Math

Math

Pure stateless math utilities. All functions are named exports.

import * as math from './src/math.js';
// or selectively:
import { clamp, lerp, random } from './src/math.js';

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Scalar

math.abs(x)                  // Math.abs
math.sign(x)                 // Math.sign
math.signNonzero(x)          // 1 if x >= 0, else -1
math.min(a, b)
math.max(a, b)
math.clamp(x, lo, hi)        // clamp(15, 0, 10) → 10
math.minmax(a, b)            // → { min, max }
math.mod(x, m)               // always non-negative modulo
math.wrap(x, lo, hi)         // wrap x into [lo, hi)
math.ceilDiv(a, b)           // Math.ceil(a / b)
math.divmod(a, b)            // → { quot, rem }
math.mulDiv(a, b, c)         // (a * b) / c
math.round(x)
math.sqrt(x)
math.pow(base, exp)
math.log2(x)

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Trigonometry (degrees)

math.sin(deg)       // Math.sin with degree input
math.cos(deg)
math.atan2(y, x)    // returns degrees

---

Aggregation

math.average(1, 2, 3, 4)     // 2.5
math.sum3(a, b, c)
math.factorial(n)             // throws RangeError for negative or non-integer
math.gcd(a, b)
math.lcm(a, b)

---

Random

math.random(1, 6)             // integer in [min, max] inclusive

math.weightedRandom([
  { value: 'common', weight: 70 },
  { value: 'rare',   weight: 25 },
  { value: 'epic',   weight: 5  },
])
// → one of the values, selected by weight
// throws RangeError if array is empty or all weights are 0

---

Interpolation / mapping

math.lerp(a, b, t)                          // linear interpolation
math.lerpClamped(a, b, t)                   // t clamped to [0, 1]
math.mapRange(x, inMin, inMax, outMin, outMax)
math.isBetween(x, lo, hi)                   // → boolean, inclusive

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Distance

math.distance2d(x1, y1, x2, y2)
math.distance3d(x1, y1, z1, x2, y2, z2)

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3D Vectors

Vectors are plain [x, y, z] arrays.

math.vec.add(a, b)
math.vec.sub(a, b)
math.vec.dot(a, b)
math.vec.cross(a, b)
math.vec.normalize(v)
math.vec.angleBetween(a, b)   // degrees between two vectors