@brad_promptnow/vec3

Small, dependency-free 3D vector math for TypeScript and JavaScript.

• Plain objects ({ x, y, z }), no classes
• Full TypeScript types included
• Every function returns a new value and never modifies its inputs

Install

npm install @brad_promptnow/vec3

Quick start

import { v3_add, v3_cross, v3_length } from "@brad_promptnow/vec3";
import type { V3 } from "@brad_promptnow/vec3";

const a: V3 = { x: 1, y: 0, z: 0 };
const b: V3 = { x: 0, y: 1, z: 0 };

v3_add(a, b);    // { x: 1, y: 1, z: 0 }
v3_cross(a, b);  // { x: 0, y: 0, z: 1 }
v3_length({ x: 2, y: 3, z: 6 }); // 7

CommonJS also works:

const { v3_add } = require("@brad_promptnow/vec3");

API

Type

type V3 = { x: number; y: number; z: number };

Functions

| Function | Returns | Description | |---|---|---| | v3_add(a, b) | V3 | a + b | | v3_sub(a, b) | V3 | a - b | | v3_mul(a, b) | V3 | Component-wise multiply: (a.x*b.x, a.y*b.y, a.z*b.z) | | v3_scale(a, s) | V3 | Multiply every component by the number s | | v3_dot(a, b) | number | Dot product | | v3_cross(a, b) | V3 | Cross product, perpendicular to both inputs | | v3_length(a) | number | Length (magnitude) of the vector |

Notes

• Dot product is positive when the vectors point the same way, 0 when perpendicular, and negative when opposite.
• Cross product is order-sensitive: v3_cross(a, b) points the opposite way from v3_cross(b, a).
• v3_mul vs v3_scale: v3_mul takes two vectors and multiplies each axis separately. v3_scale takes a vector and a single number.

Examples

import { v3_sub, v3_scale, v3_dot } from "@brad_promptnow/vec3";

// direction from point p to point q
const dir = v3_sub({ x: 4, y: 5, z: 6 }, { x: 1, y: 2, z: 3 }); // { x: 3, y: 3, z: 3 }

// move a position by velocity * time
const next = v3_scale({ x: 1, y: 0, z: 0 }, 2.5); // { x: 2.5, y: 0, z: 0 }

// are two vectors perpendicular?
v3_dot({ x: 1, y: 0, z: 0 }, { x: 0, y: 1, z: 0 }) === 0; // true

Development

npm install
npm run build   # compiles src/ to dist/
npm pack        # creates a .tgz to test locally

Releasing a new version:

npm version patch   # or minor / major
npm run build
npm publish --access public

License

ISC