34 lines
1.1 KiB
JavaScript
34 lines
1.1 KiB
JavaScript
(function(){
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"use strict";
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["webgl", "webgl2"].forEach(function(context, index){
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var output = document.createElement("div");
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document.getElementById("output").appendChild(output);
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try {
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var canvas = document.createElement("canvas");
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canvas.width = 11;
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canvas.height = 13;
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var gl = canvas.getContext(context) || canvas.getContext("experimental-" + context);
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// paint it completely black
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gl.clearColor(index * 0.25, index * 0.25, index * 0.25, 1);
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gl.clear(gl.COLOR_BUFFER_BIT);
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var pixels = new Uint8Array(gl.drawingBufferWidth * gl.drawingBufferHeight * 4);
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gl.readPixels(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
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var values = {};
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var max = 0;
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for (var i = 0; i < pixels.length; i += 1){
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values[pixels[i]] = (values[pixels[i]] || 0) + 1;
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max = Math.max(max, values[pixels[i]]);
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}
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output.textContent = context + ": " + (max !== 3 * values[255]? "": "not ") + "faked";
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output.title = JSON.stringify(values);
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}
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catch (e){
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output.textContent = context + ": ERROR";
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output.title = e;
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}
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});
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}()); |