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Created November 7, 2012 15:47
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Safari WebGL Issues
Raw
README.md

Safari WebGL Issues

Raw
index.html
<html>
<head>
<script src="webgl-debug.js"></script>
<script src="webgl-utils.js"></script>
<script src="main.js"></script>
<script id="2d-vertex-shader" type="x-shader/x-vertex">
attribute vec2 a_position;
void main() {
gl_Position = vec4(a_position, 0, 1);
}
</script>
<script id="2d-fragment-shader" type="x-shader/x-fragment">
precision mediump float;
uniform vec2 u_resolution;
uniform sampler2D u_tex;
void main() {
vec2 texCoord = gl_FragCoord.xy / u_resolution;
vec4 pixel_v = texture2D(u_tex, texCoord);
float value = pixel_v[0];
float min = 0.0;
float max = 10.0;
float range = max - min;
float pixel = (value - min) / range;
gl_FragColor = vec4(vec3(pixel, pixel, pixel), 1.0);
}
</script>
</head>
<body onload='main()'>
<canvas id="canvas" width="400" height="300"></canvas>
</body>
</html>
Raw
main.js
function main() {
var canvas = document.getElementById("canvas");
var gl = getWebGLContext(canvas);
window.gl = gl;
if (!gl) {
alert("no WebGL");
return;
}
var ext = gl.getExtension("OES_texture_float");
if (!ext) {
alert("no OES_texture_float");
return;
}
vertexShader = createShaderFromScriptElement(gl, "2d-vertex-shader");
fragmentShader = createShaderFromScriptElement(gl, "2d-fragment-shader");
program = createProgram(gl, [vertexShader, fragmentShader]);
gl.useProgram(program);
var positionLocation = gl.getAttribLocation(program, "a_position");
var resolutionLocation = gl.getUniformLocation(program, "u_resolution");
gl.uniform2f(resolutionLocation, canvas.width, canvas.height);
var buffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, buffer);
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array([
-1, -1, 1, -1, -1, 1,
-1, 1, 1, -1, 1, 1]), gl.STATIC_DRAW);
gl.enableVertexAttribArray(positionLocation);
gl.vertexAttribPointer(positionLocation, 2, gl.FLOAT, false, 0, 0);
var tex = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, tex);
var width = 64;
var height = 64;
var pixels = new Float32Array(width * height);
for (var y = 0; y < height; ++y) {
for (var x = 0; x < width; ++x) {
var offset = y * width + x;
pixels[offset] = 10 * (x / width + y / height) * 0.5;
}
}
gl.texImage2D(
gl.TEXTURE_2D, 0,
gl.LUMINANCE, width, height, 0,
gl.LUMINANCE, gl.FLOAT, pixels);
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_MIN_FILTER, gl.NEAREST);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
gl.drawArrays(gl.TRIANGLES, 0, 6);
console.log(gl.getError());
}
Raw
webgl-debug.js
/*
** Copyright (c) 2012 The Khronos Group Inc.
**
** Permission is hereby granted, free of charge, to any person obtaining a
** copy of this software and/or associated documentation files (the
** "Materials"), to deal in the Materials without restriction, including
** without limitation the rights to use, copy, modify, merge, publish,
** distribute, sublicense, and/or sell copies of the Materials, and to
** permit persons to whom the Materials are 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 Materials.
**
** THE MATERIALS ARE 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
** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
*/
// Various functions for helping debug WebGL apps.
WebGLDebugUtils = function() {
/**
* Wrapped logging function.
* @param {string} msg Message to log.
*/
var log = function(msg) {
if (window.console && window.console.log) {
window.console.log(msg);
}
};
/**
* Wrapped error logging function.
* @param {string} msg Message to log.
*/
var error = function(msg) {
if (window.console && window.console.error) {
window.console.error(msg);
} else {
log(msg);
}
};
/**
* Which arguements are enums.
* @type {!Object.<number, string>}
*/
var glValidEnumContexts = {
// Generic setters and getters
'enable': { 0:true },
'disable': { 0:true },
'getParameter': { 0:true },
// Rendering
'drawArrays': { 0:true },
'drawElements': { 0:true, 2:true },
// Shaders
'createShader': { 0:true },
'getShaderParameter': { 1:true },
'getProgramParameter': { 1:true },
// Vertex attributes
'getVertexAttrib': { 1:true },
'vertexAttribPointer': { 2:true },
// Textures
'bindTexture': { 0:true },
'activeTexture': { 0:true },
'getTexParameter': { 0:true, 1:true },
'texParameterf': { 0:true, 1:true },
'texParameteri': { 0:true, 1:true, 2:true },
'texImage2D': { 0:true, 2:true, 6:true, 7:true },
'texSubImage2D': { 0:true, 6:true, 7:true },
'copyTexImage2D': { 0:true, 2:true },
'copyTexSubImage2D': { 0:true },
'generateMipmap': { 0:true },
// Buffer objects
'bindBuffer': { 0:true },
'bufferData': { 0:true, 2:true },
'bufferSubData': { 0:true },
'getBufferParameter': { 0:true, 1:true },
// Renderbuffers and framebuffers
'pixelStorei': { 0:true, 1:true },
'readPixels': { 4:true, 5:true },
'bindRenderbuffer': { 0:true },
'bindFramebuffer': { 0:true },
'checkFramebufferStatus': { 0:true },
'framebufferRenderbuffer': { 0:true, 1:true, 2:true },
'framebufferTexture2D': { 0:true, 1:true, 2:true },
'getFramebufferAttachmentParameter': { 0:true, 1:true, 2:true },
'getRenderbufferParameter': { 0:true, 1:true },
'renderbufferStorage': { 0:true, 1:true },
// Frame buffer operations (clear, blend, depth test, stencil)
'clear': { 0:true },
'depthFunc': { 0:true },
'blendFunc': { 0:true, 1:true },
'blendFuncSeparate': { 0:true, 1:true, 2:true, 3:true },
'blendEquation': { 0:true },
'blendEquationSeparate': { 0:true, 1:true },
'stencilFunc': { 0:true },
'stencilFuncSeparate': { 0:true, 1:true },
'stencilMaskSeparate': { 0:true },
'stencilOp': { 0:true, 1:true, 2:true },
'stencilOpSeparate': { 0:true, 1:true, 2:true, 3:true },
// Culling
'cullFace': { 0:true },
'frontFace': { 0:true },
};
/**
* Map of numbers to names.
* @type {Object}
*/
var glEnums = null;
/**
* Initializes this module. Safe to call more than once.
* @param {!WebGLRenderingContext} ctx A WebGL context. If
* you have more than one context it doesn't matter which one
* you pass in, it is only used to pull out constants.
*/
function init(ctx) {
if (glEnums == null) {
glEnums = { };
for (var propertyName in ctx) {
if (typeof ctx[propertyName] == 'number') {
glEnums[ctx[propertyName]] = propertyName;
}
}
}
}
/**
* Checks the utils have been initialized.
*/
function checkInit() {
if (glEnums == null) {
throw 'WebGLDebugUtils.init(ctx) not called';
}
}
/**
* Returns true or false if value matches any WebGL enum
* @param {*} value Value to check if it might be an enum.
* @return {boolean} True if value matches one of the WebGL defined enums
*/
function mightBeEnum(value) {
checkInit();
return (glEnums[value] !== undefined);
}
/**
* Gets an string version of an WebGL enum.
*
* Example:
* var str = WebGLDebugUtil.glEnumToString(ctx.getError());
*
* @param {number} value Value to return an enum for
* @return {string} The string version of the enum.
*/
function glEnumToString(value) {
checkInit();
var name = glEnums[value];
return (name !== undefined) ? name :
("*UNKNOWN WebGL ENUM (0x" + value.toString(16) + ")");
}
/**
* Returns the string version of a WebGL argument.
* Attempts to convert enum arguments to strings.
* @param {string} functionName the name of the WebGL function.
* @param {number} argumentIndx the index of the argument.
* @param {*} value The value of the argument.
* @return {string} The value as a string.
*/
function glFunctionArgToString(functionName, argumentIndex, value) {
var funcInfo = glValidEnumContexts[functionName];
if (funcInfo !== undefined) {
if (funcInfo[argumentIndex]) {
return glEnumToString(value);
}
}
if (value === null) {
return "null";
} else if (value === undefined) {
return "undefined";
} else {
return value.toString();
}
}
/**
* Converts the arguments of a WebGL function to a string.
* Attempts to convert enum arguments to strings.
*
* @param {string} functionName the name of the WebGL function.
* @param {number} args The arguments.
* @return {string} The arguments as a string.
*/
function glFunctionArgsToString(functionName, args) {
// apparently we can't do args.join(",");
var argStr = "";
for (var ii = 0; ii < args.length; ++ii) {
argStr += ((ii == 0) ? '' : ', ') +
glFunctionArgToString(functionName, ii, args[ii]);
}
return argStr;
};
function makePropertyWrapper(wrapper, original, propertyName) {
//log("wrap prop: " + propertyName);
wrapper.__defineGetter__(propertyName, function() {
return original[propertyName];
});
// TODO(gmane): this needs to handle properties that take more than
// one value?
wrapper.__defineSetter__(propertyName, function(value) {
//log("set: " + propertyName);
original[propertyName] = value;
});
}
// Makes a function that calls a function on another object.
function makeFunctionWrapper(original, functionName) {
//log("wrap fn: " + functionName);
var f = original[functionName];
return function() {
//log("call: " + functionName);
var result = f.apply(original, arguments);
return result;
};
}
/**
* Given a WebGL context returns a wrapped context that calls
* gl.getError after every command and calls a function if the
* result is not gl.NO_ERROR.
*
* @param {!WebGLRenderingContext} ctx The webgl context to
* wrap.
* @param {!function(err, funcName, args): void} opt_onErrorFunc
* The function to call when gl.getError returns an
* error. If not specified the default function calls
* console.log with a message.
* @param {!function(funcName, args): void} opt_onFunc The
* function to call when each webgl function is called.
* You can use this to log all calls for example.
*/
function makeDebugContext(ctx, opt_onErrorFunc, opt_onFunc) {
init(ctx);
opt_onErrorFunc = opt_onErrorFunc || function(err, functionName, args) {
// apparently we can't do args.join(",");
var argStr = "";
for (var ii = 0; ii < args.length; ++ii) {
argStr += ((ii == 0) ? '' : ', ') +
glFunctionArgToString(functionName, ii, args[ii]);
}
error("WebGL error "+ glEnumToString(err) + " in "+ functionName +
"(" + argStr + ")");
};
// Holds booleans for each GL error so after we get the error ourselves
// we can still return it to the client app.
var glErrorShadow = { };
// Makes a function that calls a WebGL function and then calls getError.
function makeErrorWrapper(ctx, functionName) {
return function() {
if (opt_onFunc) {
opt_onFunc(functionName, arguments);
}
var result = ctx[functionName].apply(ctx, arguments);
var err = ctx.getError();
if (err != 0) {
glErrorShadow[err] = true;
opt_onErrorFunc(err, functionName, arguments);
}
return result;
};
}
// Make a an object that has a copy of every property of the WebGL context
// but wraps all functions.
var wrapper = {};
for (var propertyName in ctx) {
if (typeof ctx[propertyName] == 'function') {
wrapper[propertyName] = makeErrorWrapper(ctx, propertyName);
} else {
makePropertyWrapper(wrapper, ctx, propertyName);
}
}
// Override the getError function with one that returns our saved results.
wrapper.getError = function() {
for (var err in glErrorShadow) {
if (glErrorShadow.hasOwnProperty(err)) {
if (glErrorShadow[err]) {
glErrorShadow[err] = false;
return err;
}
}
}
return ctx.NO_ERROR;
};
return wrapper;
}
function resetToInitialState(ctx) {
var numAttribs = ctx.getParameter(ctx.MAX_VERTEX_ATTRIBS);
var tmp = ctx.createBuffer();
ctx.bindBuffer(ctx.ARRAY_BUFFER, tmp);
for (var ii = 0; ii < numAttribs; ++ii) {
ctx.disableVertexAttribArray(ii);
ctx.vertexAttribPointer(ii, 4, ctx.FLOAT, false, 0, 0);
ctx.vertexAttrib1f(ii, 0);
}
ctx.deleteBuffer(tmp);
var numTextureUnits = ctx.getParameter(ctx.MAX_TEXTURE_IMAGE_UNITS);
for (var ii = 0; ii < numTextureUnits; ++ii) {
ctx.activeTexture(ctx.TEXTURE0 + ii);
ctx.bindTexture(ctx.TEXTURE_CUBE_MAP, null);
ctx.bindTexture(ctx.TEXTURE_2D, null);
}
ctx.activeTexture(ctx.TEXTURE0);
ctx.useProgram(null);
ctx.bindBuffer(ctx.ARRAY_BUFFER, null);
ctx.bindBuffer(ctx.ELEMENT_ARRAY_BUFFER, null);
ctx.bindFramebuffer(ctx.FRAMEBUFFER, null);
ctx.bindRenderbuffer(ctx.RENDERBUFFER, null);
ctx.disable(ctx.BLEND);
ctx.disable(ctx.CULL_FACE);
ctx.disable(ctx.DEPTH_TEST);
ctx.disable(ctx.DITHER);
ctx.disable(ctx.SCISSOR_TEST);
ctx.blendColor(0, 0, 0, 0);
ctx.blendEquation(ctx.FUNC_ADD);
ctx.blendFunc(ctx.ONE, ctx.ZERO);
ctx.clearColor(0, 0, 0, 0);
ctx.clearDepth(1);
ctx.clearStencil(-1);
ctx.colorMask(true, true, true, true);
ctx.cullFace(ctx.BACK);
ctx.depthFunc(ctx.LESS);
ctx.depthMask(true);
ctx.depthRange(0, 1);
ctx.frontFace(ctx.CCW);
ctx.hint(ctx.GENERATE_MIPMAP_HINT, ctx.DONT_CARE);
ctx.lineWidth(1);
ctx.pixelStorei(ctx.PACK_ALIGNMENT, 4);
ctx.pixelStorei(ctx.UNPACK_ALIGNMENT, 4);
ctx.pixelStorei(ctx.UNPACK_FLIP_Y_WEBGL, false);
ctx.pixelStorei(ctx.UNPACK_PREMULTIPLY_ALPHA_WEBGL, false);
// TODO: Delete this IF.
if (ctx.UNPACK_COLORSPACE_CONVERSION_WEBGL) {
ctx.pixelStorei(ctx.UNPACK_COLORSPACE_CONVERSION_WEBGL, ctx.BROWSER_DEFAULT_WEBGL);
}
ctx.polygonOffset(0, 0);
ctx.sampleCoverage(1, false);
ctx.scissor(0, 0, ctx.canvas.width, ctx.canvas.height);
ctx.stencilFunc(ctx.ALWAYS, 0, 0xFFFFFFFF);
ctx.stencilMask(0xFFFFFFFF);
ctx.stencilOp(ctx.KEEP, ctx.KEEP, ctx.KEEP);
ctx.viewport(0, 0, ctx.canvas.width, ctx.canvas.height);
ctx.clear(ctx.COLOR_BUFFER_BIT | ctx.DEPTH_BUFFER_BIT | ctx.STENCIL_BUFFER_BIT);
// TODO: This should NOT be needed but Firefox fails with 'hint'
while(ctx.getError());
}
function makeLostContextSimulatingCanvas(canvas) {
var unwrappedContext_;
var wrappedContext_;
var onLost_ = [];
var onRestored_ = [];
var wrappedContext_ = {};
var contextId_ = 1;
var contextLost_ = false;
var resourceId_ = 0;
var resourceDb_ = [];
var numCallsToLoseContext_ = 0;
var numCalls_ = 0;
var canRestore_ = false;
var restoreTimeout_ = 0;
// Holds booleans for each GL error so can simulate errors.
var glErrorShadow_ = { };
canvas.getContext = function(f) {
return function() {
var ctx = f.apply(canvas, arguments);
// Did we get a context and is it a WebGL context?
if (ctx instanceof WebGLRenderingContext) {
if (ctx != unwrappedContext_) {
if (unwrappedContext_) {
throw "got different context"
}
unwrappedContext_ = ctx;
wrappedContext_ = makeLostContextSimulatingContext(unwrappedContext_);
}
return wrappedContext_;
}
return ctx;
}
}(canvas.getContext);
function wrapEvent(listener) {
if (typeof(listener) == "function") {
return listener;
} else {
return function(info) {
listener.handleEvent(info);
}
}
}
var addOnContextLostListener = function(listener) {
onLost_.push(wrapEvent(listener));
};
var addOnContextRestoredListener = function(listener) {
onRestored_.push(wrapEvent(listener));
};
function wrapAddEventListener(canvas) {
var f = canvas.addEventListener;
canvas.addEventListener = function(type, listener, bubble) {
switch (type) {
case 'webglcontextlost':
addOnContextLostListener(listener);
break;
case 'webglcontextrestored':
addOnContextRestoredListener(listener);
break;
default:
f.apply(canvas, arguments);
}
};
}
wrapAddEventListener(canvas);
canvas.loseContext = function() {
if (!contextLost_) {
contextLost_ = true;
numCallsToLoseContext_ = 0;
++contextId_;
while (unwrappedContext_.getError());
clearErrors();
glErrorShadow_[unwrappedContext_.CONTEXT_LOST_WEBGL] = true;
var event = makeWebGLContextEvent("context lost");
var callbacks = onLost_.slice();
setTimeout(function() {
//log("numCallbacks:" + callbacks.length);
for (var ii = 0; ii < callbacks.length; ++ii) {
//log("calling callback:" + ii);
callbacks[ii](event);
}
if (restoreTimeout_ >= 0) {
setTimeout(function() {
canvas.restoreContext();
}, restoreTimeout_);
}
}, 0);
}
};
canvas.restoreContext = function() {
if (contextLost_) {
if (onRestored_.length) {
setTimeout(function() {
if (!canRestore_) {
throw "can not restore. webglcontestlost listener did not call event.preventDefault";
}
freeResources();
resetToInitialState(unwrappedContext_);
contextLost_ = false;
numCalls_ = 0;
canRestore_ = false;
var callbacks = onRestored_.slice();
var event = makeWebGLContextEvent("context restored");
for (var ii = 0; ii < callbacks.length; ++ii) {
callbacks[ii](event);
}
}, 0);
}
}
};
canvas.loseContextInNCalls = function(numCalls) {
if (contextLost_) {
throw "You can not ask a lost contet to be lost";
}
numCallsToLoseContext_ = numCalls_ + numCalls;
};
canvas.getNumCalls = function() {
return numCalls_;
};
canvas.setRestoreTimeout = function(timeout) {
restoreTimeout_ = timeout;
};
function isWebGLObject(obj) {
//return false;
return (obj instanceof WebGLBuffer ||
obj instanceof WebGLFramebuffer ||
obj instanceof WebGLProgram ||
obj instanceof WebGLRenderbuffer ||
obj instanceof WebGLShader ||
obj instanceof WebGLTexture);
}
function checkResources(args) {
for (var ii = 0; ii < args.length; ++ii) {
var arg = args[ii];
if (isWebGLObject(arg)) {
return arg.__webglDebugContextLostId__ == contextId_;
}
}
return true;
}
function clearErrors() {
var k = Object.keys(glErrorShadow_);
for (var ii = 0; ii < k.length; ++ii) {
delete glErrorShadow_[k];
}
}
function loseContextIfTime() {
++numCalls_;
if (!contextLost_) {
if (numCallsToLoseContext_ == numCalls_) {
canvas.loseContext();
}
}
}
// Makes a function that simulates WebGL when out of context.
function makeLostContextFunctionWrapper(ctx, functionName) {
var f = ctx[functionName];
return function() {
// log("calling:" + functionName);
// Only call the functions if the context is not lost.
loseContextIfTime();
if (!contextLost_) {
//if (!checkResources(arguments)) {
// glErrorShadow_[wrappedContext_.INVALID_OPERATION] = true;
// return;
//}
var result = f.apply(ctx, arguments);
return result;
}
};
}
function freeResources() {
for (var ii = 0; ii < resourceDb_.length; ++ii) {
var resource = resourceDb_[ii];
if (resource instanceof WebGLBuffer) {
unwrappedContext_.deleteBuffer(resource);
} else if (resource instanceof WebGLFramebuffer) {
unwrappedContext_.deleteFramebuffer(resource);
} else if (resource instanceof WebGLProgram) {
unwrappedContext_.deleteProgram(resource);
} else if (resource instanceof WebGLRenderbuffer) {
unwrappedContext_.deleteRenderbuffer(resource);
} else if (resource instanceof WebGLShader) {
unwrappedContext_.deleteShader(resource);
} else if (resource instanceof WebGLTexture) {
unwrappedContext_.deleteTexture(resource);
}
}
}
function makeWebGLContextEvent(statusMessage) {
return {
statusMessage: statusMessage,
preventDefault: function() {
canRestore_ = true;
}
};
}
return canvas;
function makeLostContextSimulatingContext(ctx) {
// copy all functions and properties to wrapper
for (var propertyName in ctx) {
if (typeof ctx[propertyName] == 'function') {
wrappedContext_[propertyName] = makeLostContextFunctionWrapper(
ctx, propertyName);
} else {
makePropertyWrapper(wrappedContext_, ctx, propertyName);
}
}
// Wrap a few functions specially.
wrappedContext_.getError = function() {
loseContextIfTime();
if (!contextLost_) {
var err;
while (err = unwrappedContext_.getError()) {
glErrorShadow_[err] = true;
}
}
for (var err in glErrorShadow_) {
if (glErrorShadow_[err]) {
delete glErrorShadow_[err];
return err;
}
}
return wrappedContext_.NO_ERROR;
};
var creationFunctions = [
"createBuffer",
"createFramebuffer",
"createProgram",
"createRenderbuffer",
"createShader",
"createTexture"
];
for (var ii = 0; ii < creationFunctions.length; ++ii) {
var functionName = creationFunctions[ii];
wrappedContext_[functionName] = function(f) {
return function() {
loseContextIfTime();
if (contextLost_) {
return null;
}
var obj = f.apply(ctx, arguments);
obj.__webglDebugContextLostId__ = contextId_;
resourceDb_.push(obj);
return obj;
};
}(ctx[functionName]);
}
var functionsThatShouldReturnNull = [
"getActiveAttrib",
"getActiveUniform",
"getBufferParameter",
"getContextAttributes",
"getAttachedShaders",
"getFramebufferAttachmentParameter",
"getParameter",
"getProgramParameter",
"getProgramInfoLog",
"getRenderbufferParameter",
"getShaderParameter",
"getShaderInfoLog",
"getShaderSource",
"getTexParameter",
"getUniform",
"getUniformLocation",
"getVertexAttrib"
];
for (var ii = 0; ii < functionsThatShouldReturnNull.length; ++ii) {
var functionName = functionsThatShouldReturnNull[ii];
wrappedContext_[functionName] = function(f) {
return function() {
loseContextIfTime();
if (contextLost_) {
return null;
}
return f.apply(ctx, arguments);
}
}(wrappedContext_[functionName]);
}
var isFunctions = [
"isBuffer",
"isEnabled",
"isFramebuffer",
"isProgram",
"isRenderbuffer",
"isShader",
"isTexture"
];
for (var ii = 0; ii < isFunctions.length; ++ii) {
var functionName = isFunctions[ii];
wrappedContext_[functionName] = function(f) {
return function() {
loseContextIfTime();
if (contextLost_) {
return false;
}
return f.apply(ctx, arguments);
}
}(wrappedContext_[functionName]);
}
wrappedContext_.checkFramebufferStatus = function(f) {
return function() {
loseContextIfTime();
if (contextLost_) {
return wrappedContext_.FRAMEBUFFER_UNSUPPORTED;
}
return f.apply(ctx, arguments);
};
}(wrappedContext_.checkFramebufferStatus);
wrappedContext_.getAttribLocation = function(f) {
return function() {
loseContextIfTime();
if (contextLost_) {
return -1;
}
return f.apply(ctx, arguments);
};
}(wrappedContext_.getAttribLocation);
wrappedContext_.getVertexAttribOffset = function(f) {
return function() {
loseContextIfTime();
if (contextLost_) {
return 0;
}
return f.apply(ctx, arguments);
};
}(wrappedContext_.getVertexAttribOffset);
wrappedContext_.isContextLost = function() {
return contextLost_;
};
return wrappedContext_;
}
}
return {
/**
* Initializes this module. Safe to call more than once.
* @param {!WebGLRenderingContext} ctx A WebGL context. If
}
* you have more than one context it doesn't matter which one
* you pass in, it is only used to pull out constants.
*/
'init': init,
/**
* Returns true or false if value matches any WebGL enum
* @param {*} value Value to check if it might be an enum.
* @return {boolean} True if value matches one of the WebGL defined enums
*/
'mightBeEnum': mightBeEnum,
/**
* Gets an string version of an WebGL enum.
*
* Example:
* WebGLDebugUtil.init(ctx);
* var str = WebGLDebugUtil.glEnumToString(ctx.getError());
*
* @param {number} value Value to return an enum for
* @return {string} The string version of the enum.
*/
'glEnumToString': glEnumToString,
/**
* Converts the argument of a WebGL function to a string.
* Attempts to convert enum arguments to strings.
*
* Example:
* WebGLDebugUtil.init(ctx);
* var str = WebGLDebugUtil.glFunctionArgToString('bindTexture', 0, gl.TEXTURE_2D);
*
* would return 'TEXTURE_2D'
*
* @param {string} functionName the name of the WebGL function.
* @param {number} argumentIndx the index of the argument.
* @param {*} value The value of the argument.
* @return {string} The value as a string.
*/
'glFunctionArgToString': glFunctionArgToString,
/**
* Converts the arguments of a WebGL function to a string.
* Attempts to convert enum arguments to strings.
*
* @param {string} functionName the name of the WebGL function.
* @param {number} args The arguments.
* @return {string} The arguments as a string.
*/
'glFunctionArgsToString': glFunctionArgsToString,
/**
* Given a WebGL context returns a wrapped context that calls
* gl.getError after every command and calls a function if the
* result is not NO_ERROR.
*
* You can supply your own function if you want. For example, if you'd like
* an exception thrown on any GL error you could do this
*
* function throwOnGLError(err, funcName, args) {
* throw WebGLDebugUtils.glEnumToString(err) +
* " was caused by call to " + funcName;
* };
*
* ctx = WebGLDebugUtils.makeDebugContext(
* canvas.getContext("webgl"), throwOnGLError);
*
* @param {!WebGLRenderingContext} ctx The webgl context to wrap.
* @param {!function(err, funcName, args): void} opt_onErrorFunc The function
* to call when gl.getError returns an error. If not specified the default
* function calls console.log with a message.
* @param {!function(funcName, args): void} opt_onFunc The
* function to call when each webgl function is called. You
* can use this to log all calls for example.
*/
'makeDebugContext': makeDebugContext,
/**
* Given a canvas element returns a wrapped canvas element that will
* simulate lost context. The canvas returned adds the following functions.
*
* loseContext:
* simulates a lost context event.
*
* restoreContext:
* simulates the context being restored.
*
* lostContextInNCalls:
* loses the context after N gl calls.
*
* getNumCalls:
* tells you how many gl calls there have been so far.
*
* setRestoreTimeout:
* sets the number of milliseconds until the context is restored
* after it has been lost. Defaults to 0. Pass -1 to prevent
* automatic restoring.
*
* @param {!Canvas} canvas The canvas element to wrap.
*/
'makeLostContextSimulatingCanvas': makeLostContextSimulatingCanvas,
/**
* Resets a context to the initial state.
* @param {!WebGLRenderingContext} ctx The webgl context to
* reset.
*/
'resetToInitialState': resetToInitialState
};
}();
Raw
webgl-utils.js
// Licensed under a BSD license. See ../license.html for license
// These funcitions are meant solely to help unclutter the tutorials.
// They are not meant as production type functions.
(function() {
/**
* Wrapped logging function.
* @param {string} msg The message to log.
*/
var log = function(msg) {
if (window.console && window.console.log) {
window.console.log(msg);
}
};
/**
* Wrapped logging function.
* @param {string} msg The message to log.
*/
var error = function(msg) {
if (window.console) {
if (window.console.error) {
window.console.error(msg);
}
else if (window.console.log) {
window.console.log(msg);
}
}
};
/**
* Turn off all logging.
*/
var loggingOff = function() {
log = function() {};
error = function() {};
};
/**
* Check if the page is embedded.
* @return {boolean} True of we are in an iframe
*/
var isInIFrame = function() {
return window != window.top;
};
/**
* Converts a WebGL enum to a string
* @param {!WebGLContext} gl The WebGLContext to use.
* @param {number} value The enum value.
* @return {string} The enum as a string.
*/
var glEnumToString = function(gl, value) {
for (var p in gl) {
if (gl[p] == value) {
return p;
}
}
return "0x" + value.toString(16);
};
/**
* Creates the HTLM for a failure message
* @param {string} canvasContainerId id of container of th
* canvas.
* @return {string} The html.
*/
var makeFailHTML = function(msg) {
return '' +
'<table style="background-color: #8CE; width: 100%; height: 100%;"><tr>' +
'<td align="center">' +
'<div style="display: table-cell; vertical-align: middle;">' +
'<div style="">' + msg + '</div>' +
'</div>' +
'</td></tr></table>';
};
/**
* Mesasge for getting a webgl browser
* @type {string}
*/
var GET_A_WEBGL_BROWSER = '' +
'This page requires a browser that supports WebGL.<br/>' +
'<a href="http://get.webgl.org">Click here to upgrade your browser.</a>';
/**
* Mesasge for need better hardware
* @type {string}
*/
var OTHER_PROBLEM = '' +
"It doesn't appear your computer can support WebGL.<br/>" +
'<a href="http://get.webgl.org/troubleshooting/">Click here for more information.</a>';
/**
* Creates a webgl context. If creation fails it will
* change the contents of the container of the <canvas>
* tag to an error message with the correct links for WebGL.
* @param {Element} canvas. The canvas element to create a
* context from.
* @param {WebGLContextCreationAttirbutes} opt_attribs Any
* creation attributes you want to pass in.
* @return {WebGLRenderingContext} The created context.
*/
var setupWebGL = function(canvas, opt_attribs) {
function showLink(str) {
var container = canvas.parentNode;
if (container) {
container.innerHTML = makeFailHTML(str);
}
};
if (!window.WebGLRenderingContext) {
showLink(GET_A_WEBGL_BROWSER);
return null;
}
var context = create3DContext(canvas, opt_attribs);
if (!context) {
showLink(OTHER_PROBLEM);
}
return context;
};
/**
* Creates a webgl context.
* @param {!Canvas} canvas The canvas tag to get context
* from. If one is not passed in one will be created.
* @return {!WebGLContext} The created context.
*/
var create3DContext = function(canvas, opt_attribs) {
var names = ["webgl", "experimental-webgl"];
var context = null;
for (var ii = 0; ii < names.length; ++ii) {
try {
context = canvas.getContext(names[ii], opt_attribs);
} catch(e) {}
if (context) {
break;
}
}
return context;
}
var updateCSSIfInIFrame = function() {
if (isInIFrame()) {
document.body.className = "iframe";
}
};
/**
* Gets a WebGL context.
* makes its backing store the size it is displayed.
*/
var getWebGLContext = function(canvas, opt_attribs) {
if (isInIFrame()) {
updateCSSIfInIFrame();
// make the canvas backing store the size it's displayed.
canvas.width = canvas.clientWidth;
canvas.height = canvas.clientHeight;
} else {
var title = document.title;
var h1 = document.createElement("h1");
h1.innerText = title;
document.body.insertBefore(h1, document.body.children[0]);
}
var gl = setupWebGL(canvas, opt_attribs);
return gl;
};
/**
* Loads a shader.
* @param {!WebGLContext} gl The WebGLContext to use.
* @param {string} shaderSource The shader source.
* @param {number} shaderType The type of shader.
* @param {function(string): void) opt_errorCallback callback for errors.
* @return {!WebGLShader} The created shader.
*/
var loadShader = function(gl, shaderSource, shaderType, opt_errorCallback) {
var errFn = opt_errorCallback || error;
// Create the shader object
var shader = gl.createShader(shaderType);
// Load the shader source
gl.shaderSource(shader, shaderSource);
// Compile the shader
gl.compileShader(shader);
// Check the compile status
var compiled = gl.getShaderParameter(shader, gl.COMPILE_STATUS);
if (!compiled) {
// Something went wrong during compilation; get the error
lastError = gl.getShaderInfoLog(shader);
errFn("*** Error compiling shader '" + shader + "':" + lastError);
gl.deleteShader(shader);
return null;
}
return shader;
}
/**
* Creates a program, attaches shaders, binds attrib locations, links the
* program and calls useProgram.
* @param {!Array.<!WebGLShader>} shaders The shaders to attach
* @param {!Array.<string>} opt_attribs The attribs names.
* @param {!Array.<number>} opt_locations The locations for the attribs.
* @param {function(string): void) opt_errorCallback callback for errors.
*/
var loadProgram = function(
gl, shaders, opt_attribs, opt_locations, opt_errorCallback) {
var errFn = opt_errorCallback || error;
var program = gl.createProgram();
for (var ii = 0; ii < shaders.length; ++ii) {
gl.attachShader(program, shaders[ii]);
}
if (opt_attribs) {
for (var ii = 0; ii < opt_attribs.length; ++ii) {
gl.bindAttribLocation(
program,
opt_locations ? opt_locations[ii] : ii,
opt_attribs[ii]);
}
}
gl.linkProgram(program);
// Check the link status
var linked = gl.getProgramParameter(program, gl.LINK_STATUS);
if (!linked) {
// something went wrong with the link
lastError = gl.getProgramInfoLog (program);
errFn("Error in program linking:" + lastError);
gl.deleteProgram(program);
return null;
}
return program;
};
/**
* Loads a shader from a script tag.
* @param {!WebGLContext} gl The WebGLContext to use.
* @param {string} scriptId The id of the script tag.
* @param {number} opt_shaderType The type of shader. If not passed in it will
* be derived from the type of the script tag.
* @param {function(string): void) opt_errorCallback callback for errors.
* @return {!WebGLShader} The created shader.
*/
var createShaderFromScript = function(
gl, scriptId, opt_shaderType, opt_errorCallback) {
var shaderSource = "";
var shaderType;
var shaderScript = document.getElementById(scriptId);
if (!shaderScript) {
throw("*** Error: unknown script element" + scriptId);
}
shaderSource = shaderScript.text;
if (!opt_shaderType) {
if (shaderScript.type == "x-shader/x-vertex") {
shaderType = gl.VERTEX_SHADER;
} else if (shaderScript.type == "x-shader/x-fragment") {
shaderType = gl.FRAGMENT_SHADER;
} else if (shaderType != gl.VERTEX_SHADER && shaderType != gl.FRAGMENT_SHADER) {
throw("*** Error: unknown shader type");
return null;
}
}
return loadShader(
gl, shaderSource, opt_shaderType ? opt_shaderType : shaderType,
opt_errorCallback);
};
var defaultShaderType = [
"VERTEX_SHADER",
"FRAGMENT_SHADER"
];
/**
* Creates a program from 2 script tags.
*
* @param {!WebGLContext} gl The WebGLContext to use.
* @param {!Array.<string>} shaderScriptIds Array of ids of the
* script tags for the shaders. The first is assumed to
* be the vertex shader, the second the fragment shader.
* @param {!Array.<string>} opt_attribs The attribs names.
* @param {!Array.<number>} opt_locations The locations for the attribs.
* @param {function(string): void) opt_errorCallback callback for errors.
* @return {!WebGLProgram} The created program.
*/
var createProgramFromScripts = function(
gl, shaderScriptIds, opt_attribs, opt_locations, opt_errorCallback) {
var shaders = [];
for (var ii = 0; ii < shaderScriptIds.length; ++ii) {
shaders.push(createShaderFromScript(
gl, shaderScriptIds[ii], gl[defaultShaderType[ii]], opt_errorCallback));
}
return loadProgram(gl, shaders, opt_attribs, opt_locations, opt_errorCallback);
};
// Add your prefix here.
var browserPrefixes = [
"",
"MOZ_",
"OP_",
"WEBKIT_"
];
/**
* Given an extension name like WEBGL_compressed_texture_s3tc
* returns the supported version extension, like
* WEBKIT_WEBGL_compressed_teture_s3tc
* @param {string} name Name of extension to look for
* @return {WebGLExtension} The extension or undefined if not
* found.
*/
var getExtensionWithKnownPrefixes = function(gl, name) {
for (var ii = 0; ii < browserPrefixes.length; ++ii) {
var prefixedName = browserPrefixes[ii] + name;
var ext = gl.getExtension(prefixedName);
if (ext) {
return ext;
}
}
};
/**
* Resize a canvas to match the size it's displayed.
* @param {!Canvas} canvas The canvas to resize.
*/
var resizeCanvasToDisplaySize = function(canvas) {
if (canvas.width != canvas.clientWidth ||
canvas.height != canvas.clientHeight) {
canvas.width = canvas.clientWidth;
canvas.height = canvas.clientHeight;
}
}
/* export functions */
this.createProgram = loadProgram;
this.createProgramFromScripts = createProgramFromScripts;
this.createShaderFromScriptElement = createShaderFromScript;
this.getWebGLContext = getWebGLContext;
this.updateCSSIfInIFrame = updateCSSIfInIFrame;
this.getExtensionWithKnownPrefixes = getExtensionWithKnownPrefixes;
this.resizeCanvasToDisplaySize = resizeCanvasToDisplaySize;
/**
* Provides requestAnimationFrame in a cross browser way.
*/
this.requestAnimFrame = (function() {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(/* function FrameRequestCallback */ callback, /* DOMElement Element */ element) {
return window.setTimeout(callback, 1000/60);
};
})();
/**
* Provides cancelRequestAnimationFrame in a cross browser way.
*/
this.cancelRequestAnimFrame = (function() {
return window.cancelCancelRequestAnimationFrame ||
window.webkitCancelRequestAnimationFrame ||
window.mozCancelRequestAnimationFrame ||
window.oCancelRequestAnimationFrame ||
window.msCancelRequestAnimationFrame ||
window.clearTimeout;
})();
}());
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