I have rearranged the code from Fauerby’s paper into a single Javascript function (class) in a separate file.  I called it CollisionSystem and a single instance of that function keeps up with everything related to collisions.  Fauerby used a “CollisionPackage” (or “CollisionPacket”, depending on where you look in the code) to pass variables to the collision functions.  I moved that into a single class with the appropriate members and methods.  So now my code looks like this:

var _cs = new CollisionSystem();

_cs.collisionTargets.push(collidableObject);

var newPosition = _cs.run(position, velocity);

position = newPosition;

Once the CollisionSystem is created and at least one collisionTarget is added to it, I just call run with the collider’s current position and velocity.  run returns the new position and I can then update the scene with that position.  Easy peasy chicken squeezy.

A current limitation of the system is that I’m not implementing gravity right now.  That will need to be done eventually, but I thought I could add that later after the core system is running.  I’m also not taking a collidableObject‘s rotation into account at the moment.  This will obviously need to be implemented but it shouldn’t be difficult at all.  I’ll need to look through the code to confirm this but I believe that the collider has a hard-coded radius of 1.  Since the base unit in Lyridia is 1 meter, a collider sphere with a diameter of 2 meters is really just too big for a humanoid player character, so that will need to be adjusted.

My next step is to take my CollisionSystem class and bring it into the rest of Lyridia’s code base.  The only real challenge with that is that the player doesn’t move based on velocity directly right now, but that should be easy to change.