Linearly is a library providing a collection of utility functions that relates to linear algebra and graphics programming. It is deeply inspired by glMatrix, but adopts functional programming manner and immutable data structure.

import {mat2d, vec3} from 'linearly'

// Unlike glMatrix, you don't need to specify a receiver matrix as the first argument.
const p0 = vec2.add([1, 2], [3, 4])
const p1 = vec2.transformMat2d(p0, mat2d.fromRotation(scalar.rad(45)))

const dir = vec3.normalize([2, 1, 3])
const b = vec3.cross(dir, [0, 1, 0])
const c = vec3.scale(out, 3)

// As the values of Linearly are plain 1D arrays,
// you can initialize a vector by either way.
const a: vec2 = [1, 2]
const b = vec2.of(1, 2)

// But since vector and matrix are immutable
// and annotated with readonly flags,
// a mutation such as below are handled as an error in TypeScript.
a[0] = 3
// ^
// Cannot assign to '0' because it is a read-only property.

// Some constants such as mat2.identity are also readonly
// and defined as frozen array (applied Object.freeze).
// You can use `clone` to mutate them.
const m = mat2d.clone(mat2d.ident)
m[4] *= 2.0
m[5] = -4.5

In addition to functions that can be found on glMatrix docs, the library also provides some useful functions. For example:

• GLSL - step, mix, smoothstep
• Vex in Houdini - fit, efit, invlerp, degrees, radians
• Unity - inverseLerp, oneMinus

Modules

The names of modules are derived from glMatrix.

• scalar: A single number
• mat2: 2D linear transformation (rotation, scaling, skewing)
• mat2d: 2D affine transformation, omitting redundant third rows, which is always set to [0, 0, 1] (translation, rotation, scaling, skewing)
• mat3: 2D affine transformation (translation, rotation, scaling, skewing)
• mat4: 3D transformation
• quat: 3D rotation