mirror of
https://github.com/photonstorm/phaser
synced 2024-12-24 03:53:28 +00:00
25 lines
348 B
JavaScript
25 lines
348 B
JavaScript
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let vec2 = Float32Array;
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export default function (a, dst = new vec2(2)) {
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const x = a[0];
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const y = a[1];
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const lsq = x * x + y * y;
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if (lsq > 0)
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{
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const lr = 1 / Math.sqrt(lsq);
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dst[0] = x * lr;
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dst[1] = y * lr;
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}
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else
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{
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dst[0] = 0;
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dst[1] = 0;
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}
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return dst;
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}
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