var ArrayCtor = typeof Float32Array === 'undefined' ? Array : Float32Array;
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/**
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* 创建一个向量
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* @param {number} [x=0]
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* @param {number} [y=0]
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* @return {Vector2}
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*/
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function create(x, y) {
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var out = new ArrayCtor(2);
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if (x == null) {
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x = 0;
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}
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if (y == null) {
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y = 0;
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}
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out[0] = x;
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out[1] = y;
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return out;
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}
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/**
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* 复制向量数据
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* @param {Vector2} out
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* @param {Vector2} v
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* @return {Vector2}
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*/
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function copy(out, v) {
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out[0] = v[0];
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out[1] = v[1];
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return out;
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}
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/**
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* 克隆一个向量
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* @param {Vector2} v
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* @return {Vector2}
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*/
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function clone(v) {
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var out = new ArrayCtor(2);
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out[0] = v[0];
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out[1] = v[1];
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return out;
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}
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/**
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* 设置向量的两个项
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* @param {Vector2} out
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* @param {number} a
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* @param {number} b
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* @return {Vector2} 结果
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*/
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function set(out, a, b) {
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out[0] = a;
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out[1] = b;
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return out;
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}
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/**
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* 向量相加
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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*/
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function add(out, v1, v2) {
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out[0] = v1[0] + v2[0];
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out[1] = v1[1] + v2[1];
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return out;
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}
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/**
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* 向量缩放后相加
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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* @param {number} a
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*/
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function scaleAndAdd(out, v1, v2, a) {
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out[0] = v1[0] + v2[0] * a;
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out[1] = v1[1] + v2[1] * a;
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return out;
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}
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/**
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* 向量相减
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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*/
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function sub(out, v1, v2) {
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out[0] = v1[0] - v2[0];
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out[1] = v1[1] - v2[1];
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return out;
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}
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/**
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* 向量长度
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* @param {Vector2} v
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* @return {number}
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*/
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function len(v) {
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return Math.sqrt(lenSquare(v));
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}
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var length = len; // jshint ignore:line
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/**
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* 向量长度平方
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* @param {Vector2} v
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* @return {number}
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*/
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function lenSquare(v) {
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return v[0] * v[0] + v[1] * v[1];
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}
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var lengthSquare = lenSquare;
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/**
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* 向量乘法
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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*/
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function mul(out, v1, v2) {
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out[0] = v1[0] * v2[0];
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out[1] = v1[1] * v2[1];
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return out;
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}
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/**
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* 向量除法
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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*/
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function div(out, v1, v2) {
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out[0] = v1[0] / v2[0];
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out[1] = v1[1] / v2[1];
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return out;
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}
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/**
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* 向量点乘
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* @param {Vector2} v1
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* @param {Vector2} v2
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* @return {number}
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*/
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function dot(v1, v2) {
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return v1[0] * v2[0] + v1[1] * v2[1];
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}
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/**
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* 向量缩放
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* @param {Vector2} out
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* @param {Vector2} v
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* @param {number} s
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*/
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function scale(out, v, s) {
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out[0] = v[0] * s;
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out[1] = v[1] * s;
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return out;
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}
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/**
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* 向量归一化
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* @param {Vector2} out
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* @param {Vector2} v
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*/
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function normalize(out, v) {
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var d = len(v);
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if (d === 0) {
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out[0] = 0;
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out[1] = 0;
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} else {
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out[0] = v[0] / d;
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out[1] = v[1] / d;
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}
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return out;
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}
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/**
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* 计算向量间距离
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* @param {Vector2} v1
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* @param {Vector2} v2
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* @return {number}
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*/
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function distance(v1, v2) {
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return Math.sqrt((v1[0] - v2[0]) * (v1[0] - v2[0]) + (v1[1] - v2[1]) * (v1[1] - v2[1]));
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}
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var dist = distance;
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/**
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* 向量距离平方
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* @param {Vector2} v1
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* @param {Vector2} v2
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* @return {number}
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*/
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function distanceSquare(v1, v2) {
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return (v1[0] - v2[0]) * (v1[0] - v2[0]) + (v1[1] - v2[1]) * (v1[1] - v2[1]);
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}
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var distSquare = distanceSquare;
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/**
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* 求负向量
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* @param {Vector2} out
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* @param {Vector2} v
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*/
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function negate(out, v) {
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out[0] = -v[0];
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out[1] = -v[1];
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return out;
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}
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/**
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* 插值两个点
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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* @param {number} t
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*/
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function lerp(out, v1, v2, t) {
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out[0] = v1[0] + t * (v2[0] - v1[0]);
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out[1] = v1[1] + t * (v2[1] - v1[1]);
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return out;
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}
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/**
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* 矩阵左乘向量
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* @param {Vector2} out
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* @param {Vector2} v
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* @param {Vector2} m
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*/
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function applyTransform(out, v, m) {
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var x = v[0];
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var y = v[1];
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out[0] = m[0] * x + m[2] * y + m[4];
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out[1] = m[1] * x + m[3] * y + m[5];
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return out;
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}
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/**
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* 求两个向量最小值
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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*/
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function min(out, v1, v2) {
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out[0] = Math.min(v1[0], v2[0]);
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out[1] = Math.min(v1[1], v2[1]);
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return out;
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}
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/**
|
* 求两个向量最大值
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* @param {Vector2} out
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* @param {Vector2} v1
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* @param {Vector2} v2
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*/
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function max(out, v1, v2) {
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out[0] = Math.max(v1[0], v2[0]);
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out[1] = Math.max(v1[1], v2[1]);
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return out;
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}
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exports.create = create;
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exports.copy = copy;
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exports.clone = clone;
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exports.set = set;
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exports.add = add;
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exports.scaleAndAdd = scaleAndAdd;
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exports.sub = sub;
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exports.len = len;
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exports.length = length;
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exports.lenSquare = lenSquare;
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exports.lengthSquare = lengthSquare;
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exports.mul = mul;
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exports.div = div;
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exports.dot = dot;
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exports.scale = scale;
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exports.normalize = normalize;
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exports.distance = distance;
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exports.dist = dist;
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exports.distanceSquare = distanceSquare;
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exports.distSquare = distSquare;
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exports.negate = negate;
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exports.lerp = lerp;
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exports.applyTransform = applyTransform;
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exports.min = min;
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exports.max = max;
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