Fix T91986: incorrect syncing of geometry instances

The issue was that some geometries were not synced again even when
they changed. This commit adds a map that keeps track of the geometries
that need to be updated when an object has changed.

Differential Revision: https://developer.blender.org/D13020

1 files changed, 9 insertions, 0 deletions

diff --git a/intern/cycles/blender/sync.cpp b/intern/cycles/blender/sync.cpp
index cf0b77a9b16..ffd1e78b7f8 100644
--- a/intern/cycles/blender/sync.cpp
+++ b/intern/cycles/blender/sync.cpp
@@ -183,6 +183,15 @@ void BlenderSync::sync_recalc(BL::Depsgraph &b_depsgraph, BL::SpaceView3D &b_v3d
               (object_subdivision_type(b_ob, preview, experimental) != Mesh::SUBDIVISION_NONE)) {
             BL::ID key = BKE_object_is_modified(b_ob) ? b_ob : b_ob.data();
             geometry_map.set_recalc(key);
+
+            /* Sync all contained geometry instances as well when the object changed.. */
+            map<void *, set<BL::ID>>::const_iterator instance_geometries =
+                instance_geometries_by_object.find(b_ob.ptr.data);
+            if (instance_geometries != instance_geometries_by_object.end()) {
+              for (BL::ID geometry : instance_geometries->second) {
+                geometry_map.set_recalc(geometry);
+              }
+            }
           }
 
           if (updated_geometry) {