Get a vertex id basically a point in the basket part of your Catapult model.

You can then get an xyz coordinate in world space. You can manually attach your rock to that vertex position. Use the "vec_for_vertex" command.

Once you have an animation of your catapult throwing the rock, have your rock track the basket vertex, update the rocks position until you reach a predefined frame in your animation where you want to throw the rock as a projecticle. At this point you can enable physics on the rock and let the physics system take over. You will have to give the rock, force variables, and how it is going to react with gravity.


Ken