38 lines
958 B
HTML
38 lines
958 B
HTML
<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<title>Canvas - Draw Rectangle</title>
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<script type="text/javascript">
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function draw() {
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var canvas = document.getElementById('canvas');
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if (canvas.getContext) {
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var ctx = canvas.getContext('2d');
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var length = 200; // side length of the square
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var num = 8; //number of squares
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var offset = length / 2 / num;
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for (var i = 0; i < num; i++) {
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ctx.fillStyle = (i%2==0)? "black" : "white";
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var x = 10 + offset * i;
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var y = 10 + offset * i;
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ctx.fillRect(x, y, length, length);
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length -= offset * 2;
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var logStr = "x = " + x;
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logStr += ", y = " + y;
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logStr += ", length = " + length;
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console.log(logStr);
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}
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}
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}
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</script>
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</head>
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<body onload="draw();">
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<canvas id="canvas" width="300" height="300" />
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</body>
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</html>
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