Modifiers: Vertex Weight Edit add invert curve falloff option

This commit adds the option to invert the resulting weights of the
falloff curve.

There is a workflow used by some to convert a texture mask into
vertex weights by using a custom curve and inverting the points.
This allows the same effect with a single click, and gives the modifier
more procedural functionality.

With minor UI tweaks by @mont29.

Differential Revision: https://developer.blender.org/D6899

1 files changed, 8 insertions, 0 deletions

diff --git a/source/blender/modifiers/intern/MOD_weightvgedit.c b/source/blender/modifiers/intern/MOD_weightvgedit.c
index 6acbbefe745..2b2a4cf85ea 100644
--- a/source/blender/modifiers/intern/MOD_weightvgedit.c
+++ b/source/blender/modifiers/intern/MOD_weightvgedit.c
@@ -244,6 +244,14 @@ static Mesh *applyModifier(ModifierData *md, const ModifierEvalContext *ctx, Mes
     }
   }
 
+  /* Invert resulting weights */
+  if ((wmd->edit_flags & MOD_WVG_INVERT_FALLOFF) != 0) {
+    for (i = 0; i < numVerts; i++) {
+      new_w[i] = 1.0f - new_w[i];
+    }
+  }
+
+
   /* Do masking. */
   struct Scene *scene = DEG_get_evaluated_scene(ctx->depsgraph);
   weightvg_do_mask(ctx,