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mirror of https://github.com/kkapsner/CanvasBlocker synced 2024-12-22 21:00:23 +01:00

Test cleanup.

This commit is contained in:
kkapsner 2017-08-13 23:44:31 +02:00
parent d8f6fb1ac9
commit 7d0c9681df
11 changed files with 437 additions and 395 deletions

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@ -1,8 +1,7 @@
<!DOCTYPE html> <!DOCTYPE html>
<html> <html>
<head> <head>
<title>Detection Test</title> <title>Detection test</title>
<style> <style>
.notRun { .notRun {
color: lightgray; color: lightgray;
@ -19,170 +18,9 @@
</style> </style>
</head> </head>
<body> <body>
<h1>Detection test</h1>
Checks if the addon can be detected by websites.
<ul id="tests"></ul> <ul id="tests"></ul>
<script> <script src="detectionTest.js"></script>
var addTest = (function(){
var stati = [
{className: "notRun", text: "not run"},
{className: "loud", text: "CB detected"},
{className: "stealthy", text: "CB not detected"},
{className: "failed", text: "test failed"}
];
var ul = document.getElementById("tests");
return function addTest(name, func){
var logs = [];
function log(){
logs.push(Array.prototype.slice.call(arguments).join(" "));
}
var status = 0;
try {
status = func(log)? 1: 2;
}
catch (e){
console.log(e);
status = 3;
}
var li = document.createElement("li");
li.className = stati[status].className;
var nameNode = document.createElement("span");
nameNode.className = "name";
nameNode.textContent = name;
nameNode.title = func.toString();
li.appendChild(nameNode);
li.appendChild(document.createTextNode(": "));
var statusNode = document.createElement("span");
statusNode.className = "status";
statusNode.textContent = stati[status].text;
statusNode.title = logs.join("\n");
li.appendChild(statusNode);
ul.appendChild(li);
}
}());
addTest("function length", function(log){
if (CanvasRenderingContext2D.prototype.getImageData.length !== 4){
log("expected 4 parameters for getImageData - got", CanvasRenderingContext2D.prototype.getImageData.length);
return true;
}
else {
return false;
}
});
addTest("function code", function(log){
if (!CanvasRenderingContext2D.prototype.getImageData.toString().match(/^\s*function getImageData\s*\(\)\s*\{\s*\[native code\]\s*\}\s*$/)){
log("unexpected function code:", CanvasRenderingContext2D.prototype.getImageData.toString());
return true;
}
else {
return false;
}
});
addTest("function name", function(){return CanvasRenderingContext2D.prototype.getImageData.name !== "getImageData"});
addTest("error provocation 1", function(log){
var canvas = document.createElement('canvas');
var ctx = canvas.getContext("2d");
var canvasBlocker = false;
try{
ctx.getImageData(0, 0, 0, 0);
}
catch (err){
try {
log(err.name);
log(err.toString());
}
catch (e){
canvasBlocker = true;
}
}
return canvasBlocker;
});
addTest("error provocation 2", function(log){
var canvas = document.createElement('canvas');
canvas.width = 0;
var ctx = canvas.getContext("2d");
var canvasBlocker = false;
try{
ctx.getImageData(0, 0, 1, 1);
log("no error provoked");
}
catch (err){
try {
log(err.name);
log(err.toString());
}
catch (e){
canvasBlocker = true;
}
}
return canvasBlocker;
});
addTest("error provocation 3", function(log){
var canvasBlocker = false;
try{
CanvasRenderingContext2D.prototype.getImageData.apply(undefined, [0, 0, 1, 1]);
}
catch (err){
try {
log(err.name);
log(err.toString());
}
catch (e){
canvasBlocker = true;
}
}
return canvasBlocker;
});
function testKnownPixelValue(size, log){
var canvas = document.createElement("canvas");
canvas.height = size;
canvas.width = size;
var context = canvas.getContext("2d");
context.fillStyle = "rgba(0, 127, 255, 1)";
var pixelValues = [0, 127, 255, 255];
context.fillRect(0, 0, canvas.width, canvas.height);
var p = context.getImageData(0, 0, canvas.width, canvas.height).data;
for (var i = 0; i < p.length; i += 1){
if (p[i] !== pixelValues[i%4]){
log("wrong value", p[i], "at", i, "expected", pixelValues[i%4]);
return true;
}
}
return false;
}
addTest("known pixel value test 1", function(log){
return testKnownPixelValue(1, log);
});
addTest("known pixel value test 10", function(log){
return testKnownPixelValue(10, log);
});
addTest("double readout test", function(log){
var canvas = document.createElement("canvas");
var context = canvas.getContext("2d");
var imageData = context.getImageData(0, 0, canvas.width, canvas.height);
for (var i = 0; i < imageData.data.length; i += 1){
if (i % 4 !== 3){
imageData.data[i] = Math.floor(256 * Math.random());
}
else {
imageData.data[i] = 255;
}
}
context.putImageData(imageData, 0, 0);
var imageData1 = context.getImageData(0, 0, canvas.width, canvas.height);
var imageData2 = context.getImageData(0, 0, canvas.width, canvas.height);
for (var i = 0; i < imageData2.data.length; i += 1){
if (imageData1.data[i] !== imageData2.data[i]){
log("mismatch at", i, ":",
imageData1.data[i], "(", imageData1.data[i].toString(2), ")",
"!=",
imageData2.data[i], "(", imageData2.data[i].toString(2), ")",
"| original:", imageData.data[i], "(", imageData.data[i].toString(2), ")");
return true;
}
}
return false;
});
</script>
</body> </body>
</html> </html>

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test/detectionTest.js Normal file
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var addTest = (function(){
var stati = [
{className: "notRun", text: "not run"},
{className: "loud", text: "CB detected"},
{className: "stealthy", text: "CB not detected"},
{className: "failed", text: "test failed"}
];
var ul = document.getElementById("tests");
return function addTest(name, func){
var logs = [];
function log(){
logs.push(Array.prototype.slice.call(arguments).join(" "));
}
var status = 0;
try {
status = func(log)? 1: 2;
}
catch (e){
console.log(e);
status = 3;
}
var li = document.createElement("li");
li.className = stati[status].className;
var nameNode = document.createElement("span");
nameNode.className = "name";
nameNode.textContent = name;
nameNode.title = func.toString();
li.appendChild(nameNode);
li.appendChild(document.createTextNode(": "));
var statusNode = document.createElement("span");
statusNode.className = "status";
statusNode.textContent = stati[status].text;
statusNode.title = logs.join("\n");
li.appendChild(statusNode);
ul.appendChild(li);
}
}());
addTest("function length", function(log){
if (CanvasRenderingContext2D.prototype.getImageData.length !== 4){
log("expected 4 parameters for getImageData - got", CanvasRenderingContext2D.prototype.getImageData.length);
return true;
}
else {
return false;
}
});
addTest("function code", function(log){
if (!CanvasRenderingContext2D.prototype.getImageData.toString().match(/^\s*function getImageData\s*\(\)\s*\{\s*\[native code\]\s*\}\s*$/)){
log("unexpected function code:", CanvasRenderingContext2D.prototype.getImageData.toString());
return true;
}
else {
return false;
}
});
addTest("function name", function(){return CanvasRenderingContext2D.prototype.getImageData.name !== "getImageData"});
addTest("error provocation 1", function(log){
var canvas = document.createElement('canvas');
var ctx = canvas.getContext("2d");
var canvasBlocker = false;
try{
ctx.getImageData(0, 0, 0, 0);
}
catch (err){
try {
log(err.name);
log(err.toString());
}
catch (e){
canvasBlocker = true;
}
}
return canvasBlocker;
});
addTest("error provocation 2", function(log){
var canvas = document.createElement('canvas');
canvas.width = 0;
var ctx = canvas.getContext("2d");
var canvasBlocker = false;
try{
ctx.getImageData(0, 0, 1, 1);
log("no error provoked");
}
catch (err){
try {
log(err.name);
log(err.toString());
}
catch (e){
canvasBlocker = true;
}
}
return canvasBlocker;
});
addTest("error provocation 3", function(log){
var canvasBlocker = false;
try{
CanvasRenderingContext2D.prototype.getImageData.apply(undefined, [0, 0, 1, 1]);
}
catch (err){
try {
log(err.name);
log(err.toString());
}
catch (e){
canvasBlocker = true;
}
}
return canvasBlocker;
});
function testKnownPixelValue(size, log){
var canvas = document.createElement("canvas");
canvas.height = size;
canvas.width = size;
var context = canvas.getContext("2d");
context.fillStyle = "rgba(0, 127, 255, 1)";
var pixelValues = [0, 127, 255, 255];
context.fillRect(0, 0, canvas.width, canvas.height);
var p = context.getImageData(0, 0, canvas.width, canvas.height).data;
for (var i = 0; i < p.length; i += 1){
if (p[i] !== pixelValues[i%4]){
log("wrong value", p[i], "at", i, "expected", pixelValues[i%4]);
return true;
}
}
return false;
}
addTest("known pixel value test 1", function(log){
return testKnownPixelValue(1, log);
});
addTest("known pixel value test 10", function(log){
return testKnownPixelValue(10, log);
});
addTest("double readout test", function(log){
var canvas = document.createElement("canvas");
var context = canvas.getContext("2d");
var imageData = context.getImageData(0, 0, canvas.width, canvas.height);
for (var i = 0; i < imageData.data.length; i += 1){
if (i % 4 !== 3){
imageData.data[i] = Math.floor(256 * Math.random());
}
else {
imageData.data[i] = 255;
}
}
context.putImageData(imageData, 0, 0);
var imageData1 = context.getImageData(0, 0, canvas.width, canvas.height);
var imageData2 = context.getImageData(0, 0, canvas.width, canvas.height);
for (var i = 0; i < imageData2.data.length; i += 1){
if (imageData1.data[i] !== imageData2.data[i]){
log("mismatch at", i, ":",
imageData1.data[i], "(", imageData1.data[i].toString(2), ")",
"!=",
imageData2.data[i], "(", imageData2.data[i].toString(2), ")",
"| original:", imageData.data[i], "(", imageData.data[i].toString(2), ")"
);
return true;
}
}
return false;
});
addTest("readout - in - out test", function(log){
var canvas = document.createElement("canvas");
var context = canvas.getContext("2d");
var imageData = context.getImageData(0, 0, canvas.width, canvas.height);
for (var i = 0; i < imageData.data.length; i += 1){
if (i % 4 !== 3){
imageData.data[i] = Math.floor(256 * Math.random());
}
else {
imageData.data[i] = 255;
}
}
context.putImageData(imageData, 0, 0);
var imageData1 = context.getImageData(0, 0, canvas.width, canvas.height);
var canvas2 = document.createElement("canvas");
var context2 = canvas2.getContext("2d");
context2.putImageData(imageData1, 0, 0);
var imageData2 = context2.getImageData(0, 0, canvas.width, canvas.height);
for (var i = 0; i < imageData2.data.length; i += 1){
if (imageData1.data[i] !== imageData2.data[i]){
log("mismatch at", i, ":",
imageData1.data[i], "(", imageData1.data[i].toString(2), ")",
"!=",
imageData2.data[i], "(", imageData2.data[i].toString(2), ")"
);
return true;
}
}
return false;
});

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console.log("first possible call");

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test/index.html Normal file
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<!DOCTYPE html>
<html>
<head>
<title>Test pages</title>
</head>
<body>
<h1>Test pages for CanvasBlocker</h1>
<ul>
<li><a href="test.html">Fingerprinting test</a></li>
<li><a href="detectionTest.html">Detection test</a></li>
<li><a href="performanceTest.html">Performance test</a></li>
<li><a href="webGL-Test.html">Support for webGL</a></li>
</ul>
</body></html>

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@ -1,137 +1,12 @@
<!DOCTYPE html> <!DOCTYPE html>
<script>console.log("first possible call");</script>
<html> <html>
<head> <head>
<title>Performance test</title> <title>Performance test</title>
</head> </head>
<body> <body>
<h1>Performance test</h1>
Tests the canvas readout performance.
<div id="log"> <div id="log">
</div> </div>
<script> <script src="performanceTest.js"></script>
var createLog = function(){
var div = document.getElementById("log");
return function createLog(){
var logDiv = document.createElement("div");
logDiv.className = "log";
div.appendChild(logDiv);
return function createLine(str){
var logLine = document.createElement("div");
logLine.className = "logLine";
logDiv.appendChild(logLine);
logLine.textContent = str;
return function updateLine(str){
logLine.textContent = str;
};
};
};
}();
var performTest = function(){
return function performTest(name, func, innerRunLength, outerRunLength){
var log = createLog();
log("test " + name);
var line = log("starting");
var time = 0;
var time2 = 0;
var min = Number.POSITIVE_INFINITY;
var max = 0;
var outerI = 0;
function run(){
for (var i = 0; i < innerRunLength; i += 1){
func.prepare();
var start = performance.now();
func.test();
var end = performance.now();
var duration = end - start;
min = Math.min(min, duration);
max = Math.max(max, duration);
time2 += duration * duration;
time += duration;
}
outerI += 1;
var totalRunI = outerI * innerRunLength;
line(
"finished run " + totalRunI + " from " + (innerRunLength * outerRunLength) +
" -> average: " + (time / totalRunI).toFixed(2) + "ms" +
"(min: " + min.toFixed(2) + "ms, max: " + max.toFixed(2) + "ms)"
);
if (outerI < outerRunLength){
window.setTimeout(run, 10);
}
else {
log("finished");
}
}
window.setTimeout(run, 10);
};
}();
function draw(canvas){
canvas.setAttribute("width", 220);
canvas.setAttribute("height", 30);
var fp_text = "BrowserLeaks,com <canvas> 10";
var ctx = canvas.getContext('2d');
ctx.textBaseline = "top";
ctx.font = "14px 'Arial'";
ctx.textBaseline = "alphabetic";
ctx.fillStyle = "#f60";
ctx.fillRect(125, 1, 62, 20);
ctx.fillStyle = "#069";
ctx.fillText(fp_text, 2, 15);
ctx.fillStyle = "rgba(102, 204, 0, 07)";
ctx.fillText(fp_text, 4, 17);
return ctx;
}
var fingerprintTest = function(){
var canvas;
return {
prepare: function(){
// create window canvas
canvas = document.createElement('canvas');
// draw image in window canvas
draw(canvas);
},
test: function fingerprintTest(){
return canvas.toDataURL();
}
};
}();
var randomImageTest = function(){
var canvas;
return {
prepare: function(){
canvas = document.createElement("canvas");
canvas.width = 1000;
canvas.height = 100;
var imageData = new ImageData(canvas.width, canvas.height);
var data = imageData.data;
for (var i = 0; i < data.length; i += 4){
data[i + 0] = Math.floor(256 * Math.random());
data[i + 1] = Math.floor(256 * Math.random());
data[i + 2] = Math.floor(256 * Math.random());
data[i + 3] = 255;
}
canvas.getContext("2d").putImageData(imageData, 0, 0);
},
test: function randomImageTest(){
return canvas.toDataURL();
}
};
}();
performTest("fingerprinting", fingerprintTest, 10, 100);
performTest("big random image", randomImageTest, 10, 10);
</script>
</body></html> </body></html>

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test/performanceTest.js Normal file
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var createLog = function(){
var div = document.getElementById("log");
return function createLog(){
var logDiv = document.createElement("div");
logDiv.className = "log";
div.appendChild(logDiv);
return function createLine(str){
var logLine = document.createElement("div");
logLine.className = "logLine";
logDiv.appendChild(logLine);
logLine.textContent = str;
return function updateLine(str){
logLine.textContent = str;
};
};
};
}();
var performTest = function(){
return function performTest(name, func, innerRunLength, outerRunLength){
var log = createLog();
log("test " + name);
var line = log("starting");
var time = 0;
var time2 = 0;
var min = Number.POSITIVE_INFINITY;
var max = 0;
var outerI = 0;
function run(){
for (var i = 0; i < innerRunLength; i += 1){
func.prepare();
var start = performance.now();
func.test();
var end = performance.now();
var duration = end - start;
min = Math.min(min, duration);
max = Math.max(max, duration);
time2 += duration * duration;
time += duration;
}
outerI += 1;
var totalRunI = outerI * innerRunLength;
line(
"finished run " + totalRunI + " from " + (innerRunLength * outerRunLength) +
" -> average: " + (time / totalRunI).toFixed(2) + "ms" +
"(min: " + min.toFixed(2) + "ms, max: " + max.toFixed(2) + "ms)"
);
if (outerI < outerRunLength){
window.setTimeout(run, 10);
}
else {
log("finished");
}
}
window.setTimeout(run, 10);
};
}();
function draw(canvas){
canvas.setAttribute("width", 220);
canvas.setAttribute("height", 30);
var fp_text = "BrowserLeaks,com <canvas> 10";
var ctx = canvas.getContext('2d');
ctx.textBaseline = "top";
ctx.font = "14px 'Arial'";
ctx.textBaseline = "alphabetic";
ctx.fillStyle = "#f60";
ctx.fillRect(125, 1, 62, 20);
ctx.fillStyle = "#069";
ctx.fillText(fp_text, 2, 15);
ctx.fillStyle = "rgba(102, 204, 0, 07)";
ctx.fillText(fp_text, 4, 17);
return ctx;
}
var fingerprintTest = function(){
var canvas;
return {
prepare: function(){
// create window canvas
canvas = document.createElement('canvas');
// draw image in window canvas
draw(canvas);
},
test: function fingerprintTest(){
return canvas.toDataURL();
}
};
}();
var randomImageTest = function(){
var canvas;
return {
prepare: function(){
canvas = document.createElement("canvas");
canvas.width = 1000;
canvas.height = 100;
var imageData = new ImageData(canvas.width, canvas.height);
var data = imageData.data;
for (var i = 0; i < data.length; i += 4){
data[i + 0] = Math.floor(256 * Math.random());
data[i + 1] = Math.floor(256 * Math.random());
data[i + 2] = Math.floor(256 * Math.random());
data[i + 3] = 255;
}
canvas.getContext("2d").putImageData(imageData, 0, 0);
},
test: function randomImageTest(){
return canvas.toDataURL();
}
};
}();
performTest("fingerprinting", fingerprintTest, 10, 100);
performTest("big random image", randomImageTest, 10, 10);

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var main = require("./main");
exports["test main"] = function(assert) {
assert.pass("Unit test running!");
};
exports["test main async"] = function(assert, done) {
assert.pass("async Unit test running!");
done();
};
require("sdk/test").run(exports);

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<!DOCTYPE html> <!DOCTYPE html>
<script>console.log("first possible call");</script> <script src="firstPossibleCall.js"></script>
<html> <html>
<head> <head>
<title>Test</title> <title>Test</title>
@ -18,76 +18,5 @@
<iframe sandbox="allow-same-origin" style="display:none"></iframe> <iframe sandbox="allow-same-origin" style="display:none"></iframe>
<button>refresh</button> <button>refresh</button>
</div> </div>
<script> <script src="test.js"></script>
(function(){
function show(container, url){
container.querySelector(".display").src = url;
var buffer = new TextEncoder("utf-8").encode(url);
crypto.subtle.digest("SHA-256", buffer).then(function(hash){
var chunks = [];
(new Uint32Array(hash)).forEach(function(num){
chunks.push(num.toString(16));
});
container.querySelector(".hash").textContent = chunks.map(function(chunk){
return "0".repeat(8 - chunk.length) + chunk;
}).join("");
});
}
if (location.search !== "?notInitial"){
show(document.getElementById("top"), topTest());
show(document.getElementById("iframe"), iframeTest());
}
document.querySelector("#top button").addEventListener("click", function(){show(document.getElementById("top"), topTest());});
document.querySelector("#iframe button").addEventListener("click", function(){show(document.getElementById("iframe"), iframeTest());});
}());
function draw(canvas){
canvas.setAttribute("width", 220);
canvas.setAttribute("height", 30);
var fp_text = "BrowserLeaks,com <canvas> 10";
var ctx = canvas.getContext('2d');
ctx.textBaseline = "top";
ctx.font = "14px 'Arial'";
ctx.textBaseline = "alphabetic";
ctx.fillStyle = "#f60";
ctx.fillRect(125, 1, 62, 20);
ctx.fillStyle = "#069";
ctx.fillText(fp_text, 2, 15);
ctx.fillStyle = "rgba(102, 204, 0, 07)";
ctx.fillText(fp_text, 4, 17);
return ctx;
}
function topTest(){
// create window canvas
var canvas = document.createElement('canvas');
// draw image in window canvas
draw(canvas);
return canvas.toDataURL();
}
function iframeTest(){
// create window canvas
var canvas = document.createElement('canvas');
// draw image in window canvas
draw(canvas);
// create iframe canvas and ctx
var iframe_canvas = document.querySelector("#iframe iframe").contentDocument.createElement('canvas');
iframe_canvas.setAttribute("width", 220);
iframe_canvas.setAttribute("height", 30);
var iframe_ctx = iframe_canvas.getContext('2d');
// copy image from window canvas to iframe ctx
iframe_ctx.drawImage(canvas, 0, 0);
return iframe_canvas.toDataURL();
}
</script>
</body></html> </body></html>

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(function(){
function show(container, url){
container.querySelector(".display").src = url;
var buffer = new TextEncoder("utf-8").encode(url);
crypto.subtle.digest("SHA-256", buffer).then(function(hash){
var chunks = [];
(new Uint32Array(hash)).forEach(function(num){
chunks.push(num.toString(16));
});
container.querySelector(".hash").textContent = chunks.map(function(chunk){
return "0".repeat(8 - chunk.length) + chunk;
}).join("");
});
}
if (location.search !== "?notInitial"){
show(document.getElementById("top"), topTest());
show(document.getElementById("iframe"), iframeTest());
}
document.querySelector("#top button").addEventListener("click", function(){show(document.getElementById("top"), topTest());});
document.querySelector("#iframe button").addEventListener("click", function(){show(document.getElementById("iframe"), iframeTest());});
}());
function draw(canvas){
canvas.setAttribute("width", 220);
canvas.setAttribute("height", 30);
var fp_text = "BrowserLeaks,com <canvas> 10";
var ctx = canvas.getContext('2d');
ctx.textBaseline = "top";
ctx.font = "14px 'Arial'";
ctx.textBaseline = "alphabetic";
ctx.fillStyle = "#f60";
ctx.fillRect(125, 1, 62, 20);
ctx.fillStyle = "#069";
ctx.fillText(fp_text, 2, 15);
ctx.fillStyle = "rgba(102, 204, 0, 07)";
ctx.fillText(fp_text, 4, 17);
return ctx;
}
function topTest(){
// create window canvas
var canvas = document.createElement('canvas');
// draw image in window canvas
draw(canvas);
return canvas.toDataURL();
}
function iframeTest(){
// create window canvas
var canvas = document.createElement('canvas');
// draw image in window canvas
draw(canvas);
// create iframe canvas and ctx
var iframe_canvas = document.querySelector("#iframe iframe").contentDocument.createElement('canvas');
iframe_canvas.setAttribute("width", 220);
iframe_canvas.setAttribute("height", 30);
var iframe_ctx = iframe_canvas.getContext('2d');
// copy image from window canvas to iframe ctx
iframe_ctx.drawImage(canvas, 0, 0);
return iframe_canvas.toDataURL();
}

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<!DOCTYPE html> <!DOCTYPE html>
<html> <html>
<head> <head>
<title>Test</title> <title>webGL test</title>
</head> </head>
<body> <body>
<canvas id="canvas" width="10" height="10"></canvas> <h1>webGL test</h1>
<span id="output"></span> Checks if the addon also supports webGL.
<script> <div id="output"></div>
(function(){ <script src="webGL-Test.js"></script>
var canvas = document.getElementById('canvas');
var gl = canvas.getContext('webgl');
var pixels = new Uint8Array(gl.drawingBufferWidth * gl.drawingBufferHeight * 4);
gl.readPixels(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
var values = [];
for (var i = 0; i < pixels.length; i += 1){
values[pixels[i]] = (values[pixels[i]] || 0) + 1;
}
document.getElementById("output").textContent = JSON.stringify(values);
}());
</script>
</body></html> </body></html>

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test/webGL-Test.js Normal file
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(function(){
var canvas = document.createElement('canvas');
canvas.width = 11;
canvas.height = 13;
var gl = canvas.getContext('webgl');
// paint it completely black
gl.clearColor(0, 0, 0, 1);
gl.clear(gl.COLOR_BUFFER_BIT);
var pixels = new Uint8Array(gl.drawingBufferWidth * gl.drawingBufferHeight * 4);
gl.readPixels(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
var values = {};
for (var i = 0; i < pixels.length; i += 1){
values[pixels[i]] = (values[pixels[i]] || 0) + 1;
}
document.getElementById("output").textContent = JSON.stringify(values);
}());