Multipart 3D models
To allow better animation of objects, 3D models
should support a separate state for each submodel.
The state could be purely for visual purposes. Each
submodel could be rotated/scaled separately.
An MD3 model can specify multiple parts in one file
The "must have" animations:
- Doom guy run and shoot (sidestep, too?)
- Heretic's Gargoyle wings
- Monster heads turn to look at target