mirror of
https://github.com/kkapsner/CanvasBlocker
synced 2024-12-22 12:50:36 +01:00
22 lines
661 B
HTML
22 lines
661 B
HTML
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<!DOCTYPE html>
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<html>
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<head>
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<title>Test</title>
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</head>
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<body>
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<canvas id="canvas" width="10" height="10"></canvas>
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<span id="output"></span>
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<script>
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(function(){
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var canvas = document.getElementById('canvas');
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var gl = canvas.getContext('webgl');
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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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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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}
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document.getElementById("output").textContent = JSON.stringify(values);
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}());
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</script>
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</body></html>
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