[Bf-blender-cvs] [ecfcf1b97b7] master: Cycles: disable light tree for existing scenes, enable on new scenes

[Brecht Van Lommel]

Commit: ecfcf1b97b707faa7a3076bf4d917cd333c331d8
Author: Brecht Van Lommel
Date:   Tue Dec 13 20:10:39 2022 +0100
Branches: master
https://developer.blender.org/rBecfcf1b97b707faa7a3076bf4d917cd333c331d8

Cycles: disable light tree for existing scenes, enable on new scenes

While it helps on many scenes, it can be disruptive for existing scenes and
for benchmarks the differences in timing can be confusing. So be a bit more
conservative and only it enable it for new scenes.

===================================================================

M	intern/cycles/blender/addon/version_update.py

===================================================================

diff --git a/intern/cycles/blender/addon/version_update.py b/intern/cycles/blender/addon/version_update.py
index 8ebb17e614a..7f81ac96309 100644
--- a/intern/cycles/blender/addon/version_update.py
+++ b/intern/cycles/blender/addon/version_update.py
@@ -241,6 +241,12 @@ def do_versions(self):
                         layer.samples *= layer.samples
                     cscene["use_square_samples"] = False
 
+            # Disable light tree for existing scenes.
+            if version <= (3, 5, 3):
+                cscene = scene.cycles
+                if not cscene.is_property_set("use_light_tree"):
+                    cscene.use_light_tree = False
+
         # Lamps
         for light in bpy.data.lights:
             if light.library not in libraries: