[ODE] CCD Library (Re: High speed rigid body collisions)

[erwin at erwincoumans.com]

The latest Havok is continuous see their website: 

http://www.havok.com/products/physics.php 

Continuous physics requires time of impact estimation from the collision 
detector, and a physics mainloop that uses a time of impact queue. A good 
reference is Brian Mirtichs PhD. Also his paper about Time Warp contains 
good information about this topic. As long as your physics loop uses 
conservative advancement to integrate the objects you stay on the safe side. 
A raycast, a convex cast (see Gino van den Bergens paper using GJK to 
perform a linear convex cast) or other ways like Stephane Redon's papers all 
calculate the time of impact. ODE uses penetration depth to recover from 
missed collisions. However it is possible to modify ODE to allow for time of 
impact, and you can even have a hybrid system that both handles penetration 
depth and time of impact. 

I wrote a continuous collision detection library based on Stephane Redon's 
algebraic method. Also this CCD Library has convex continuous collision 
detection for both linear and angular motion, using its own GJK 
implementation. One of the examples uses the ODE quickstep solver. It is not 
ready for public release, but if someone is interested in this CCD Library 
you can contact me. 

Erwin Coumans
ccdlib at erwincoumans.com