Fix T94078: Wrong Bound Box calculated for curves

`DEG_OBJECT_ITER_FOR_RENDER_ENGINE_BEGIN` creates temporary objects that
correspond to duplicates or instances.

These temporary objects can share same pointers with the original object
as in the case of Bounding Box.

Bound Box of temporary objects is marked dirty in
`BKE_object_replace_data_on_shallow_copy` since `ob->data` is different.

This causes the original Bounding Box, calculated for the evaluated
geometry, to be lost.

The solution in this commit is to change the boundbox reference of the
temporary objects, so the boundbox of the non-temporary object (with
the data curve) is not marked dirty.

Differential Revision: https://developer.blender.org/D13581

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/draw/intern/draw_manager.c b/source/blender/draw/intern/draw_manager.c
index 94950a1ff94..86ed08c5b0f 100644
--- a/source/blender/draw/intern/draw_manager.c
+++ b/source/blender/draw/intern/draw_manager.c
@@ -757,8 +757,11 @@ static void duplidata_key_free(void *key)
   }
   else {
     Object temp_object = *dupli_key->ob;
+    /* Do not modify the original boundbox. */
+    temp_object.runtime.bb = NULL;
     BKE_object_replace_data_on_shallow_copy(&temp_object, dupli_key->ob_data);
     drw_batch_cache_generate_requested(&temp_object);
+    MEM_SAFE_FREE(temp_object.runtime.bb);
   }
   MEM_freeN(key);
 }