Depsgraph: Optimize evaluation of dependencies of disabled modifiers

Solves long-standing issue when dependencies of disabled modifiers are
evaluated.

Simple test case: no drivers or animation. Manually enabling modifier
is expected to bring FPS up, enabling modifier will bring FPS (sine
evaluation can not be avoided)

F13336690

More complex test case: modifier visibility is driven by an animated
property. In am ideal world FPS during property being zero is fast
and when property is 1 the FPS is low.

F13336691.

Differential Revision: https://developer.blender.org/D15625

source/blender/depsgraph/intern/builder/deg_builder.cc

@@ -13,6 +13,7 @@
 #include "DNA_anim_types.h"
 #include "DNA_armature_types.h"
 #include "DNA_layer_types.h"
+#include "DNA_modifier_types.h"
 #include "DNA_object_types.h"
 
 #include "BLI_stack.h"
@@ -95,6 +96,24 @@ bool DepsgraphBuilder::is_object_visibility_animated(const Object *object)
   return cache_->isPropertyAnimated(&object->id, property_id);
 }
 
+bool DepsgraphBuilder::is_modifier_visibility_animated(const Object *object,
+                                                       const ModifierData *modifier)
+{
+  AnimatedPropertyID property_id;
+  if (graph_->mode == DAG_EVAL_VIEWPORT) {
+    property_id = AnimatedPropertyID(
+        &object->id, &RNA_Modifier, (void *)modifier, "show_viewport");
+  }
+  else if (graph_->mode == DAG_EVAL_RENDER) {
+    property_id = AnimatedPropertyID(&object->id, &RNA_Modifier, (void *)modifier, "show_render");
+  }
+  else {
+    BLI_assert_msg(0, "Unknown evaluation mode.");
+    return false;
+  }
+  return cache_->isPropertyAnimated(&object->id, property_id);
+}
+
 bool DepsgraphBuilder::check_pchan_has_bbone(const Object *object, const bPoseChannel *pchan)
 {
   BLI_assert(object->type == OB_ARMATURE);

source/blender/depsgraph/intern/builder/deg_builder.h

@@ -10,6 +10,7 @@
 struct Base;
 struct ID;
 struct Main;
+struct ModifierData;
 struct Object;
 struct bPoseChannel;
 
@@ -25,6 +26,7 @@ class DepsgraphBuilder {
   virtual bool need_pull_base_into_graph(const Base *base);
 
   virtual bool is_object_visibility_animated(const Object *object);
+  virtual bool is_modifier_visibility_animated(const Object *object, const ModifierData *modifier);
 
   virtual bool check_pchan_has_bbone(const Object *object, const bPoseChannel *pchan);
   virtual bool check_pchan_has_bbone_segments(const Object *object, const bPoseChannel *pchan);

source/blender/depsgraph/intern/builder/deg_builder_nodes.cc

@@ -879,9 +879,31 @@ void DepsgraphNodeBuilder::build_object_modifiers(Object *object)
     return;
   }
 
+  const ModifierMode modifier_mode = (graph_->mode == DAG_EVAL_VIEWPORT) ? eModifierMode_Realtime :
+                                                                           eModifierMode_Render;
+
+  IDNode *id_node = find_id_node(&object->id);
+
+  add_operation_node(&object->id,
+                     NodeType::GEOMETRY,
+                     OperationCode::VISIBILITY,
+                     [id_node](::Depsgraph *depsgraph) {
+                       deg_evaluate_object_modifiers_mode_node_visibility(depsgraph, id_node);
+                     });
+
   LISTBASE_FOREACH (ModifierData *, modifier, &object->modifiers) {
-    add_operation_node(
+    OperationNode *modifier_node = add_operation_node(
         &object->id, NodeType::GEOMETRY, OperationCode::MODIFIER, nullptr, modifier->name);
+
+    /* Mute modifier mode if the modifier is not enabled for the dependency graph mode.
+     * This handles static (non-animated) mode of the modifier. */
+    if ((modifier->mode & modifier_mode) == 0) {
+      modifier_node->flag |= DEPSOP_FLAG_MUTE;
+    }
+
+    if (is_modifier_visibility_animated(object, modifier)) {
+      graph_->has_animated_visibility = true;
+    }
   }
 
   BuilderWalkUserData data;

source/blender/depsgraph/intern/builder/deg_builder_relations.cc

@@ -877,6 +877,16 @@ void DepsgraphRelationBuilder::build_object_modifiers(Object *object)
       &object->id, NodeType::GEOMETRY, OperationCode::GEOMETRY_EVAL_INIT);
   const OperationKey eval_key(&object->id, NodeType::GEOMETRY, OperationCode::GEOMETRY_EVAL);
 
+  const ComponentKey object_visibility_key(&object->id, NodeType::VISIBILITY);
+  const OperationKey modifier_visibility_key(
+      &object->id, NodeType::GEOMETRY, OperationCode::VISIBILITY);
+  add_relation(modifier_visibility_key,
+               object_visibility_key,
+               "modifier -> object visibility",
+               RELATION_NO_VISIBILITY_CHANGE);
+
+  add_relation(modifier_visibility_key, eval_key, "modifier visibility -> geometry eval");
+
   ModifierUpdateDepsgraphContext ctx = {};
   ctx.scene = scene_;
   ctx.object = object;

source/blender/depsgraph/intern/builder/deg_builder_rna.cc

@@ -225,6 +225,10 @@ RNANodeIdentifier RNANodeQuery::construct_node_identifier(const PointerRNA *ptr,
     }
     return node_identifier;
   }
+
+  const char *prop_identifier = prop != nullptr ? RNA_property_identifier((PropertyRNA *)prop) :
+                                                  "";
+
   if (RNA_struct_is_a(ptr->type, &RNA_Constraint)) {
     const Object *object = reinterpret_cast<const Object *>(ptr->owner_id);
     const bConstraint *constraint = static_cast<const bConstraint *>(ptr->data);
@@ -264,6 +268,13 @@ RNANodeIdentifier RNANodeQuery::construct_node_identifier(const PointerRNA *ptr,
       return node_identifier;
     }
   }
+  else if (RNA_struct_is_a(ptr->type, &RNA_Modifier) &&
+           (contains(prop_identifier, "show_viewport") ||
+            contains(prop_identifier, "show_render"))) {
+    node_identifier.type = NodeType::GEOMETRY;
+    node_identifier.operation_code = OperationCode::VISIBILITY;
+    return node_identifier;
+  }
   else if (RNA_struct_is_a(ptr->type, &RNA_Mesh) || RNA_struct_is_a(ptr->type, &RNA_Modifier) ||
            RNA_struct_is_a(ptr->type, &RNA_GpencilModifier) ||
            RNA_struct_is_a(ptr->type, &RNA_Spline) || RNA_struct_is_a(ptr->type, &RNA_TextBox) ||
@@ -290,7 +301,6 @@ RNANodeIdentifier RNANodeQuery::construct_node_identifier(const PointerRNA *ptr,
   else if (ptr->type == &RNA_Object) {
     /* Transforms props? */
     if (prop != nullptr) {
-      const char *prop_identifier = RNA_property_identifier((PropertyRNA *)prop);
       /* TODO(sergey): How to optimize this? */
       if (contains(prop_identifier, "location") || contains(prop_identifier, "matrix_basis") ||
           contains(prop_identifier, "matrix_channel") ||

source/blender/depsgraph/intern/depsgraph_relation.h

@@ -28,6 +28,8 @@ enum RelationFlag {
   RELATION_FLAG_GODMODE = (1 << 4),
   /* Relation will check existence before being added. */
   RELATION_CHECK_BEFORE_ADD = (1 << 5),
+  /* The relation does not participate in visibility checks. */
+  RELATION_NO_VISIBILITY_CHANGE = (1 << 6),
 };
 
 /* B depends on A (A -> B) */

source/blender/depsgraph/intern/eval/deg_eval.cc

@@ -437,7 +437,7 @@ void deg_evaluate_on_refresh(Depsgraph *graph)
 
   evaluate_graph_threaded_stage(&state, task_pool, EvaluationStage::COPY_ON_WRITE);
 
-  if (graph->has_animated_visibility) {
+  if (graph->has_animated_visibility || graph->need_update_nodes_visibility) {
     /* Update pending parents including only the ones which are affecting operations which are
      * affecting visibility. */
     state.need_update_pending_parents = true;

source/blender/depsgraph/intern/eval/deg_eval_visibility.cc

@@ -8,6 +8,7 @@
 #include "intern/eval/deg_eval_visibility.h"
 
 #include "DNA_layer_types.h"
+#include "DNA_modifier_types.h"
 #include "DNA_object_types.h"
 
 #include "BLI_assert.h"
@@ -47,6 +48,38 @@ void deg_evaluate_object_node_visibility(::Depsgraph *depsgraph, IDNode *id_node
   }
 }
 
+void deg_evaluate_object_modifiers_mode_node_visibility(::Depsgraph *depsgraph, IDNode *id_node)
+{
+  BLI_assert(GS(id_node->id_cow->name) == ID_OB);
+
+  Depsgraph *graph = reinterpret_cast<Depsgraph *>(depsgraph);
+  const Object *object = reinterpret_cast<const Object *>(id_node->id_cow);
+
+  DEG_debug_print_eval(depsgraph, __func__, object->id.name, &object->id);
+
+  if (BLI_listbase_is_empty(&object->modifiers)) {
+    return;
+  }
+
+  const ModifierMode modifier_mode = (graph->mode == DAG_EVAL_VIEWPORT) ? eModifierMode_Realtime :
+                                                                          eModifierMode_Render;
+
+  const ComponentNode *geometry_component = id_node->find_component(NodeType::GEOMETRY);
+  LISTBASE_FOREACH (ModifierData *, modifier, &object->modifiers) {
+    OperationNode *modifier_node = geometry_component->find_operation(OperationCode::MODIFIER,
+                                                                      modifier->name);
+
+    const bool modifier_enabled = modifier->mode & modifier_mode;
+    const int mute_flag = modifier_enabled ? 0 : DEPSOP_FLAG_MUTE;
+    if ((modifier_node->flag & DEPSOP_FLAG_MUTE) != mute_flag) {
+      modifier_node->flag &= ~DEPSOP_FLAG_MUTE;
+      modifier_node->flag |= mute_flag;
+
+      graph->need_update_nodes_visibility = true;
+    }
+  }
+}
+
 void deg_graph_flush_visibility_flags(Depsgraph *graph)
 {
   enum {
@@ -116,11 +149,31 @@ void deg_graph_flush_visibility_flags(Depsgraph *graph)
         OperationNode *op_from = reinterpret_cast<OperationNode *>(rel->from);
         ComponentNode *comp_from = op_from->owner;
 
-        const bool target_possibly_affects_visible_id = comp_to->possibly_affects_visible_id;
-        const bool target_affects_visible_id = comp_to->affects_visible_id;
-
         op_from->flag |= (op_to->flag & OperationFlag::DEPSOP_FLAG_AFFECTS_VISIBILITY);
 
+        if (rel->flag & RELATION_NO_VISIBILITY_CHANGE) {
+          continue;
+        }
+
+        const bool target_possibly_affects_visible_id = comp_to->possibly_affects_visible_id;
+
+        bool target_affects_visible_id = comp_to->affects_visible_id;
+
+        /* This is a bit arbitrary but the idea here is following:
+         *
+         *  - When another object is used by a disabled modifier we do not want that object to
+         *    be considered needed for evaluation.
+         *
+         *  - However, we do not want to take mute flag during visibility propagation within the
+         *    same object. Otherwise drivers and transform dependencies of the geometry component
+         *    entry component might not be properly handled.
+         *
+         * This code works fine for muting modifiers, but might need tweaks when mute is used for
+         * something else. */
+        if (comp_from != comp_to && (op_to->flag & DEPSOP_FLAG_MUTE)) {
+          target_affects_visible_id = false;
+        }
+
         /* Visibility component forces all components of the current ID to be considered as
          * affecting directly visible. */
         if (comp_from->type == NodeType::VISIBILITY) {

source/blender/depsgraph/intern/eval/deg_eval_visibility.h

@@ -18,6 +18,9 @@ struct IDNode;
  * restriction flags. */
 void deg_evaluate_object_node_visibility(::Depsgraph *depsgraph, IDNode *id_node);
 
+/* Update node visibility flags based on actual modifiers mode flags. */
+void deg_evaluate_object_modifiers_mode_node_visibility(::Depsgraph *depsgraph, IDNode *id_node);
+
 /* Flush both static and dynamic visibility flags from leaves up to the roots, making it possible
  * to know whether a node has affect on something (potentially) visible. */
 void deg_graph_flush_visibility_flags(Depsgraph *graph);

source/blender/depsgraph/intern/node/deg_node_operation.cc

@@ -227,6 +227,16 @@ void OperationNode::tag_update(Depsgraph *graph, eUpdateSource source)
    * the evaluated clues that evaluation needs to happen again. */
   graph->add_entry_tag(this);
 
+  /* Enforce dynamic visibility codepath update.
+   * This ensures visibility flags are consistently propagated throughout the dependency graph when
+   * there is no animated visibility in the graph.
+   *
+   * For example this ensures that graph is updated properly when manually toggling non-animated
+   * modifier visibility. */
+  if (opcode == OperationCode::VISIBILITY) {
+    graph->need_update_nodes_visibility = true;
+  }
+
   /* Tag for update, but also note that this was the source of an update. */
   flag |= (DEPSOP_FLAG_NEEDS_UPDATE | DEPSOP_FLAG_DIRECTLY_MODIFIED);
   switch (source) {

source/blender/depsgraph/intern/node/deg_node_operation.h

@@ -219,6 +219,9 @@ enum OperationFlag {
   /* The operation directly or indirectly affects ID node visibility. */
   DEPSOP_FLAG_AFFECTS_VISIBILITY = (1 << 4),
 
+  /* Evaluation of the node is temporarily disabled. */
+  DEPSOP_FLAG_MUTE = (1 << 5),
+
   /* Set of flags which gets flushed along the relations. */
   DEPSOP_FLAG_FLUSH = (DEPSOP_FLAG_USER_MODIFIED),
 };