bump.ts

A collision detection library for TypeScript. Ported from bump.lua.

bump.ts is a collision-detection library for axis-aligned rectangles. Its main features are:

• Axis-aligned bounding-box (AABB) collisions.
• Tunneling - all items are treated as "bullets". The fact that we only use AABBs allows doing this fast.
• Strives to be fast while being economic in memory
• It's centered on detection, but it also offers some (minimal & basic) collision response
• Can also return the items that touch a point, a segment or a rectangular zone.
• "Gameistic" instead of realistic approach to collision detection.

bump.ts is ideal for:

Tile-based games, and games where most entities can be represented as axis-aligned rectangles. Games which require some physics, but not a full realistic simulation - like a platformer. Examples of genres: top-down games (Zelda), Shoot-them-ups, fighting games (Street Fighter), platformers (Super Mario).

bump.ts is not a good match for:

Games that require polygons for the collision detection Games that require highly realistic simulations of physics - things "stacking up", "rolling over slides", etc. Games that require very fast objects colliding reallistically against each other (in bump, being gameistic, objects are moved and collided one at a time) Simulations where the order in which the collisions are resolved isn't known.

Usage example:

import Bump from 'bump-ts'

// The grid cell size can be specified via the initialize method
// By default, the cell size is 64
const world = Bump.newWorld(50)

// Insert two rectangles into bump
world.add('A',   0, 0,    64, 256) // x,y, width, height
world.add('B',   0, -100, 32, 32)

// Try to move B to 0,64. If it collides with A, "slide over it"
const { x, y, collisions } = world.move('B', 0, 64)

// console.logs "Attempted to move to 0,64, but ended up in 0,-32 due to 1 collisions"
if (collisions.length > 0) 
  console.log(`Attempted to move to x:0, y:64, but ended up in x:${x}, y:${y} due to ${collisions.length} collisions`)
else
  console.log("Moved B to 100,100 without collisions")

// console.logs the new coordinates of B: 0, -32, 32, 32
console.log(world.getRect('B'))

// console.logs "Collision with A"
for (const collision of collisions) // If more than one simultaneous collision, they are sorted out by proximity
  console.log(`Collision with ${collision.other}`)

// remove A and B from the world
world.remove(A)
world.remove(B)