Curves: add taper mode option

Currently, when a taper object is specified, the radius of the spline is
ignored. This patch adds a new option to control how the taper object
affect the effective radius of the spline. The option allow three modes
of operation:

- Override: The old method. The radius of the spline is ignored and
  overridden.
- Multiply: The radius of the spline is multiplied by the taper radius.
- Add: The radius of the spline is added to the taper radius.

Ref D10779

1 files changed, 7 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/displist.c b/source/blender/blenkernel/intern/displist.c
index 708b1971bd5..d4581991566 100644
--- a/source/blender/blenkernel/intern/displist.c
+++ b/source/blender/blenkernel/intern/displist.c
@@ -1650,6 +1650,13 @@ static void do_makeDispListCurveTypes(Depsgraph *depsgraph,
                 }
 
                 radius_factor = displist_calc_taper(depsgraph, scene, cu->taperobj, taper_factor);
+
+                if (cu->taper_radius_mode == CU_TAPER_RADIUS_MULTIPLY) {
+                  radius_factor *= bevp->radius;
+                }
+                else if (cu->taper_radius_mode == CU_TAPER_RADIUS_ADD) {
+                  radius_factor += bevp->radius;
+                }
               }
 
               if (bevp->split_tag) {