- Use smooth normals to displace in Above Surface mode. - Add an option to align an axis to the normal in the constraint. I've seen people request the alignment feature, and it seems useful. For the actual aligning I use the damped track logic. In order to conveniently keep mesh data needed for normal computation together, a new data structure is introduced. Reviewers: mont29 Differential Revision: https://developer.blender.org/D3762