81 lines
2.4 KiB
TypeScript
81 lines
2.4 KiB
TypeScript
module es {
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export class MathHelper {
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public static readonly Epsilon: number = 0.00001;
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public static readonly Rad2Deg = 57.29578;
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public static readonly Deg2Rad = 0.0174532924;
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/**
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* 将弧度转换成角度。
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* @param radians 用弧度表示的角
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*/
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public static toDegrees(radians: number){
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return radians * 57.295779513082320876798154814105;
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}
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/**
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* 将角度转换为弧度
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* @param degrees
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*/
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public static toRadians(degrees: number){
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return degrees * 0.017453292519943295769236907684886;
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}
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/**
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* mapps值(在leftMin - leftMax范围内)到rightMin - rightMax范围内的值
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* @param value
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* @param leftMin
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* @param leftMax
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* @param rightMin
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* @param rightMax
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*/
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public static map(value: number, leftMin: number, leftMax: number, rightMin: number, rightMax: number){
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return rightMin + (value - leftMin) * (rightMax - rightMin) / (leftMax - leftMin);
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}
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public static lerp(value1: number, value2: number, amount: number){
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return value1 + (value2 - value1) * amount;
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}
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public static clamp(value: number, min: number, max: number){
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if (value < min)
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return min;
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if (value > max)
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return max;
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return value;
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}
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public static pointOnCirlce(circleCenter: Vector2, radius: number, angleInDegrees: number){
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let radians = MathHelper.toRadians(angleInDegrees);
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return new Vector2(Math.cos(radians) * radians + circleCenter.x, Math.sin(radians) * radians + circleCenter.y);
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}
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/**
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* 如果值为偶数，返回true
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* @param value
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*/
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public static isEven(value: number){
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return value % 2 == 0;
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}
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/**
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* 数值限定在0-1之间
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* @param value
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*/
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public static clamp01(value: number){
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if (value < 0)
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return 0;
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if (value > 1)
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return 1;
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return value;
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}
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public static angleBetweenVectors(from: Vector2, to: Vector2){
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return Math.atan2(to.y - from.y, to.x - from.x);
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}
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}
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}
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