Fix #27176: Creating a new UV layer in edit mode fails to copy previous one

Implemented copying data from active MTFACE layer to newly created.
Also, fixed the same bug with vertex colors layer.

1 files changed, 19 insertions, 0 deletions

diff --git a/source/blender/editors/mesh/mesh_data.c b/source/blender/editors/mesh/mesh_data.c
index b6940e8f8f9..f3e26cfee36 100644
--- a/source/blender/editors/mesh/mesh_data.c
+++ b/source/blender/editors/mesh/mesh_data.c
@@ -163,6 +163,17 @@ static void delete_customdata_layer(bContext *C, Object *ob, CustomDataLayer *la
 	}
 }
 
+static void copy_editface_active_customdata(EditMesh *em, int type, int index)
+{
+	EditFace *efa;
+	int n= CustomData_get_active_layer(&em->fdata, type);
+
+	for(efa= em->faces.first; efa; efa= efa->next) {
+		void *data= CustomData_em_get_n(&em->fdata, efa->data, type, n);
+		CustomData_em_set_n(&em->fdata, efa->data, type, index, data);
+	}
+}
+
 int ED_mesh_uv_texture_add(bContext *C, Mesh *me, const char *name, int active_set)
 {
 	EditMesh *em;
@@ -176,6 +187,10 @@ int ED_mesh_uv_texture_add(bContext *C, Mesh *me, const char *name, int active_s
 			return 0;
 
 		EM_add_data_layer(em, &em->fdata, CD_MTFACE, name);
+
+		if(layernum) /* copy data from active UV */
+			copy_editface_active_customdata(em, CD_MTFACE, layernum);
+
 		if(active_set || layernum==0)
 			CustomData_set_layer_active(&em->fdata, CD_MTFACE, layernum);
 	}
@@ -234,6 +249,10 @@ int ED_mesh_color_add(bContext *C, Scene *scene, Object *ob, Mesh *me, const cha
 			return 0;
 
 		EM_add_data_layer(em, &em->fdata, CD_MCOL, name);
+
+		if(layernum) /* copy data from active vertex color layer */
+			copy_editface_active_customdata(em, CD_MCOL, layernum);
+
 		if(active_set || layernum==0)
 			CustomData_set_layer_active(&em->fdata, CD_MCOL, layernum);
 	}