Vertex/Weight Paint: Use PBVH for painting

2016 GSOC project by @nathanvollmer, see D2150

- Mirrored painting and radial symmetry, like in sculpt mode.
- Volume based splash prevention,
  which avoids painting vertices far away from the 3D brush location.
- Normal based splash prevention,
  which avoids painting vertices with normals opposite the normal
  at the 3D brush location.
- Blur mode now uses a nearest neighbor average.
- Average mode, which averages the color/weight
  of the vertices within the brush
- Smudge mode, which pulls the colors/weights
  along the direction of the brush
- RGB^2 color blending, which gives a more accurate
  blend between two colors
- multithreading support. (PBVH leaves are painted in parallel.)
- Foreground/background color picker in vertex paint

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/pbvh_intern.h b/source/blender/blenkernel/intern/pbvh_intern.h
index 19d3b31bd31..01057318568 100644
--- a/source/blender/blenkernel/intern/pbvh_intern.h
+++ b/source/blender/blenkernel/intern/pbvh_intern.h
@@ -149,6 +149,8 @@ struct PBVH {
 	 * objects in sculpt mode with different sizes at the same time, so now storing that common gpu buffer
 	 * in an opaque pointer per pbvh. See T47637. */
 	struct GridCommonGPUBuffer *grid_common_gpu_buffer;
+	/* The ccgdm is required for CD_ORIGINDEX lookup in vertex paint + multires */
+	struct CCGDerivedMesh *ccgdm;
 
 	/* Only used during BVH build and update,
 	 * don't need to remain valid after */