mirror of
https://github.com/photonstorm/phaser
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33 lines
754 B
JavaScript
33 lines
754 B
JavaScript
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/**
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* Get the X component of a point on the curve based on the `t` (time) value, which must be between 0 and 1.
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*
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* @param {number} [t=0] - The time value along the curve from which to extract a point. This is a value between 0 and 1, where 0 represents the start of the curve and 1 the end.
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* @return {number} The X component of a point on the curve based on the `t` (time) value.
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*/
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var GetX = function (curve, t)
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{
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if (t === undefined)
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{
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t = 0;
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}
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else
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{
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if (t < 0)
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{
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t = 0;
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}
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if (t > 1)
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{
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t = 1;
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}
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}
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var t2 = t * t;
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var t3 = t * t2;
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return (t3 * curve._ax + t2 * curve._bx + t * curve._v1x + curve._p1x);
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};
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module.exports = GetX;
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