Creating a Fast and Stable 2D Pixel Perfect Rigid-Body Simulation using Verlet Integration
 

Jamie Cheng

June 13, 2003

jamie.cheng@gmail.com

 

Abstract

This paper describes a simple implementation of creating a fast, stable, 2D rigid-body physics engine that can take arbitrary sprites for the collision zones. We combine Jakobsen’s work on advanced character physics [4] with pixel perfect collision detection and resolution. The system allows designers to supply mass, restitution, coefficient of static friction and kinetic friction, and supports the developer with additional information such as the point and normal of collision.

            The implementation as described in here is not meant to be extremely accurate in regards to simulation, but rather a relatively fast way to calculate realistic looking movement. For an in-depth discussion on accurate simulations, refer to classic papers such as those by Baraff [1]. The approach shown here combines old techniques of physically based modeling with new ones (with respect to the game industry) of approximating motion using Verlet Integration.

Table of Contents

Abstract 1

Table of Contents. 1

1     Introduction. 2

2     Modeling motion. 2

2.1      The Model 2

2.2      Changing Velocity