Render: Update lightgroup membership in objects and world if lightgroup is renamed

As discussed, this only updates objects in and the world of the scene to which the view layer belongs, which also avoids the problem of not having a BMain available.

Differential Revision: https://developer.blender.org/D14740

1 files changed, 26 insertions, 1 deletions

diff --git a/source/blender/blenkernel/intern/layer.c b/source/blender/blenkernel/intern/layer.c
index ac582ff69ca..dabc76f29ca 100644
--- a/source/blender/blenkernel/intern/layer.c
+++ b/source/blender/blenkernel/intern/layer.c
@@ -39,6 +39,7 @@
 #include "DNA_view3d_types.h"
 #include "DNA_windowmanager_types.h"
 #include "DNA_workspace_types.h"
+#include "DNA_world_types.h"
 
 #include "DEG_depsgraph.h"
 #include "DEG_depsgraph_debug.h"
@@ -2588,12 +2589,36 @@ ViewLayer *BKE_view_layer_find_with_lightgroup(struct Scene *scene,
   return NULL;
 }
 
-void BKE_view_layer_rename_lightgroup(ViewLayer *view_layer,
+void BKE_view_layer_rename_lightgroup(Scene *scene,
+                                      ViewLayer *view_layer,
                                       ViewLayerLightgroup *lightgroup,
                                       const char *name)
 {
+  char old_name[64];
+  BLI_strncpy_utf8(old_name, lightgroup->name, sizeof(old_name));
   BLI_strncpy_utf8(lightgroup->name, name, sizeof(lightgroup->name));
   viewlayer_lightgroup_make_name_unique(view_layer, lightgroup);
+
+  if (scene != NULL) {
+    /* Update objects in the scene to refer to the new name instead. */
+    FOREACH_SCENE_OBJECT_BEGIN (scene, ob) {
+      if (!ID_IS_LINKED(ob) && ob->lightgroup != NULL) {
+        LightgroupMembership *lgm = ob->lightgroup;
+        if (STREQ(lgm->name, old_name)) {
+          BLI_strncpy_utf8(lgm->name, lightgroup->name, sizeof(lgm->name));
+        }
+      }
+    }
+    FOREACH_SCENE_OBJECT_END;
+
+    /* Update the scene's world to refer to the new name instead. */
+    if (scene->world != NULL && !ID_IS_LINKED(scene->world) && scene->world->lightgroup != NULL) {
+      LightgroupMembership *lgm = scene->world->lightgroup;
+      if (STREQ(lgm->name, old_name)) {
+        BLI_strncpy_utf8(lgm->name, lightgroup->name, sizeof(lgm->name));
+      }
+    }
+  }
 }
 
 void BKE_lightgroup_membership_get(struct LightgroupMembership *lgm, char *name)