// Provides a simple 3D vector class. Vector operations can be done using member functions, which return new vectors, or static functions, which reuse existing vectors to avoid generating garbage. // original code by https://evanw.github.io/lightgl.js/docs/vector.html (function() { function Vector(x, y, z) { this.x = x || 0; this.y = y || 0; this.z = z || 0; } Vector.prototype = { negative: function() { return new Vector(-this.x, -this.y, -this.z); }, add: function(v) { if (v instanceof Vector) return new Vector(this.x + v.x, this.y + v.y, this.z + v.z); else return new Vector(this.x + v, this.y + v, this.z + v); }, subtract: function(v) { if (v instanceof Vector) return new Vector(this.x - v.x, this.y - v.y, this.z - v.z); else return new Vector(this.x - v, this.y - v, this.z - v); }, multiply: function(v) { if (v instanceof Vector) return new Vector(this.x * v.x, this.y * v.y, this.z * v.z); else return new Vector(this.x * v, this.y * v, this.z * v); }, divide: function(v) { if (v instanceof Vector) return new Vector(this.x / v.x, this.y / v.y, this.z / v.z); else return new Vector(this.x / v, this.y / v, this.z / v); }, equals: function(v) { return this.x == v.x && this.y == v.y && this.z == v.z; }, dot: function(v) { return this.x * v.x + this.y * v.y + this.z * v.z; }, cross: function(v) { return new Vector( this.y * v.z - this.z * v.y, this.z * v.x - this.x * v.z, this.x * v.y - this.y * v.x ); }, length: function() { return Math.sqrt(this.dot(this)); }, unit: function() { return this.divide(this.length()); }, min: function() { return Math.min(Math.min(this.x, this.y), this.z); }, max: function() { return Math.max(Math.max(this.x, this.y), this.z); }, toAngles: function() { return { theta: Math.atan2(this.z, this.x), phi: Math.asin(this.y / this.length()) }; }, angleTo: function(a) { return Math.acos(this.dot(a) / (this.length() * a.length())); }, toArray: function(n) { return [this.x, this.y, this.z].slice(0, n || 3); }, clone: function() { return new Vector(this.x, this.y, this.z); }, init: function(x, y, z) { this.x = x; this.y = y; this.z = z; return this; }, noZ: function() { this.z = 0; return this; } }; Vector.negative = function(a, b) { b.x = -a.x; b.y = -a.y; b.z = -a.z; return b; }; Vector.add = function(a, b, c) { if (b instanceof Vector) { c.x = a.x + b.x; c.y = a.y + b.y; c.z = a.z + b.z; } else { c.x = a.x + b; c.y = a.y + b; c.z = a.z + b; } return c; }; Vector.subtract = function(a, b, c) { if (b instanceof Vector) { c.x = a.x - b.x; c.y = a.y - b.y; c.z = a.z - b.z; } else { c.x = a.x - b; c.y = a.y - b; c.z = a.z - b; } return c; }; Vector.multiply = function(a, b, c) { if (b instanceof Vector) { c.x = a.x * b.x; c.y = a.y * b.y; c.z = a.z * b.z; } else { c.x = a.x * b; c.y = a.y * b; c.z = a.z * b; } return c; }; Vector.divide = function(a, b, c) { if (b instanceof Vector) { c.x = a.x / b.x; c.y = a.y / b.y; c.z = a.z / b.z; } else { c.x = a.x / b; c.y = a.y / b; c.z = a.z / b; } return c; }; Vector.cross = function(a, b, c) { c.x = a.y * b.z - a.z * b.y; c.y = a.z * b.x - a.x * b.z; c.z = a.x * b.y - a.y * b.x; return c; }; Vector.unit = function(a, b) { var length = a.length(); b.x = a.x / length; b.y = a.y / length; b.z = a.z / length; return b; }; Vector.fromAngles = function(theta, phi) { return new Vector(Math.cos(theta) * Math.cos(phi), Math.sin(phi), Math.sin(theta) * Math.cos(phi)); }; Vector.randomDirection = function() { return Vector.fromAngles(Math.random() * Math.PI * 2, Math.asin(Math.random() * 2 - 1)); }; Vector.min = function(a, b) { return new Vector(Math.min(a.x, b.x), Math.min(a.y, b.y), Math.min(a.z, b.z)); }; Vector.max = function(a, b) { return new Vector(Math.max(a.x, b.x), Math.max(a.y, b.y), Math.max(a.z, b.z)); }; Vector.lerp = function(a, b, fraction) { return b.subtract(a).multiply(fraction).add(a); }; Vector.fromArray = function(a) { return new Vector(a[0], a[1], a[2]); }; Vector.angleBetween = function(a, b) { return a.angleTo(b); }; window.Vector = Vector; })();