[PyODE] Rotation of the box always corresponds motion direct

General Discussion
1

Hello. Im using PyODE to do 2D physics in my game. I’m just learning to use ODE at the moment, so I’ve got one problem I can’t solve. How to make the rotation of the box body to be always corresponding to the direction of it? For example take a look at this picture:
jasonuniverse.appspot.com/file/a … GlrGImkAQw
When blaster shot reach the lightsaber, it’s obvious that it’s rotation around it’s axis will be corresponding to the direction (after reflection/bounce). Where should I make changes? Apply any methods to ode.Body or ode.GeomBox? Or some changes in collision handling?

		contacts = ode.collide(self.odeGeom1, self.odeGeom2)
		for contact in contacts:
			contact.setBounce(4.0)
			contact.setMu(0)
			contact.setMu2(0)
			j = ode.ContactJoint(self.odeWorld, self.odeContactGroup,contact=contact)
			j.attach(self.odeGeom1.getBody(), self.odeGeom2.getBody())

Is there a simple way to do that with ode?
That’s how the game looks for now:
jasonuniversetest.appspot.com/fi … xpaxjBtQMM
You can move lightsaber and rotate it to reflect troopers blasters and it’s working without ode, but the physics are very poor, so I wanted to use ODE to allow players to reflect blasters as they like :slight_smile: I know it’s not using panda (it uses PyGame+OpenGL+ODE), but ODE is related to Panda and there are ODE users on this forum. Thanks for help in advance :wink:

2

Since sci-fi laserbeams don’t have a mass or friction and fly at constant speeds, I not sure what you actually need physics for.

I’d calculate everything in Python. It sounds as simple as
-get the vectors of lasershot and of the saber
-get the tangent vector on collision (easily done with panda’s collision detection)
-calculate the reflected vector (there are special methods on vectors, matrices and planes for that).