[Bf-blender-cvs] [8ad37b0] master: Fix T44359: `mesh_normals_loop_custom_set()` would not behave correctly with zero-normals.

[Bastien Montagne]

Commit: 8ad37b0d224fcf3eb09dd2b7def8bdcc386af1a1
Author: Bastien Montagne
Date:   Mon Apr 13 15:41:57 2015 +0200
Branches: master
https://developer.blender.org/rB8ad37b0d224fcf3eb09dd2b7def8bdcc386af1a1

Fix T44359: `mesh_normals_loop_custom_set()` would not behave correctly with zero-normals.

Zero-normals here are used as a shortcut to say 'use auto-computed values'.
So we have to do so in pre-process steps!

===================================================================

M	source/blender/blenkernel/intern/mesh_evaluate.c

===================================================================

diff --git a/source/blender/blenkernel/intern/mesh_evaluate.c b/source/blender/blenkernel/intern/mesh_evaluate.c
index ceb9b01..bbc175f 100644
--- a/source/blender/blenkernel/intern/mesh_evaluate.c
+++ b/source/blender/blenkernel/intern/mesh_evaluate.c
@@ -1349,6 +1349,10 @@ static void mesh_normals_loop_custom_set(
 					const int nidx = lidx;
 					float *nor = custom_loopnors[nidx];
 
+					if (is_zero_v3(nor)) {
+						nor = lnors[nidx];
+					}
+
 					if (!org_nor) {
 						org_nor = nor;
 					}
@@ -1408,6 +1412,10 @@ static void mesh_normals_loop_custom_set(
 					const int nidx = use_vertices ? (int)mloops[lidx].v : lidx;
 					float *nor = custom_loopnors[nidx];
 
+					if (is_zero_v3(nor)) {
+						nor = lnors[nidx];
+					}
+
 					nbr_nors++;
 					add_v3_v3(avg_nor, nor);
 					BLI_SMALLSTACK_PUSH(clnors_data, (short *)r_clnors_data[lidx]);