Math

Math objects carry values only. They have no Game owner or native resource lifetime, so create and reuse them freely.

Vectors

import { Vector2D, Vec3 } from '@bornengine/engine';
import type { Vector2DLike } from '@bornengine/engine';
const start = new Vec3(0, 1, 0);
const velocity = new Vec3(4, 0, -2);
const next = start.add(velocity.scale(0.016));
const direction = next.normalized();
const screen = new Vector2D(640, 360);
const clamped = Vector2D.clamp(screen, Vector2D.zero(), new Vector2D(800, 600));
const movement = Vector2D.moveTowards(screen, Vector2D.zero(), 12);
const savedPosition: Vector2DLike = { x: screen.x, y: screen.y };

Vector2D is the value class for 2D coordinates. Arithmetic helpers return new vectors; set and copy mutate the current instance. It includes clamp, clampMagnitude, dot, distance, lerp, moveTowards, reflect, project, and angle helpers. Instance operations such as add, subtract, and scale return new vectors.

Vector2D.up() is positive Y, and angle helpers return degrees. rotate takes radians. 2D APIs also accept Vector2DLike ({ x, y }) at data boundaries, including JSON. Use new Vector2D(x, y) when you want math methods; JSON serialization writes only x and y.

Transforms

Quat represents rotation, while Matrix4 provides composition and view/projection helpers. Angles in user-facing APIs are degrees unless a specific method states otherwise.

import { Matrix4, Quat, Vec3 } from '@bornengine/engine';
const rotation = Quat.fromEuler(0, 45, 0);
const modelMatrix = rotation.toMatrix().translated(new Vec3(2, 0, -4));
const view = Matrix4.lookAt(new Vec3(0, 2, 5), new Vec3(0, 0, 0), new Vec3(0, 1, 0));
const combined = view.multiply(modelMatrix);
const anotherCombination = Matrix4.multiplyMatrices(view, modelMatrix);

Use matrix.multiply(other) when composing from an existing matrix, or Matrix4.multiplyMatrices(a, b) when calling the operation without a receiver.

Intersections

Collision helpers are static because they operate on values rather than owned runtime state.

import { Collision } from '@bornengine/engine';
const hit = Collision.checkSpheres({ x: 0, y: 0, z: 0 }, 1, { x: 1, y: 0, z: 0 }, 1);
const visible = Collision.isBoxInFrustum(bounds, frustumPlanes);

Collision includes 2D rectangles/circles, rays, triangles, bounds, and frustum checks. See the shapes and physics pages for renderer or simulation-owned collision objects.