- the name of the enumerator `SNAP_NOT_OBEDIT` was changed to `SNAP_NOT_ACTIVE`.
- the parameter `snap_to_flag` was moved to outside `SnapObjectParams`.
- the member `use_object_edit` was renamed to `use_object_edit_cage`.
- added the arg `params` in `ED_transform_snap_object_project_ray`.
- simplifications in the loop of the function `snapObjectsRay`.
Take advantage of the efficiency provided by the snap_context.
Also fixes errors:
- volume snap fails based on view angle (T48394).
- multiple instances of dupli-objects break volume calculation.
Separate the creation of trees from EditMesh from the creation of trees from DerivedMesh.
This was meant to simplify the API, but didn't work out so well.
`bvhtree_from_mesh_*` actually is working as `bvhtree_from_derivedmesh_*`.
This is inconsistent with the trees created from EditMesh. Since for create them does not use the DerivedMesh.
In such cases the dm is being used only to cache the tree in the struct DerivedMesh. What is immediately released once
bvhtree is being used in functions that change(tag) the DM cleaning the cache.
- Use a filter function so users of SnapObjectContext can define how edit-mesh elements are handled.
- Remove em_evil.
- bvhtree of EditMesh is now really cached in the snap functions.
- Code becomes organized and easier to maintain.
This is an important patch for future improvements in snapping functions.
