GPencil: Fix unreported error baking mesh animation

When the mesh is linked, the materials can not be available or be the same assigned to mesh. Now, if the mesh is linked, a simple two materials conversion is used.

To get the full list of materials, the mesh must not be linked.

Also checked some indexes to be sure never get a wrong value and that materials are not created again and again.

2 files changed, 10 insertions, 4 deletions

diff --git a/source/blender/editors/gpencil/gpencil_mesh.c b/source/blender/editors/gpencil/gpencil_mesh.c
index 68ab5100bf4..11f42f7d3ac 100644
--- a/source/blender/editors/gpencil/gpencil_mesh.c
+++ b/source/blender/editors/gpencil/gpencil_mesh.c
@@ -104,9 +104,10 @@ static void gpencil_bake_duplilist(Depsgraph *depsgraph, Scene *scene, Object *o
   free_object_duplilist(lb);
 }
 
-static void gpencil_bake_ob_list(bContext *C, Depsgraph *depsgraph, Scene *scene, ListBase *list)
+static bool gpencil_bake_ob_list(bContext *C, Depsgraph *depsgraph, Scene *scene, ListBase *list)
 {
   GpBakeOb *elem = NULL;
+  bool simple_material = false;
 
   /* Add active object. In some files this could not be in selected array. */
   Object *obact = CTX_data_active_object(C);
@@ -119,6 +120,7 @@ static void gpencil_bake_ob_list(bContext *C, Depsgraph *depsgraph, Scene *scene
   /* Add duplilist. */
   else if (obact->type == OB_EMPTY) {
     gpencil_bake_duplilist(depsgraph, scene, obact, list);
+    simple_material |= true;
   }
 
   /* Add other selected objects. */
@@ -139,6 +141,8 @@ static void gpencil_bake_ob_list(bContext *C, Depsgraph *depsgraph, Scene *scene
     }
   }
   CTX_DATA_END;
+
+  return simple_material;
 }
 
 static void gpencil_bake_free_ob_list(ListBase *list)
@@ -158,7 +162,7 @@ static int gpencil_bake_mesh_animation_exec(bContext *C, wmOperator *op)
   Object *ob_gpencil = NULL;
 
   ListBase list = {NULL, NULL};
-  gpencil_bake_ob_list(C, depsgraph, scene, &list);
+  const bool simple_material = gpencil_bake_ob_list(C, depsgraph, scene, &list);
 
   /* Cannot check this in poll because the active object changes. */
   if (list.first == NULL) {
@@ -260,7 +264,8 @@ static int gpencil_bake_mesh_animation_exec(bContext *C, wmOperator *op)
                                ob_eval->obmat,
                                frame_offset,
                                use_seams,
-                               use_faces);
+                               use_faces,
+                               simple_material);
 
       /* Reproject all untaged created strokes. */
       if (project_type != GP_REPROJECT_KEEP) {
diff --git a/source/blender/editors/object/object_add.c b/source/blender/editors/object/object_add.c
index 48b50be411e..ff49e0a9c5a 100644
--- a/source/blender/editors/object/object_add.c
+++ b/source/blender/editors/object/object_add.c
@@ -2451,7 +2451,8 @@ static int object_convert_exec(bContext *C, wmOperator *op)
                                matrix,
                                0,
                                use_seams,
-                               use_faces);
+                               use_faces,
+                               false);
       gpencilConverted = true;
 
       /* Remove unused materials. */