== Multires ==

Fixed bug #5815, Multires mesh UVs get lost (or crashes!) when adding additional UV layers

* Switching to Face Select mode adds a UV layer automatically, was missing code there to add the layer to multires as well
* Adding/Deleting a customdata layer on a multires mesh should update the multires data first

source/blender/src/editface.c

@@ -90,6 +90,7 @@
 #include "mydevice.h"
 #include "blendef.h"
 #include "butspace.h"
+#include "multires.h"
 
 #include "BSE_trans_types.h"
 
@@ -610,9 +611,16 @@ void default_uv(float uv[][2], float size)
 
 void make_tfaces(Mesh *me) 
 {
-	if(!me->mtface)
+	if(!me->mtface) {
-		me->mtface= CustomData_add_layer(&me->fdata, CD_MTFACE, CD_DEFAULT,
+		if(me->mr) {
-			NULL, me->totface);
+			multires_add_layer(me, &me->mr->fdata, CD_MTFACE,
+			                   CustomData_number_of_layers(&me->fdata, CD_MTFACE));
+		}
+		else {
+			me->mtface= CustomData_add_layer(&me->fdata, CD_MTFACE, CD_DEFAULT,
+				NULL, me->totface);
+		}
+	}
 }
 
 void reveal_tface()

source/blender/src/multires-firstlevel.c

@@ -346,6 +346,8 @@ void multires_delete_layer(Mesh *me, CustomData *cd, const int type, int n)
 	if(me && me->mr && cd) {
 		MultiresLevel *lvl1= me->mr->levels.first;
 		
+		multires_update_levels(me);
+		
 		CustomData_set_layer_active(cd, type, n);
 		CustomData_free_layer_active(cd, type, lvl1->totface);
 		
@@ -357,6 +359,8 @@ MultiresLevel *current_level(Multires *mr);
 void multires_add_layer(Mesh *me, CustomData *cd, const int type, const int n)
 {
 	if(me && me->mr && cd) {
+		multires_update_levels(me);
+	
 		if(CustomData_has_layer(cd, type))
 			CustomData_add_layer(cd, type, CD_DUPLICATE, CustomData_get_layer(cd, type),
 			                     current_level(me->mr)->totface);