Depsgraph: cache effector relations, for performance and stability.

To find all effectors in the scene, we need to loop over all objects.
Doing this during depsgraph evaluation caused crashes because not all
objects are guaranteed to be evaluated yet.

To fix this, we now cache the relations as part of the dependency graph
build. As a bonus this also makes evaluation faster for big scenes,
since looping over all objects for each particle system is slow.

Fixes T55156.

1 files changed, 17 insertions, 13 deletions

diff --git a/source/blender/blenkernel/intern/particle_system.c b/source/blender/blenkernel/intern/particle_system.c
index 1c50e85668d..d6a29531482 100644
--- a/source/blender/blenkernel/intern/particle_system.c
+++ b/source/blender/blenkernel/intern/particle_system.c
@@ -93,6 +93,7 @@
 #include "BKE_bvhutils.h"
 
 #include "DEG_depsgraph.h"
+#include "DEG_depsgraph_physics.h"
 #include "DEG_depsgraph_query.h"
 
 #include "PIL_time.h"
@@ -1307,9 +1308,10 @@ void psys_update_particle_tree(ParticleSystem *psys, float cfra)
 
 static void psys_update_effectors(ParticleSimulationData *sim)
 {
-	pdEndEffectors(&sim->psys->effectors);
-	sim->psys->effectors = pdInitEffectors(sim->depsgraph, sim->scene, sim->ob, sim->psys,
-	                                       sim->psys->part->effector_weights, true);
+	BKE_effectors_free(sim->psys->effectors);
+	sim->psys->effectors = BKE_effectors_create(sim->depsgraph,
+	                                            sim->scene, sim->ob, sim->psys,
+	                                            sim->psys->part->effector_weights);
 	precalc_guides(sim, sim->psys->effectors);
 }
 
@@ -2066,7 +2068,7 @@ static void basic_force_cb(void *efdata_v, ParticleKey *state, float *force, flo
 	/* add effectors */
 	pd_point_from_particle(efdata->sim, efdata->pa, state, &epoint);
 	if (part->type != PART_HAIR || part->effector_weights->flag & EFF_WEIGHT_DO_HAIR)
-		pdDoEffectors(sim->psys->effectors, sim->colliders, part->effector_weights, &epoint, force, impulse);
+		BKE_effectors_apply(sim->psys->effectors, sim->colliders, part->effector_weights, &epoint, force, impulse);
 
 	mul_v3_fl(force, efdata->ptex.field);
 	mul_v3_fl(impulse, efdata->ptex.field);
@@ -2957,18 +2959,20 @@ static void psys_update_path_cache(ParticleSimulationData *sim, float cfra, cons
 
 
 	/* particle instance modifier with "path" option need cached paths even if particle system doesn't */
-	FOREACH_SCENE_OBJECT_BEGIN(sim->scene, ob)
-	{
-		ModifierData *md = modifiers_findByType(ob, eModifierType_ParticleInstance);
-		if (md) {
-			ParticleInstanceModifierData *pimd = (ParticleInstanceModifierData *)md;
-			if (pimd->flag & eParticleInstanceFlag_Path && pimd->ob == sim->ob && pimd->psys == (psys - (ParticleSystem*)sim->ob->particlesystem.first)) {
-				skip = 0;
-				break;
+	if (skip) {
+		FOREACH_SCENE_OBJECT_BEGIN(sim->scene, ob)
+		{
+			ModifierData *md = modifiers_findByType(ob, eModifierType_ParticleInstance);
+			if (md) {
+				ParticleInstanceModifierData *pimd = (ParticleInstanceModifierData *)md;
+				if (pimd->flag & eParticleInstanceFlag_Path && pimd->ob == sim->ob && pimd->psys == (psys - (ParticleSystem*)sim->ob->particlesystem.first)) {
+					skip = 0;
+					break;
+				}
 			}
 		}
+		FOREACH_SCENE_OBJECT_END;
 	}
-	FOREACH_SCENE_OBJECT_END;
 
 	if (!skip) {
 		psys_cache_paths(sim, cfra, use_render_params);