when experimenting compass. nodes and lookAt attribute, this message was prompt:
AssertionError: has_mat() && is_2d() at line 666 of c:\p\p3d\panda3d-1.6.2\panda\src\pgraph\transformState.IIt means something you did assumed that some particular transform represented a valid 2-d operation, but it turns out it didn’t.
I don’t know what specifically triggered the assertion in your case. I’d have to know more about the specific code you were running.
David