The depsgraph was always created within a fixed evaluation context. Passing
both risks the depsgraph and evaluation context not matching, and it
complicates the Python API where we'd have to expose both which is not so
easy to understand.
This also removes the global evaluation context in main, which assumed there
to be a single active scene and view layer.
Differential Revision: https://developer.blender.org/D3152
Note that some little parts of code have been dissabled because eval_ctx
was not available there. This should be resolved once DerivedMesh is
replaced.
After some discussion it seems both are valid defaults but useful for
very different purposes.
- 'free' lets you explore the scene with full 6dof (like fly mode)
- 'orbit' is closer to typical mouse view orbit, constraining to orbiting about a central location.
This doesn't effect orbit/pan which are available with modifier keys.
