Trouble understanding physics (JME3)


i have some trouble understanding physics on JME3.

I do have a model which consists of 3 parts, so i create a Node() and attach the 3 spatials onto it.

Then i create DynamicMeshShape (yes, i know its slow, i might change it to something else later) on the spatial parts.

If i then enable the debug output of the collision shape and move and/or rotate the Node where the 3 spatials are attached, but the collision shape stays where it is.

I am moving the Node, because it acts as a parent of the objects, whereas the collider shapes have no parent.

How can i solve this?

The collision shape of physics objects is static, the children of compound collision shapes cannot be repositioned but just added and removed. So if you want to change the collision shape you either have to recreate the collision shape from the geometry or replace the single parts. Another approach would be making single physics objects instead of one object and then connecting the single objects with joints to move them relatively to each other. This way you can move them separately but still have them connected.

Hope this helps,