2D physics programming project

Why bringing physics simulation to a game / app ?
Just because it's the best way to have a real feeling of animation/interactions between objects and forces (gravity, explosions, etc.) in a game.

First step : Dynamics
What I've done with iSnake and its GameOver screen is to bring Dynamics problem to the iPhone. Basically, how the balls are moving/accelerating depending on the gravity (given by the accelerometer), their masses and the air friction.
To make the balls bouncing each other, I've added a collision detection algorithm with momentum conservation. (detection collision between ball was very simple : calculate the distance)

Next step : Bringing rotation after collision
The bouncing balls problem was quite simple but now, I have to compute rotation and its momentum on objects.
If you hit a rectangle object in a corner, it will not move straight but rotate. This is the next physic law about torques.
I need to experiment collision detection algorithm between simple shapes : rectangles and polygons.
Then, I'll have to calculate the rotation depending on the collision impact (torque).
Example : Contacts between rigid bodies

After that, there are some interesting stuff to add, all concern constraints : springs, rotation axis, etc.


Resources :
http://www.pfirth.co.uk/ (physics programming)
http://chrishecker.com (physics theories and programming)
http://www.myphysicslab.com/contact.html (physics theories and programming)
http://www.kloonigames.com/blog/games/crayon/ (crayon physics game : worth trying :-))


Examples of 2D rigid body collisions apps

2d Physics Demo v1.0



Crayon Physics