Add helper to validate (and fix) material indices of meshes' polygons, curves' splines and texts' letters.

Useful especially for importer addons.

Reviewers: campbellbarton

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D650

1 files changed, 40 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/curve.c b/source/blender/blenkernel/intern/curve.c
index 0abe956b599..eaeffdf6fef 100644
--- a/source/blender/blenkernel/intern/curve.c
+++ b/source/blender/blenkernel/intern/curve.c
@@ -52,6 +52,7 @@
 
 #include "BKE_animsys.h"
 #include "BKE_curve.h"
+#include "BKE_depsgraph.h"
 #include "BKE_displist.h"
 #include "BKE_font.h"
 #include "BKE_global.h"
@@ -4230,6 +4231,45 @@ void BKE_curve_material_index_clear(Curve *cu)
 	}
 }
 
+int BKE_curve_material_index_validate(Curve *cu)
+{
+	const int curvetype = BKE_curve_type_get(cu);
+	bool is_valid = true;
+
+	if (curvetype == OB_FONT) {
+		CharInfo *info = cu->strinfo;
+		const int max_idx = max_ii(0, cu->totcol);  /* OB_FONT use 1 as first mat index, not 0!!! */
+		int i;
+		for (i = cu->len_wchar - 1; i >= 0; i--, info++) {
+			if (info->mat_nr > max_idx) {
+				info->mat_nr = 0;
+				is_valid = false;
+			}
+		}
+	}
+	else {
+		Nurb *nu;
+		const int max_idx = max_ii(0, cu->totcol - 1);
+		for (nu = cu->nurb.first; nu; nu = nu->next) {
+			if (nu->mat_nr > max_idx) {
+				nu->mat_nr = 0;
+				if (curvetype == OB_CURVE) {
+					nu->charidx = 0;
+				}
+				is_valid = false;
+			}
+		}
+	}
+
+	if (!is_valid) {
+		DAG_id_tag_update(&cu->id, OB_RECALC_DATA);
+		return true;
+	}
+	else {
+		return false;
+	}
+}
+
 void BKE_curve_rect_from_textbox(const struct Curve *cu, const struct TextBox *tb, struct rctf *r_rect)
 {
 	r_rect->xmin = cu->xof + tb->x;