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, 15 insertions, 2 deletions

diff --git a/source/blender/depsgraph/intern/node/deg_node_id.h b/source/blender/depsgraph/intern/node/deg_node_id.h
index 406ca828049..7f0a656cb8d 100644
--- a/source/blender/depsgraph/intern/node/deg_node_id.h
+++ b/source/blender/depsgraph/intern/node/deg_node_id.h
@@ -91,8 +91,21 @@ struct IDNode : public Node {
 
   eDepsNode_LinkedState_Type linked_state;
 
-  /* Indicates the data-block is visible in the evaluated scene. */
-  bool is_directly_visible;
+  /* Indicates the data-block is to be considered visible in the evaluated scene.
+   *
+   * This flag is set during dependency graph build where check for an actual visibility might not
+   * be available yet due to driven or animated restriction flags. So it is more of an intent or,
+   * in other words, plausibility of the data-block to be visible. */
+  bool is_visible_on_build;
+
+  /* Evaluated state of whether evaluation considered this data-block "enabled".
+   *
+   * For objects this is derived from the base restriction flags, which might be animated or
+   * driven. It is set to `BASE_ENABLED_<VIEWPORT, RENDER>` (depending on the graph mode) after
+   * the object's flags from layer were evaluated.
+   *
+   * For other data-types is currently always true. */
+  bool is_enabled_on_eval;
 
   /* For the collection type of ID, denotes whether collection was fully
    * recursed into. */