Use material remapping for bmesh-boolean

1 files changed, 26 insertions, 11 deletions

diff --git a/source/blender/modifiers/intern/MOD_boolean.c b/source/blender/modifiers/intern/MOD_boolean.c
index 57318e44eec..92570263856 100644
--- a/source/blender/modifiers/intern/MOD_boolean.c
+++ b/source/blender/modifiers/intern/MOD_boolean.c
@@ -54,7 +54,9 @@
 #include "MOD_util.h"
 
 #ifdef USE_BMESH
+#include "BLI_alloca.h"
 #include "BLI_math_geom.h"
+#include "BKE_material.h"
 #include "MEM_guardedalloc.h"
 
 #include "bmesh.h"
@@ -238,17 +240,30 @@ static DerivedMesh *applyModifier_bmesh(
 
 					/* we need face normals because of 'BM_face_split_edgenet'
 					 * we could calculate on the fly too (before calling split). */
-					float nmat[4][4];
-					invert_m4_m4(nmat, omat);
-
-					BMFace *efa;
-					i = 0;
-					BM_ITER_MESH (efa, &iter, bm, BM_FACES_OF_MESH) {
-						mul_transposed_mat3_m4_v3(nmat, efa->no);
-						normalize_v3(efa->no);
-						BM_elem_flag_enable(efa, BM_FACE_TAG);  /* temp tag to test which side split faces are from */
-						if (++i == i_faces_end) {
-							break;
+					{
+						float nmat[4][4];
+						invert_m4_m4(nmat, omat);
+
+						const short ob_src_totcol = bmd->object->totcol;
+						short *material_remap = BLI_array_alloca(material_remap, ob_src_totcol ? ob_src_totcol : 1);
+
+						BKE_material_remap_object_calc(ob, bmd->object, material_remap);
+
+						BMFace *efa;
+						i = 0;
+						BM_ITER_MESH (efa, &iter, bm, BM_FACES_OF_MESH) {
+							mul_transposed_mat3_m4_v3(nmat, efa->no);
+							normalize_v3(efa->no);
+							BM_elem_flag_enable(efa, BM_FACE_TAG);  /* temp tag to test which side split faces are from */
+
+							/* remap material */
+							if (LIKELY(efa->mat_nr < ob_src_totcol)) {
+								efa->mat_nr = material_remap[efa->mat_nr];
+							}
+
+							if (++i == i_faces_end) {
+								break;
+							}
 						}
 					}
 				}