Shrinkwrap: implement the use of smooth normals in constraint & modifier.

- 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

1 files changed, 7 insertions, 0 deletions

diff --git a/release/scripts/startup/bl_ui/properties_constraint.py b/release/scripts/startup/bl_ui/properties_constraint.py
index ea3b5f000ec..4be1f55b3b8 100644
--- a/release/scripts/startup/bl_ui/properties_constraint.py
+++ b/release/scripts/startup/bl_ui/properties_constraint.py
@@ -769,6 +769,13 @@ class ConstraintButtonsPanel:
             rowsub.prop(con, "use_invert_cull")
             layout.prop(con, "project_limit")
 
+        if con.shrinkwrap_type in ['PROJECT', 'NEAREST_SURFACE']:
+            layout.prop(con, "use_track_normal")
+
+            row = layout.row(align=True)
+            row.active = con.use_track_normal
+            row.prop(con, "track_axis", expand=True)
+
     def DAMPED_TRACK(self, context, layout, con):
         self.target_template(layout, con)