Fix T99733: Objects with driven visibility are evaluated when not needed

The issue was caused by the fact that objects with driven or animated
visibility were considered visible by the dependency graph evaluation.

This change makes it so the dependency graph evaluation is aware of
visibility which might be changing. This is achieved by evaluating the
path of the graph which affects objects visibility and adjusts to it
before evaluating the rest of the graph.

There is some time penalty to this, but there does not seem to be a
way to fully avoid this penalty.

With the production shot from the heist project the FPS drops by a
tenth of a frame (~9.4 vs ~9.3 fps) when adding a driver to an object
which keeps it visible. Note that this is a bit hard to measure since
the FPS fluctuates quite a bit throughout the playback. On the other
hand, having a driver on a visibility of a heavy object from character
and setting visibility to false gives big speedup.

Also worth noting that there is no penalty at all when there are no
animated visibilities in the scene.

Differential Revision: https://developer.blender.org/D15498

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/depsgraph/intern/depsgraph.cc b/source/blender/depsgraph/intern/depsgraph.cc
index d460a68747d..316d0b615c6 100644
--- a/source/blender/depsgraph/intern/depsgraph.cc
+++ b/source/blender/depsgraph/intern/depsgraph.cc
@@ -45,7 +45,9 @@ namespace blender::deg {
 
 Depsgraph::Depsgraph(Main *bmain, Scene *scene, ViewLayer *view_layer, eEvaluationMode mode)
     : time_source(nullptr),
+      has_animated_visibility(false),
       need_update_relations(true),
+      need_update_nodes_visibility(true),
       need_tag_id_on_graph_visibility_update(true),
       need_tag_id_on_graph_visibility_time_update(false),
       bmain(bmain),