[Bf-blender-cvs] [90f194616b5] master: Depsgraph: clear update flags when skipping through no-op nodes.

[Alexander Gavrilov]

Commit: 90f194616b51d3c5df32cb947de83616aa3dcbde
Author: Alexander Gavrilov
Date:   Mon Dec 26 19:39:41 2022 +0200
Branches: master
https://developer.blender.org/rB90f194616b51d3c5df32cb947de83616aa3dcbde

Depsgraph: clear update flags when skipping through no-op nodes.

As an optimization, dependency graph evaluation skips through
no-op nodes at the scheduling stage. However, that leaves update
flags enabled on the node, and the most problematic one is the
USER_MODIFIED flag, which get flushed to children every time
the no-op node is tagged.

This in turn can cause simulation caches downstream to be
permanently stuck in an outdated state until the depsgraph
is rebuilt and the stuck flag cleared out.

Differential Revision: https://developer.blender.org/D16868

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

M	source/blender/depsgraph/intern/eval/deg_eval.cc
M	source/blender/depsgraph/intern/node/deg_node_operation.h

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

diff --git a/source/blender/depsgraph/intern/eval/deg_eval.cc b/source/blender/depsgraph/intern/eval/deg_eval.cc
index 5ca32d00ba5..3bdc33b8d01 100644
--- a/source/blender/depsgraph/intern/eval/deg_eval.cc
+++ b/source/blender/depsgraph/intern/eval/deg_eval.cc
@@ -105,8 +105,7 @@ void evaluate_node(const DepsgraphEvalState *state, OperationNode *operation_nod
    * times.
    * This is a thread-safe modification as the node's flags are only read for a non-scheduled nodes
    * and this node has been scheduled. */
-  operation_node->flag &= ~(DEPSOP_FLAG_DIRECTLY_MODIFIED | DEPSOP_FLAG_NEEDS_UPDATE |
-                            DEPSOP_FLAG_USER_MODIFIED);
+  operation_node->flag &= ~DEPSOP_FLAG_CLEAR_ON_EVAL;
 }
 
 void deg_task_run_func(TaskPool *pool, void *taskdata)
@@ -270,6 +269,10 @@ void schedule_node(DepsgraphEvalState *state,
   bool is_scheduled = atomic_fetch_and_or_uint8((uint8_t *)&node->scheduled, uint8_t(true));
   if (!is_scheduled) {
     if (node->is_noop()) {
+      /* Clear flags to avoid affecting subsequent update propagation.
+       * For normal nodes these are cleared when it is evaluated. */
+      node->flag &= ~DEPSOP_FLAG_CLEAR_ON_EVAL;
+
       /* skip NOOP node, schedule children right away */
       schedule_children(state, node, schedule_fn);
     }
diff --git a/source/blender/depsgraph/intern/node/deg_node_operation.h b/source/blender/depsgraph/intern/node/deg_node_operation.h
index 1bc4b36141e..df4a157d486 100644
--- a/source/blender/depsgraph/intern/node/deg_node_operation.h
+++ b/source/blender/depsgraph/intern/node/deg_node_operation.h
@@ -224,6 +224,10 @@ enum OperationFlag {
 
   /* Set of flags which gets flushed along the relations. */
   DEPSOP_FLAG_FLUSH = (DEPSOP_FLAG_USER_MODIFIED),
+
+  /* Set of flags which get cleared upon evaluation. */
+  DEPSOP_FLAG_CLEAR_ON_EVAL = (DEPSOP_FLAG_DIRECTLY_MODIFIED | DEPSOP_FLAG_NEEDS_UPDATE |
+                               DEPSOP_FLAG_USER_MODIFIED),
 };
 
 /* Atomic Operation - Base type for all operations */