23 lines
753 B
HTML
23 lines
753 B
HTML
<!DOCTYPE html>
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<html>
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<head>
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<title>WebGL readPixels() test</title>
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<meta charset="utf-8">
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</head>
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<body>
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<canvas id="test" width="8" height="8"></canvas>
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<script>
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var canvas = document.getElementById("test");
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var gl = canvas.getContext("webgl");
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// Draw a red rectangle
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gl.clearColor(0.0, 0.0, 0.0, 1.0);
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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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pixels[0] = 1;
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gl.readPixels(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
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// First element in pixels array will be 0 if readPixels() call worked, or 1 if readPixels() was blocked.
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document.title = pixels[0];
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</script>
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</body>
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</html>
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