Fix: The radial control would fail, in sculpt mode, to set size if object-space sizing was enabled.

This was caused because a small part of sculpt's radial control code did not make it into the new version.  The old code would set a new object-space size by scaling it proportional to how much the new screen-space size was changed.  

The solution I implement here is to do the same scaling inside the RNA callbacks.  This way, users of those properties do not have to worry about inconsistency.

I added a comment warning that brush_set_size, brush_set_unified_size, brush_unprojected_radius, and brush_set_unprojected_radius do not guarantee consistency because it is not always possible to precisely know what the new unprojected radius is in all contexts where you might set the size.  

I would implement the consistency check at the lower level (in those listed functions) but at this time I think it needs to be looked at to make sure that won't cause problems.  In addition, I am not sure that scaling by the ratio of change is strictly correct in all cases.

In any case, this at least fixes the immediate problem.

1 files changed, 13 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/brush.c b/source/blender/blenkernel/intern/brush.c
index 98c540f53b7..25b60fef6dd 100644
--- a/source/blender/blenkernel/intern/brush.c
+++ b/source/blender/blenkernel/intern/brush.c
@@ -1251,6 +1251,19 @@ static short unified_settings(Brush *brush)
 	return 0;
 }
 
+// XXX: be careful about setting size and unprojected radius
+// because they depend on one another
+// these functions do not set the other corresponding value
+// this can lead to odd behavior if size and unprojected
+// radius become inconsistent.
+// the biggest problem is that it isn't possible to change
+// unprojected radius because a view context is not
+// available.  my ussual solution to this is to use the
+// ratio of change of the size to change the unprojected
+// radius.  Not completely convinced that is correct.
+// In anycase, a better solution is needed to prevent
+// inconsistency.
+
 static void set_unified_size(Brush *brush, int value)
 {
 	Scene *sce;