bugfix [#20768] Project Snap Broken

2 files changed, 30 insertions, 10 deletions

diff --git a/source/blender/blenkernel/BKE_bvhutils.h b/source/blender/blenkernel/BKE_bvhutils.h
index 5a1db432589..975e64929c2 100644
--- a/source/blender/blenkernel/BKE_bvhutils.h
+++ b/source/blender/blenkernel/BKE_bvhutils.h
@@ -65,6 +65,7 @@ typedef struct BVHTreeFromMesh
 
 	/* Private data */
 	int cached;
+	void *em_evil;	/* var only for snapping */
 
 } BVHTreeFromMesh;
 
diff --git a/source/blender/blenkernel/intern/bvhutils.c b/source/blender/blenkernel/intern/bvhutils.c
index 671bcb36680..882295b931c 100644
--- a/source/blender/blenkernel/intern/bvhutils.c
+++ b/source/blender/blenkernel/intern/bvhutils.c
@@ -36,6 +36,7 @@
 
 #include "BKE_DerivedMesh.h"
 #include "BKE_utildefines.h"
+#include "BLI_editVert.h"
 
 #include "BLI_math.h"
 #include "MEM_guardedalloc.h"
@@ -577,16 +578,34 @@ BVHTree* bvhtree_from_mesh_faces(BVHTreeFromMesh *data, DerivedMesh *mesh, float
 			tree = BLI_bvhtree_new(numFaces, epsilon, tree_type, axis);
 			if(tree != NULL)
 			{
-				for(i = 0; i < numFaces; i++)
-				{
-					float co[4][3];
-					VECCOPY(co[0], vert[ face[i].v1 ].co);
-					VECCOPY(co[1], vert[ face[i].v2 ].co);
-					VECCOPY(co[2], vert[ face[i].v3 ].co);
-					if(face[i].v4)
-						VECCOPY(co[3], vert[ face[i].v4 ].co);
-			
-					BLI_bvhtree_insert(tree, i, co[0], face[i].v4 ? 4 : 3);
+				/* XXX, for snap only, em & dm are assumed to be aligned, since dm is the em's cage */
+				EditMesh *em= data->em_evil;
+				if(em) {
+					EditFace *efa= em->faces.first;
+					for(i = 0; i < numFaces; i++, efa= efa->next) {
+						if(!(efa->f & 1) && efa->h==0 && !((efa->v1->f&1)+(efa->v2->f&1)+(efa->v3->f&1)+(efa->v4?efa->v4->f&1:0))) {
+							float co[4][3];
+							VECCOPY(co[0], vert[ face[i].v1 ].co);
+							VECCOPY(co[1], vert[ face[i].v2 ].co);
+							VECCOPY(co[2], vert[ face[i].v3 ].co);
+							if(face[i].v4)
+								VECCOPY(co[3], vert[ face[i].v4 ].co);
+					
+							BLI_bvhtree_insert(tree, i, co[0], face[i].v4 ? 4 : 3);
+						}
+					}
+				}
+				else {
+					for(i = 0; i < numFaces; i++) {
+						float co[4][3];
+						VECCOPY(co[0], vert[ face[i].v1 ].co);
+						VECCOPY(co[1], vert[ face[i].v2 ].co);
+						VECCOPY(co[2], vert[ face[i].v3 ].co);
+						if(face[i].v4)
+							VECCOPY(co[3], vert[ face[i].v4 ].co);
+				
+						BLI_bvhtree_insert(tree, i, co[0], face[i].v4 ? 4 : 3);
+					}
 				}
 				BLI_bvhtree_balance(tree);