How to rotate and move wheels

[ad126]

Hi I am learning chipmunk and I am trying to get a simple circle shape ball to rotate on a surface like a wheel and move forward. How can I do this?

Thanks

[slembcke]

You can attach a motor constraint to it if you want it to be powered, or you can just set the rotational velocity of the body if you just want to get it rolling.

[ad126]

Thanks for your reply slembcke. Setting the rotational velocity seems to work, but I'm not sure what the two constrained bodies would be for a simple motor on a single wheel.

[slembcke]

The motor adds torque between two bodies. In the real world it's impossible to make a wheel twist against itself (or nothing). On a vehicle, you would attach the motor from the wheel to the chassis. If you just want to make a self powered wheel you can attach the other end of the motor to the static body that you attach your static geometry to.