Box2D Forums

Hey all,

I'm working on a sidescrolling vehicle game. I'm making my terrain out of polygons with SetAsEdge() and once my vehicle gets any amount of speed, it starts to bounce wildly. To simplify the problem, I removed everything except for 1 tire and gave it a constant torque and then I built two tracks:

The first one is made out of one really long edge and has no problems:
http://www.grozzler.com/temp/one-line.swf

The second one is made out of multiple edges and you can see the wheel begins to bounce wildly:
http://www.grozzler.com/temp/segments.swf

The friction is at 1.0 and the restitution is at 0 for the ground and the wheel. I've played with the gravity, density, iterations and time steps and nothing seems to help. Any time that wheel hits the corner of another edge, it jumps.

I'm out of ideas.

Anyone have some insights?

Check out "4.5 Edge Shapes" and "4.6 Chain Shapes" in the manual.
http://box2d.org/manual.html#_Toc258082970

You might need a more recent version of Box2D though... not sure what the latest available for flash is atm.

Thanks a lot irresistible force, I've switched over to the Alchemy port and everything seems to be working great.