magnet2 | Python XMPP MUC entertainment | Bot library

There are several issues with the code. I think the main issue is that you use apply_force_at_local_point instead of apply_force_at_world_point. Apply at local point applies the force from the local point of the body. That is, both force and position should be given in body local coordinates. So for example, if you put the force position at (0,0), it means the force will be applied at the center of the body. Note that the angle should be considered as well.

Usually its easier to think in world coordinates and use the apply_force_at_world_point instead. From your code it seems like this is how you thought about it as well, as you put the point to apply the force at the body world position.

Some other issues:

1. You overwrite the mass on the rectangle Bodies. Not a problem in itself, but you will be confused :) If you set density of the shapes attached to a body they will override whatever mass you have specified. So in your code rect_mass is actually not used. Instead mass and moment of the body is calculated by using the density you set on the shape. To see the resulting mass and moment you can just print it after they are added to space: print(body.mass, body.moment)

2. In the second apply force you multiply with -1. However, the thing you multiply with is a tuple, so the end result is a empty tuple.