaultOptions();
+			try {
+				webGl = canvasObj.getContext('experimental-webgl', defaultOptions);
+			} catch (e) {
+			}
+
+			if (webGl === null) {
+				webGl = canvasObj.getContext('webgl2', defaultOptions) || canvasObj.getContext('webgl', defaultOptions);
+			}
 
 			if (webGl) {
 				webGl.OES_texture_float = webGl.getExtension('OES_texture_float');
@@ -194,6 +217,7 @@ var UtilsCore = function () {
 	}, {
 		key: 'checkOutput',
 		value: function checkOutput(output) {
+			if (!output || !Array.isArray(output)) throw new Error('kernel.output not an array');
 			for (var i = 0; i < output.length; i++) {
 				if (isNaN(output[i]) || output[i] < 1) {
 					throw new Error('kernel.output[' + i + '] incorrectly defined as `' + output[i] + '`, needs to be numeric, and greater than 0');
@@ -206,9 +230,11 @@ var UtilsCore = function () {
 }();
 
 
-var _isCanvasSupported = typeof document !== 'undefined' ? UtilsCore.isCanvas(document.createElement('canvas')) : false;
+var _isCanvasSupported = typeof document !== 'undefined' ? UtilsCore.isCanvas(document.createElement('canvas')) : typeof OffscreenCanvas !== 'undefined';
 var _testingWebGl = UtilsCore.initWebGl(UtilsCore.initCanvas());
+var _testingWebGl2 = UtilsCore.initWebGl2(UtilsCore.initCanvas());
 var _isWebGlSupported = UtilsCore.isWebGl(_testingWebGl);
+var _isWebGl2Supported = UtilsCore.isWebGl2(_testingWebGl2);
 var _isWebGlDrawBuffersSupported = _isWebGlSupported && Boolean(_testingWebGl.getExtension('WEBGL_draw_buffers'));
 
 if (_isWebGlSupported) {