Big picture: Make it possible for the snap options: Vertices, Edges and Face, to work on Grease Pencil objects
- Precisely positioning a Grease Pencil object on a Mesh in the 3DView
- More flexibility in positioning the 3D Cursor
- Will work in conjunction with 3DView's snap system (no new interface required)
- Since Grease Pencil objects can be 3D, a BVHTree system may have to be implemented to snap to faces and occlusion test.
- Another option is to work with a depth buffer.