Circular Collision Detection in JavaScript

Collision detection is the core of many games and simulations. It is therefore important to have a simple and efficient collision detection algorithm.

This algorithm uses circles as the basis for colliding elements.

function collision(c1, c2) {
  var dx = c1.x - c2.x;
  var dy = c1.y - c2.y;
  var dist = c1.radius + c2.radius;

  return (dx * dx + dy * dy <= dist * dist)
}

Envisioning it graphically shows how the inequality relates to the Pythagorean Theorem.

Author: Daniel X

Heretic priest of the Machine God. I enjoy crawling around in Jeff Bezo's spaceship, bringing technology to the people, and long walks outside of time and space. View all posts by Daniel X