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WebGL-2d HSL Fix
<h3>Canvas2D</h3>
<canvas id="canvas-default"></canvas>
<h3>Webgl-2d</h3>
<canvas id="canvas-webgl"></canvas>
<script src="webgl-2d.js"></script>
<script>
var width = 600,
height = 200;
var canvasDefault = document.getElementById("canvas-default");
canvasDefault.width = width;
canvasDefault.height = height;
var canvasWebgl = document.getElementById("canvas-webgl");
canvasWebgl.width = width;
canvasWebgl.height = height;
WebGL2D.enable(canvasWebgl)
var ctx = canvasDefault.getContext("2d");
var webgl = canvasWebgl.getContext("webgl-2d");
var j = 10;
while (--j > 0) {
var i = 20;
while (--i > 0) {
var color = "hsl(" + (360/i) + "," + (100/j) + "%,50%)";
ctx.fillStyle = color;
webgl.fillStyle = color;
ctx.fillRect(30*(i-1),20*(j-1),20,15);
webgl.fillRect(30*(i-1),20*(j-1),20,15);
}
}
</script>
/**
* WebGL-2D.js - HTML5 Canvas2D API in a WebGL context
*
* Created by Corban Brook <corbanbrook@gmail.com> on 2011-03-02.
* Amended to by Bobby Richter <secretrobotron@gmail.com> on 2011-03-03
* CubicVR.js by Charles Cliffe <cj@cubicproductions.com> on 2011-03-03
*
*/
/*
* Copyright (c) 2011 Corban Brook
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
/**
* Usage:
*
* var cvs = document.getElementById("myCanvas");
*
* WebGL2D.enable(cvs); // adds "webgl-2d" to cvs
*
* cvs.getContext("webgl-2d");
*
*/
(function(Math, undefined) {
// Vector & Matrix libraries from CubicVR.js
var M_PI = 3.1415926535897932384626433832795028841968;
var M_TWO_PI = 2.0 * M_PI;
var M_HALF_PI = M_PI / 2.0;
function isPOT(value) {
return value > 0 && ((value - 1) & value) === 0;
}
var vec3 = {
length: function(pt) {
return Math.sqrt(pt[0] * pt[0] + pt[1] * pt[1] + pt[2] * pt[2]);
},
normalize: function(pt) {
var d = Math.sqrt((pt[0] * pt[0]) + (pt[1] * pt[1]) + (pt[2] * pt[2]));
if (d === 0) {
return [0, 0, 0];
}
return [pt[0] / d, pt[1] / d, pt[2] / d];
},
dot: function(v1, v2) {
return v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2];
},
angle: function(v1, v2) {
return Math.acos((v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2]) / (Math.sqrt(v1[0] * v1[0] + v1[1] * v1[1] + v1[2] * v1[2]) * Math.sqrt(v2[0] * v2[0] + v2[1] * v2[1] + v2[2] * v2[2])));
},
cross: function(vectA, vectB) {
return [vectA[1] * vectB[2] - vectB[1] * vectA[2], vectA[2] * vectB[0] - vectB[2] * vectA[0], vectA[0] * vectB[1] - vectB[0] * vectA[1]];
},
multiply: function(vectA, constB) {
return [vectA[0] * constB, vectA[1] * constB, vectA[2] * constB];
},
add: function(vectA, vectB) {
return [vectA[0] + vectB[0], vectA[1] + vectB[1], vectA[2] + vectB[2]];
},
subtract: function(vectA, vectB) {
return [vectA[0] - vectB[0], vectA[1] - vectB[1], vectA[2] - vectB[2]];
},
equal: function(a, b) {
var epsilon = 0.0000001;
if ((a === undefined) && (b === undefined)) {
return true;
}
if ((a === undefined) || (b === undefined)) {
return false;
}
return (Math.abs(a[0] - b[0]) < epsilon && Math.abs(a[1] - b[1]) < epsilon && Math.abs(a[2] - b[2]) < epsilon);
}
};
var mat3 = {
identity: [1.0, 0.0, 0.0,
0.0, 1.0, 0.0,
0.0, 0.0, 1.0],
multiply: function (m1, m2) {
var m10 = m1[0], m11 = m1[1], m12 = m1[2], m13 = m1[3], m14 = m1[4], m15 = m1[5], m16 = m1[6], m17 = m1[7], m18 = m1[8],
m20 = m2[0], m21 = m2[1], m22 = m2[2], m23 = m2[3], m24 = m2[4], m25 = m2[5], m26 = m2[6], m27 = m2[7], m28 = m2[8];
m2[0] = m20 * m10 + m23 * m11 + m26 * m12;
m2[1] = m21 * m10 + m24 * m11 + m27 * m12;
m2[2] = m22 * m10 + m25 * m11 + m28 * m12;
m2[3] = m20 * m13 + m23 * m14 + m26 * m15;
m2[4] = m21 * m13 + m24 * m14 + m27 * m15;
m2[5] = m22 * m13 + m25 * m14 + m28 * m15;
m2[6] = m20 * m16 + m23 * m17 + m26 * m18;
m2[7] = m21 * m16 + m24 * m17 + m27 * m18;
m2[8] = m22 * m16 + m25 * m17 + m28 * m18;
},
vec2_multiply: function (m1, m2) {
var mOut = [];
mOut[0] = m2[0] * m1[0] + m2[3] * m1[1] + m2[6];
mOut[1] = m2[1] * m1[0] + m2[4] * m1[1] + m2[7];
return mOut;
},
transpose: function (m) {
return [m[0], m[3], m[6], m[1], m[4], m[7], m[2], m[5], m[8]];
}
}; //mat3
// Transform library from CubicVR.js
function Transform(mat) {
return this.clearStack(mat);
}
var STACK_DEPTH_LIMIT = 16;
Transform.prototype.clearStack = function(init_mat) {
this.m_stack = [];
this.m_cache = [];
this.c_stack = 0;
this.valid = 0;
this.result = null;
for (var i = 0; i < STACK_DEPTH_LIMIT; i++) {
this.m_stack[i] = this.getIdentity();
}
if (init_mat !== undefined) {
this.m_stack[0] = init_mat;
} else {
this.setIdentity();
}
}; //clearStack
Transform.prototype.setIdentity = function() {
this.m_stack[this.c_stack] = this.getIdentity();
if (this.valid === this.c_stack && this.c_stack) {
this.valid--;
}
};
Transform.prototype.getIdentity = function() {
return [1.0, 0.0, 0.0,
0.0, 1.0, 0.0,
0.0, 0.0, 1.0];
};
Transform.prototype.getResult = function() {
if (!this.c_stack) {
return this.m_stack[0];
}
var m = mat3.identity;
if (this.valid > this.c_stack-1) { this.valid = this.c_stack-1; }
for (var i = this.valid; i < this.c_stack+1; i++) {
m = mat3.multiply(this.m_stack[i],m);
this.m_cache[i] = m;
}
this.valid = this.c_stack-1;
this.result = this.m_cache[this.c_stack];
return this.result;
};
Transform.prototype.pushMatrix = function() {
this.c_stack++;
this.m_stack[this.c_stack] = this.getIdentity();
};
Transform.prototype.popMatrix = function() {
if (this.c_stack === 0) { return; }
this.c_stack--;
};
var translateMatrix = Transform.prototype.getIdentity();
Transform.prototype.translate = function(x, y) {
translateMatrix[6] = x;
translateMatrix[7] = y;
mat3.multiply(translateMatrix, this.m_stack[this.c_stack]);
/*
if (this.valid === this.c_stack && this.c_stack) {
this.valid--;
}
*/
};
var scaleMatrix = Transform.prototype.getIdentity();
Transform.prototype.scale = function(x, y) {
scaleMatrix[0] = x;
scaleMatrix[4] = y;
mat3.multiply(scaleMatrix, this.m_stack[this.c_stack]);
/*
if (this.valid === this.c_stack && this.c_stack) {
this.valid--;
}
*/
};
var rotateMatrix = Transform.prototype.getIdentity();
Transform.prototype.rotate = function(ang) {
var sAng, cAng;
sAng = Math.sin(-ang);
cAng = Math.cos(-ang);
rotateMatrix[0] = cAng;
rotateMatrix[3] = sAng;
rotateMatrix[1] = -sAng;
rotateMatrix[4] = cAng;
mat3.multiply(rotateMatrix, this.m_stack[this.c_stack]);
/*
if (this.valid === this.c_stack && this.c_stack) {
this.valid--;
}
*/
};
var WebGL2D = this.WebGL2D = function WebGL2D(canvas, options) {
this.canvas = canvas;
this.options = options || {};
this.gl = undefined;
this.fs = undefined;
this.vs = undefined;
this.shaderProgram = undefined;
this.transform = new Transform();
this.shaderPool = [];
this.maxTextureSize = undefined;
// Save a reference to the WebGL2D instance on the canvas object
canvas.gl2d = this;
// Store getContext function for later use
canvas.$getContext = canvas.getContext;
// Override getContext function with "webgl-2d" enabled version
canvas.getContext = (function(gl2d) {
return function(context) {
if ((gl2d.options.force || context === "webgl-2d") && !(canvas.width === 0 || canvas.height === 0)) {
if (gl2d.gl) { return gl2d.gl; }
var gl = gl2d.gl = gl2d.canvas.$getContext("experimental-webgl");
gl2d.initShaders();
gl2d.initBuffers();
// Append Canvas2D API features to the WebGL context
gl2d.initCanvas2DAPI();
gl.viewport(0, 0, gl2d.canvas.width, gl2d.canvas.height);
// Disables writing to dest-alpha
// gl.colorMask(1,1,1,0)
// Depth options
//gl.enable(gl.DEPTH_TEST);
//gl.depthFunc(gl.LEQUAL);
// Blending options
// See http://stackoverflow.com/questions/11521035/blending-with-html-background-in-webgl
gl.enable(gl.BLEND);
gl.blendFuncSeparate(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA, gl.ONE, gl.ONE_MINUS_SRC_ALPHA);
gl2d.maxTextureSize = gl.getParameter(gl.MAX_TEXTURE_SIZE);
return gl;
} else {
return gl2d.canvas.$getContext(context);
}
};
}(this));
this.postInit();
};
// Enables WebGL2D on your canvas
WebGL2D.enable = function(canvas, options) {
return canvas.gl2d || new WebGL2D(canvas, options);
};
// Shader Pool BitMasks, i.e. sMask = (shaderMask.texture+shaderMask.stroke)
var shaderMask = {
texture: 1,
crop: 2,
path: 4
};
// Fragment shader source
WebGL2D.prototype.getFragmentShaderSource = function getFragmentShaderSource(sMask) {
var fsSource = [
"#ifdef GL_ES",
"precision highp float;",
"#endif",
"#define hasTexture " + ((sMask&shaderMask.texture) ? "1" : "0"),
"#define hasCrop " + ((sMask&shaderMask.crop) ? "1" : "0"),
"varying vec4 vColor;",
"#if hasTexture",
"varying vec2 vTextureCoord;",
"uniform sampler2D uSampler;",
"#if hasCrop",
"uniform vec4 uCropSource;",
"#endif",
"#endif",
"void main(void) {",
"#if hasTexture",
"#if hasCrop",
"gl_FragColor = texture2D(uSampler, vec2(vTextureCoord.x * uCropSource.z, vTextureCoord.y * uCropSource.w) + uCropSource.xy);",
"#else",
"gl_FragColor = texture2D(uSampler, vTextureCoord);",
"#endif",
"#else",
"gl_FragColor = vColor;",
"#endif",
"}"
].join("\n");
return fsSource;
};
WebGL2D.prototype.getVertexShaderSource = function getVertexShaderSource(stackDepth,sMask) {
var w = 2 / this.canvas.width, h = -2 / this.canvas.height;
stackDepth = stackDepth || 1;
var vsSource = [
"#define hasTexture " + ((sMask&shaderMask.texture) ? "1" : "0"),
"attribute vec4 aVertexPosition;",
"#if hasTexture",
"varying vec2 vTextureCoord;",
"#endif",
"uniform vec4 uColor;",
"uniform mat3 uTransforms[" + stackDepth + "];",
"varying vec4 vColor;",
"const mat4 pMatrix = mat4(" + w + ",0,0,0, 0," + h + ",0,0, 0,0,1.0,1.0, -1.0,1.0,0,0);",
"mat3 crunchStack(void) {",
"mat3 result = uTransforms[0];",
"for (int i = 1; i < " + stackDepth + "; ++i) {",
"result = uTransforms[i] * result;",
"}",
"return result;",
"}",
"void main(void) {",
"vec3 position = crunchStack() * vec3(aVertexPosition.x, aVertexPosition.y, 1.0);",
"gl_Position = pMatrix * vec4(position, 1.0);",
"vColor = uColor;",
"#if hasTexture",
"vTextureCoord = aVertexPosition.zw;",
"#endif",
"}"
].join("\n");
return vsSource;
};
// Initialize fragment and vertex shaders
WebGL2D.prototype.initShaders = function initShaders(transformStackDepth,sMask) {
var gl = this.gl;
transformStackDepth = transformStackDepth || 1;
sMask = sMask || 0;
var storedShader = this.shaderPool[transformStackDepth];
if (!storedShader) { storedShader = this.shaderPool[transformStackDepth] = []; }
storedShader = storedShader[sMask];
if (storedShader) {
gl.useProgram(storedShader);
this.shaderProgram = storedShader;
return storedShader;
} else {
var fs = this.fs = gl.createShader(gl.FRAGMENT_SHADER);
gl.shaderSource(this.fs, this.getFragmentShaderSource(sMask));
gl.compileShader(this.fs);
if (!gl.getShaderParameter(this.fs, gl.COMPILE_STATUS)) {
throw "fragment shader error: "+gl.getShaderInfoLog(this.fs);
}
var vs = this.vs = gl.createShader(gl.VERTEX_SHADER);
gl.shaderSource(this.vs, this.getVertexShaderSource(transformStackDepth,sMask));
gl.compileShader(this.vs);
if (!gl.getShaderParameter(this.vs, gl.COMPILE_STATUS)) {
throw "vertex shader error: "+gl.getShaderInfoLog(this.vs);
}
var shaderProgram = this.shaderProgram = gl.createProgram();
shaderProgram.stackDepth = transformStackDepth;
gl.attachShader(shaderProgram, fs);
gl.attachShader(shaderProgram, vs);
gl.linkProgram(shaderProgram);
if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
throw "Could not initialise shaders.";
}
gl.useProgram(shaderProgram);
shaderProgram.vertexPositionAttribute = gl.getAttribLocation(shaderProgram, "aVertexPosition");
gl.enableVertexAttribArray(shaderProgram.vertexPositionAttribute);
shaderProgram.uColor = gl.getUniformLocation(shaderProgram, 'uColor');
shaderProgram.uSampler = gl.getUniformLocation(shaderProgram, 'uSampler');
shaderProgram.uCropSource = gl.getUniformLocation(shaderProgram, 'uCropSource');
shaderProgram.uTransforms = [];
for (var i=0; i<transformStackDepth; ++i) {
shaderProgram.uTransforms[i] = gl.getUniformLocation(shaderProgram, 'uTransforms[' + i + ']');
} //for
this.shaderPool[transformStackDepth][sMask] = shaderProgram;
return shaderProgram;
} //if
};
var rectVertexPositionBuffer;
var rectVertexColorBuffer;
var pathVertexPositionBuffer;
var pathVertexColorBuffer;
// 2D Vertices and Texture UV coords
var rectVerts = new Float32Array([
0,0, 0,0,
0,1, 0,1,
1,1, 1,1,
1,0, 1,0
]);
WebGL2D.prototype.initBuffers = function initBuffers() {
var gl = this.gl;
rectVertexPositionBuffer = gl.createBuffer();
rectVertexColorBuffer = gl.createBuffer();
pathVertexPositionBuffer = gl.createBuffer();
pathVertexColorBuffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, rectVertexPositionBuffer);
gl.bufferData(gl.ARRAY_BUFFER, rectVerts, gl.STATIC_DRAW);
};
// Maintains an array of all WebGL2D instances
WebGL2D.instances = [];
WebGL2D.prototype.postInit = function() {
WebGL2D.instances.push(this);
};
// Extends gl context with Canvas2D API
WebGL2D.prototype.initCanvas2DAPI = function initCanvas2DAPI() {
var gl2d = this,
gl = this.gl;
// Rendering Canvas for text fonts
var textCanvas = document.createElement("canvas");
textCanvas.width = gl2d.canvas.width;
textCanvas.height = gl2d.canvas.height;
var textCtx = textCanvas.getContext("2d");
var reRGBAColor = /^rgb(a)?\(\s*(-?[\d]+)(%)?\s*,\s*(-?[\d]+)(%)?\s*,\s*(-?[\d]+)(%)?\s*,?\s*(-?[\d\.]+)?\s*\)$/;
var reHSLAColor = /^hsl(a)?\(\s*(-?[\d\.]+)\s*,\s*(-?[\d\.]+)%\s*,\s*(-?[\d\.]+)%\s*,?\s*(-?[\d\.]+)?\s*\)$/;
var reHex6Color = /^#([0-9A-Fa-f]{6})$/;
var reHex3Color = /^#([0-9A-Fa-f])([0-9A-Fa-f])([0-9A-Fa-f])$/;
// http://axonflux.com/handy-rgb-to-hsl-and-rgb-to-hsv-color-model-c
function HSLAToRGBA(h, s, l, a) {
var r, g, b, p, q;
// Clamp and Normalize values
h = (((h % 360) + 360) % 360) / 360;
s = s > 100 ? 1 : s / 100;
s = s < 0 ? 0 : s;
l = l > 100 ? 1 : l / 100;
l = l < 0 ? 0 : l;
if(s == 0) {
r = g = b = l; // achromatic
} else {
function hue2rgb(p, q, t){
if(t < 0) t += 1;
if(t > 1) t -= 1;
if(t < 1/6) return p + (q - p) * 6 * t;
if(t < 1/2) return q;
if(t < 2/3) return p + (q - p) * (2/3 - t) * 6;
return p;
}
q = l < 0.5 ? l * (1 + s) : l + s - l * s;
p = 2 * l - q;
r = hue2rgb(p, q, h + 1/3);
g = hue2rgb(p, q, h);
b = hue2rgb(p, q, h - 1/3);
}
return [r, g, b, a];
}
// Converts rgb(a) color string to gl color vector
function colorStringToVec4(value) {
var result = [], match, channel, isPercent, hasAlpha, alphaChannel, sameType;
if ((match = reRGBAColor.exec(value))) {
hasAlpha = match[1], alphaChannel = parseFloat(match[8]);
if ((hasAlpha && isNaN(alphaChannel)) || (!hasAlpha && !isNaN(alphaChannel))) {
return false;
}
sameType = match[3];
for (var i = 2; i < 8; i+=2) {
channel = match[i], isPercent = match[i+1];
if (isPercent !== sameType) {
return false;
}
// Clamp and normalize values
if (isPercent) {
channel = channel > 100 ? 1 : channel / 100;
channel = channel < 0 ? 0 : channel;
} else {
channel = channel > 255 ? 1 : channel / 255;
channel = channel < 0 ? 0 : channel;
}
result.push(channel);
}
result.push(hasAlpha ? alphaChannel : 1.0);
} else if ((match = reHSLAColor.exec(value))) {
hasAlpha = match[1], alphaChannel = parseFloat(match[5]);
result = HSLAToRGBA(match[2], match[3], match[4], parseFloat(hasAlpha && alphaChannel ? alphaChannel : 1.0));
} else if ((match = reHex6Color.exec(value))) {
var colorInt = parseInt(match[1], 16);
result = [((colorInt & 0xFF0000) >> 16) / 255, ((colorInt & 0x00FF00) >> 8) / 255, (colorInt & 0x0000FF) / 255, 1.0];
} else if ((match = reHex3Color.exec(value))) {
var hexString = "#" + [match[1], match[1], match[2], match[2], match[3], match[3]].join("");
result = colorStringToVec4(hexString);
} else if (value.toLowerCase() in colorKeywords) {
result = colorStringToVec4(colorKeywords[value.toLowerCase()]);
} else if (value.toLowerCase() === "transparent") {
result = [0, 0, 0, 0];
} else {
// Color keywords not yet implemented, ie "orange", return hot pink
return false;
}
return result;
}
function colorVecToString(vec4) {
return "rgba(" + (vec4[0] * 255) + ", " + (vec4[1] * 255) + ", " + (vec4[2] * 255) + ", " + parseFloat(vec4[3]) + ")";
}
var colorKeywords = {
aliceblue: "#f0f8ff",
antiquewhite: "#faebd7",
aqua: "#00ffff",
aquamarine: "#7fffd4",
azure: "#f0ffff",
beige: "#f5f5dc",
bisque: "#ffe4c4",
black: "#000000",
blanchedalmond: "#ffebcd",
blue: "#0000ff",
blueviolet: "#8a2be2",
brown: "#a52a2a",
burlywood: "#deb887",
cadetblue: "#5f9ea0",
chartreuse: "#7fff00",
chocolate: "#d2691e",
coral: "#ff7f50",
cornflowerblue: "#6495ed",
cornsilk: "#fff8dc",
crimson: "#dc143c",
cyan: "#00ffff",
darkblue: "#00008b",
darkcyan: "#008b8b",
darkgoldenrod: "#b8860b",
darkgray: "#a9a9a9",
darkgreen: "#006400",
darkkhaki: "#bdb76b",
darkmagenta: "#8b008b",
darkolivegreen: "#556b2f",
darkorange: "#ff8c00",
darkorchid: "#9932cc",
darkred: "#8b0000",
darksalmon: "#e9967a",
darkseagreen: "#8fbc8f",
darkslateblue: "#483d8b",
darkslategray: "#2f4f4f",
darkturquoise: "#00ced1",
darkviolet: "#9400d3",
deeppink: "#ff1493",
deepskyblue: "#00bfff",
dimgray: "#696969",
dodgerblue: "#1e90ff",
firebrick: "#b22222",
floralwhite: "#fffaf0",
forestgreen: "#228b22",
fuchsia: "#ff00ff",
gainsboro: "#dcdcdc",
ghostwhite: "#f8f8ff",
gold: "#ffd700",
goldenrod: "#daa520",
gray: "#808080",
green: "#008000",
greenyellow: "#adff2f",
grey: "#808080",
honeydew: "#f0fff0",
hotpink: "#ff69b4",
indianred: "#cd5c5c",
indigo: "#4b0082",
ivory: "#fffff0",
khaki: "#f0e68c",
lavender: "#e6e6fa",
lavenderblush: "#fff0f5",
lawngreen: "#7cfc00",
lemonchiffon: "#fffacd",
lightblue: "#add8e6",
lightcoral: "#f08080",
lightcyan: "#e0ffff",
lightgoldenrodyellow: "#fafad2",
lightgrey: "#d3d3d3",
lightgreen: "#90ee90",
lightpink: "#ffb6c1",
lightsalmon: "#ffa07a",
lightseagreen: "#20b2aa",
lightskyblue: "#87cefa",
lightslategray: "#778899",
lightsteelblue: "#b0c4de",
lightyellow: "#ffffe0",
lime: "#00ff00",
limegreen: "#32cd32",
linen: "#faf0e6",
magenta: "#ff00ff",
maroon: "#800000",
mediumaquamarine: "#66cdaa",
mediumblue: "#0000cd",
mediumorchid: "#ba55d3",
mediumpurple: "#9370d8",
mediumseagreen: "#3cb371",
mediumslateblue: "#7b68ee",
mediumspringgreen: "#00fa9a",
mediumturquoise: "#48d1cc",
mediumvioletred: "#c71585",
midnightblue: "#191970",
mintcream: "#f5fffa",
mistyrose: "#ffe4e1",
moccasin: "#ffe4b5",
navajowhite: "#ffdead",
navy: "#000080",
oldlace: "#fdf5e6",
olive: "#808000",
olivedrab: "#6b8e23",
orange: "#ffa500",
orangered: "#ff4500",
orchid: "#da70d6",
palegoldenrod: "#eee8aa",
palegreen: "#98fb98",
paleturquoise: "#afeeee",
palevioletred: "#d87093",
papayawhip: "#ffefd5",
peachpuff: "#ffdab9",
peru: "#cd853f",
pink: "#ffc0cb",
plum: "#dda0dd",
powderblue: "#b0e0e6",
purple: "#800080",
red: "#ff0000",
rosybrown: "#bc8f8f",
royalblue: "#4169e1",
saddlebrown: "#8b4513",
salmon: "#fa8072",
sandybrown: "#f4a460",
seagreen: "#2e8b57",
seashell: "#fff5ee",
sienna: "#a0522d",
silver: "#c0c0c0",
skyblue: "#87ceeb",
slateblue: "#6a5acd",
slategray: "#708090",
snow: "#fffafa",
springgreen: "#00ff7f",
steelblue: "#4682b4",
tan: "#d2b48c",
teal: "#008080",
thistle: "#d8bfd8",
tomato: "#ff6347",
turquoise: "#40e0d0",
violet: "#ee82ee",
wheat: "#f5deb3",
white: "#ffffff",
whitesmoke: "#f5f5f5",
yellow: "#ffff00",
yellowgreen: "#9acd32"
};
// Maintain drawing state params during gl.save and gl.restore. see saveDrawState() and restoreDrawState()
var drawState = {}, drawStateStack = [];
// A fast simple shallow clone
function cloneObject(obj) {
var target = {};
for (var i in obj) {
if (obj.hasOwnProperty(i)) {
target[i] = obj[i];
}
}
return target;
}
function saveDrawState() {
var bakedDrawState = {
fillStyle: [drawState.fillStyle[0], drawState.fillStyle[1], drawState.fillStyle[2], drawState.fillStyle[3]],
strokeStyle: [drawState.strokeStyle[0], drawState.strokeStyle[1], drawState.strokeStyle[2], drawState.strokeStyle[3]],
globalAlpha: drawState.globalAlpha,
globalCompositeOperation: drawState.globalCompositeOperation,
lineCap: drawState.lineCap,
lineJoin: drawState.lineJoin,
lineWidth: drawState.lineWidth,
miterLimit: drawState.miterLimit,
shadowColor: drawState.shadowColor,
shadowBlur: drawState.shadowBlur,
shadowOffsetX: drawState.shadowOffsetX,
shadowOffsetY: drawState.shadowOffsetY,
textAlign: drawState.textAlign,
font: drawState.font,
textBaseline: drawState.textBaseline
};
drawStateStack.push(bakedDrawState);
}
function restoreDrawState() {
if (drawStateStack.length) {
drawState = drawStateStack.pop();
}
}
// WebGL requires colors as a vector while Canvas2D sets colors as an rgba string
// These getters and setters store the original rgba string as well as convert to a vector
drawState.fillStyle = [0, 0, 0, 1]; // default black
Object.defineProperty(gl, "fillStyle", {
get: function() { return colorVecToString(drawState.fillStyle); },
set: function(value) {
drawState.fillStyle = colorStringToVec4(value) || drawState.fillStyle;
}
});
drawState.strokeStyle = [0, 0, 0, 1]; // default black
Object.defineProperty(gl, "strokeStyle", {
get: function() { return colorVecToString(drawState.strokeStyle); },
set: function(value) {
drawState.strokeStyle = colorStringToVec4(value) || drawStyle.strokeStyle;
}
});
// WebGL already has a lineWidth() function but Canvas2D requires a lineWidth property
// Store the original lineWidth() function for later use
gl.$lineWidth = gl.lineWidth;
drawState.lineWidth = 1.0;
Object.defineProperty(gl, "lineWidth", {
get: function() { return drawState.lineWidth; },
set: function(value) {
gl.$lineWidth(value);
drawState.lineWidth = value;
}
});
// Currently unsupported attributes and their default values
drawState.lineCap = "butt";
Object.defineProperty(gl, "lineCap", {
get: function() { return drawState.lineCap; },
set: function(value) {
drawState.lineCap = value;
}
});
drawState.lineJoin = "miter";
Object.defineProperty(gl, "lineJoin", {
get: function() { return drawState.lineJoin; },
set: function(value) {
drawState.lineJoin = value;
}
});
drawState.miterLimit = 10;
Object.defineProperty(gl, "miterLimit", {
get: function() { return drawState.miterLimit; },
set: function(value) {
drawState.miterLimit = value;
}
});
drawState.shadowOffsetX = 0;
Object.defineProperty(gl, "shadowOffsetX", {
get: function() { return drawState.shadowOffsetX; },
set: function(value) {
drawState.shadowOffsetX = value;
}
});
drawState.shadowOffsetY = 0;
Object.defineProperty(gl, "shadowOffsetY", {
get: function() { return drawState.shadowOffsetY; },
set: function(value) {
drawState.shadowOffsetY = value;
}
});
drawState.shadowBlur = 0;
Object.defineProperty(gl, "shadowBlur", {
get: function() { return drawState.shadowBlur; },
set: function(value) {
drawState.shadowBlur = value;
}
});
drawState.shadowColor = "rgba(0, 0, 0, 0.0)";
Object.defineProperty(gl, "shadowColor", {
get: function() { return drawState.shadowColor; },
set: function(value) {
drawState.shadowColor = value;
}
});
drawState.font = "10px sans-serif";
Object.defineProperty(gl, "font", {
get: function() { return drawState.font; },
set: function(value) {
textCtx.font = value;
drawState.font = value;
}
});
drawState.textAlign = "start";
Object.defineProperty(gl, "textAlign", {
get: function() { return drawState.textAlign; },
set: function(value) {
drawState.textAlign = value;
}
});
drawState.textBaseline = "alphabetic";
Object.defineProperty(gl, "textBaseline", {
get: function() { return drawState.textBaseline; },
set: function(value) {
drawState.textBaseline = value;
}
});
// This attribute will need to control global alpha of objects drawn.
drawState.globalAlpha = 1.0;
Object.defineProperty(gl, "globalAlpha", {
get: function() { return drawState.globalAlpha; },
set: function(value) {
drawState.globalAlpha = value;
}
});
// This attribute will need to set the gl.blendFunc mode
drawState.globalCompositeOperation = "source-over";
Object.defineProperty(gl, "globalCompositeOperation", {
get: function() { return drawState.globalCompositeOperation; },
set: function(value) {
drawState.globalCompositeOperation = value;
}
});
// Need a solution for drawing text that isnt stupid slow
gl.fillText = function fillText(text, x, y) {
/*
textCtx.clearRect(0, 0, gl2d.canvas.width, gl2d.canvas.height);
textCtx.fillStyle = gl.fillStyle;
textCtx.fillText(text, x, y);
gl.drawImage(textCanvas, 0, 0);
*/
};
gl.strokeText = function strokeText() {};
gl.measureText = function measureText() { return 1; };
var tempCanvas = document.createElement('canvas');
var tempCtx = tempCanvas.getContext('2d');
gl.save = function save() {
gl2d.transform.pushMatrix();
saveDrawState();
};
gl.restore = function restore() {
gl2d.transform.popMatrix();
restoreDrawState();
};
gl.translate = function translate(x, y) {
gl2d.transform.translate(x, y);
};
gl.rotate = function rotate(a) {
gl2d.transform.rotate(a);
};
gl.scale = function scale(x, y) {
gl2d.transform.scale(x, y);
};
gl.createImageData = function createImageData(width, height) {
return tempCtx.createImageData(width, height);
};
gl.getImageData = function getImageData(x, y, width, height) {
var data = tempCtx.createImageData(width, height);
var buffer = new Uint8Array(width*height*4);
gl.readPixels(x, y, width, height, gl.RGBA, gl.UNSIGNED_BYTE, buffer);
var w=width*4, h=height;
for (var i=0, maxI=h/2; i<maxI; ++i) {
for (var j=0, maxJ=w; j<maxJ; ++j) {
var index1 = i * w + j;
var index2 = (h-i-1) * w + j;
data.data[index1] = buffer[index2];
data.data[index2] = buffer[index1];
} //for
} //for
return data;
};
gl.putImageData = function putImageData(imageData, x, y) {
gl.drawImage(imageData, x, y);
};
gl.transform = function transform(m11, m12, m21, m22, dx, dy) {
var m = gl2d.transform.m_stack[gl2d.transform.c_stack];
m[0] *= m11;
m[1] *= m21;
m[2] *= dx;
m[3] *= m12;
m[4] *= m22;
m[5] *= dy;
m[6] = 0;
m[7] = 0;
};
function sendTransformStack(sp) {
var stack = gl2d.transform.m_stack;
for (var i = 0, maxI = gl2d.transform.c_stack + 1; i < maxI; ++i) {
gl.uniformMatrix3fv(sp.uTransforms[i], false, stack[maxI-1-i]);
} //for
}
gl.setTransform = function setTransform(m11, m12, m21, m22, dx, dy) {
gl2d.transform.setIdentity();
gl.transform.apply(this, arguments);
};
gl.fillRect = function fillRect(x, y, width, height) {
var transform = gl2d.transform;
var shaderProgram = gl2d.initShaders(transform.c_stack+2,0);
gl.bindBuffer(gl.ARRAY_BUFFER, rectVertexPositionBuffer);
gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, 4, gl.FLOAT, false, 0, 0);
transform.pushMatrix();
transform.translate(x, y);
transform.scale(width, height);
sendTransformStack(shaderProgram);
gl.uniform4f(shaderProgram.uColor, drawState.fillStyle[0], drawState.fillStyle[1], drawState.fillStyle[2], drawState.fillStyle[3]);
gl.drawArrays(gl.TRIANGLE_FAN, 0, 4);
transform.popMatrix();
};
gl.strokeRect = function strokeRect(x, y, width, height) {
var transform = gl2d.transform;
var shaderProgram = gl2d.initShaders(transform.c_stack + 2,0);
gl.bindBuffer(gl.ARRAY_BUFFER, rectVertexPositionBuffer);
gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, 4, gl.FLOAT, false, 0, 0);
transform.pushMatrix();
transform.translate(x, y);
transform.scale(width, height);
sendTransformStack(shaderProgram);
gl.uniform4f(shaderProgram.uColor, drawState.strokeStyle[0], drawState.strokeStyle[1], drawState.strokeStyle[2], drawState.strokeStyle[3]);
gl.drawArrays(gl.LINE_LOOP, 0, 4);
transform.popMatrix();
};
gl.clearRect = function clearRect(x, y, width, height) {};
var subPaths = [];
function SubPath(x, y) {
this.closed = false;
this.verts = [x, y, 0, 0];
}
// Empty the list of subpaths so that the context once again has zero subpaths
gl.beginPath = function beginPath() {
subPaths.length = 0;
};
// Mark last subpath as closed and create a new subpath with the same starting point as the previous subpath
gl.closePath = function closePath() {
if (subPaths.length) {
// Mark last subpath closed.
var prevPath = subPaths[subPaths.length -1], startX = prevPath.verts[0], startY = prevPath.verts[1];
prevPath.closed = true;
// Create new subpath using the starting position of previous subpath
var newPath = new SubPath(startX, startY);
subPaths.push(newPath);
}
};
// Create a new subpath with the specified point as its first (and only) point
gl.moveTo = function moveTo(x, y) {
subPaths.push(new SubPath(x, y));
};
gl.lineTo = function lineTo(x, y) {
if (subPaths.length) {
subPaths[subPaths.length -1].verts.push(x, y, 0, 0);
} else {
// Create a new subpath if none currently exist
gl.moveTo(x, y);
}
};
gl.quadraticCurveTo = function quadraticCurveTo(cp1x, cp1y, x, y) {};
gl.bezierCurveTo = function bezierCurveTo(cp1x, cp1y, cp2x, cp2y, x, y) {};
gl.arcTo = function arcTo() {};
// Adds a closed rect subpath and creates a new subpath
gl.rect = function rect(x, y, w, h) {
gl.moveTo(x, y);
gl.lineTo(x + w, y);
gl.lineTo(x + w, y + h);
gl.lineTo(x, y + h);
gl.closePath();
};
gl.arc = function arc(x, y, radius, startAngle, endAngle, anticlockwise) {};
function fillSubPath(index) {
var transform = gl2d.transform;
var shaderProgram = gl2d.initShaders(transform.c_stack + 2,0);
var subPath = subPaths[index];
var verts = subPath.verts;
gl.bindBuffer(gl.ARRAY_BUFFER, pathVertexPositionBuffer);
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(verts), gl.STATIC_DRAW);
gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, 4, gl.FLOAT, false, 0, 0);
transform.pushMatrix();
sendTransformStack(shaderProgram);
gl.uniform4f(shaderProgram.uColor, drawState.fillStyle[0], drawState.fillStyle[1], drawState.fillStyle[2], drawState.fillStyle[3]);
gl.drawArrays(gl.TRIANGLE_FAN, 0, verts.length/4);
transform.popMatrix();
}
gl.fill = function fill() {
for(var i = 0; i < subPaths.length; i++) {
fillSubPath(i);
}
};
function strokeSubPath(index) {
var transform = gl2d.transform;
var shaderProgram = gl2d.initShaders(transform.c_stack + 2,0);
var subPath = subPaths[index];
var verts = subPath.verts;
gl.bindBuffer(gl.ARRAY_BUFFER, pathVertexPositionBuffer);
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(verts), gl.STATIC_DRAW);
gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, 4, gl.FLOAT, false, 0, 0);
transform.pushMatrix();
sendTransformStack(shaderProgram);
gl.uniform4f(shaderProgram.uColor, drawState.strokeStyle[0], drawState.strokeStyle[1], drawState.strokeStyle[2], drawState.strokeStyle[3]);
if (subPath.closed) {
gl.drawArrays(gl.LINE_LOOP, 0, verts.length/4);
} else {
gl.drawArrays(gl.LINE_STRIP, 0, verts.length/4);
}
transform.popMatrix();
}
gl.stroke = function stroke() {
for(var i = 0; i < subPaths.length; i++) {
strokeSubPath(i);
}
};
gl.clip = function clip() {};
gl.isPointInPath = function isPointInPath() {};
gl.drawFocusRing = function drawFocusRing() {};
var imageCache = [], textureCache = [];
function Texture(image) {
this.obj = gl.createTexture();
this.index = textureCache.push(this);
imageCache.push(image);
// we may wish to consider tiling large images like this instead of scaling and
// adjust appropriately (flip to next texture source and tile offset) when drawing
if (image.width > gl2d.maxTextureSize || image.height > gl2d.maxTextureSize) {
var canvas = document.createElement("canvas");
canvas.width = (image.width > gl2d.maxTextureSize) ? gl2d.maxTextureSize : image.width;
canvas.height = (image.height > gl2d.maxTextureSize) ? gl2d.maxTextureSize : image.height;
var ctx = canvas.getContext("2d");
ctx.drawImage(image, 0, 0, image.width, image.height, 0, 0, canvas.width, canvas.height);
image = canvas;
}
gl.bindTexture(gl.TEXTURE_2D, this.obj);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, image);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
// Enable Mip mapping on power-of-2 textures
if (isPOT(image.width) && isPOT(image.height)) {
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_LINEAR);
gl.generateMipmap(gl.TEXTURE_2D);
} else {
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
}
// Unbind texture
gl.bindTexture(gl.TEXTURE_2D, null);
}
gl.drawImage = function drawImage(image, a, b, c, d, e, f, g, h) {
var transform = gl2d.transform;
transform.pushMatrix();
var sMask = shaderMask.texture;
var doCrop = false;
//drawImage(image, dx, dy)
if (arguments.length === 3) {
transform.translate(a, b);
transform.scale(image.width, image.height);
}
//drawImage(image, dx, dy, dw, dh)
else if (arguments.length === 5) {
transform.translate(a, b);
transform.scale(c, d);
}
//drawImage(image, sx, sy, sw, sh, dx, dy, dw, dh)
else if (arguments.length === 9) {
transform.translate(e, f);
transform.scale(g, h);
sMask = sMask|shaderMask.crop;
doCrop = true;
}
var shaderProgram = gl2d.initShaders(transform.c_stack, sMask);
var texture, cacheIndex = imageCache.indexOf(image);
if (cacheIndex !== -1) {
texture = textureCache[cacheIndex];
} else {
texture = new Texture(image);
}
if (doCrop) {
gl.uniform4f(shaderProgram.uCropSource, a/image.width, b/image.height, c/image.width, d/image.height);
}
gl.bindBuffer(gl.ARRAY_BUFFER, rectVertexPositionBuffer);
gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, 4, gl.FLOAT, false, 0, 0);
gl.bindTexture(gl.TEXTURE_2D, texture.obj);
gl.activeTexture(gl.TEXTURE0);
gl.uniform1i(shaderProgram.uSampler, 0);
sendTransformStack(shaderProgram);
gl.drawArrays(gl.TRIANGLE_FAN, 0, 4);
transform.popMatrix();
};
};
}(Math));
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