Fix for crash caused by effectors doing precalculation //during// DAG

updates.

This file crashes on loading with NULL pointer access to curve_cache:
{F77132}

The pdInitEffectors function was amalgamating the simple
collection of effector objects with an automatic precalculation for
curve guides and the like. This precalculation requires object data
that may not be available until the DAG has finished.

Since for DAG dependencies only the list of effectors is required,
added an argument to disable precalculation when collecting effectors.

1 files changed, 55 insertions, 43 deletions

diff --git a/source/blender/blenkernel/intern/effect.c b/source/blender/blenkernel/intern/effect.c
index a8124c0f9c0..fc18a204526 100644
--- a/source/blender/blenkernel/intern/effect.c
+++ b/source/blender/blenkernel/intern/effect.c
@@ -166,45 +166,6 @@ void free_partdeflect(PartDeflect *pd)
 	MEM_freeN(pd);
 }
 
-static void precalculate_effector(EffectorCache *eff)
-{
-	unsigned int cfra = (unsigned int)(eff->scene->r.cfra >= 0 ? eff->scene->r.cfra : -eff->scene->r.cfra);
-	if (!eff->pd->rng)
-		eff->pd->rng = BLI_rng_new(eff->pd->seed + cfra);
-	else
-		BLI_rng_srandom(eff->pd->rng, eff->pd->seed + cfra);
-
-	if (eff->pd->forcefield == PFIELD_GUIDE && eff->ob->type==OB_CURVE) {
-		Curve *cu= eff->ob->data;
-		if (cu->flag & CU_PATH) {
-			if (eff->ob->curve_cache == NULL || eff->ob->curve_cache->path==NULL || eff->ob->curve_cache->path->data==NULL)
-				BKE_displist_make_curveTypes(eff->scene, eff->ob, 0);
-
-			if (eff->ob->curve_cache->path && eff->ob->curve_cache->path->data) {
-				where_on_path(eff->ob, 0.0, eff->guide_loc, eff->guide_dir, NULL, &eff->guide_radius, NULL);
-				mul_m4_v3(eff->ob->obmat, eff->guide_loc);
-				mul_mat3_m4_v3(eff->ob->obmat, eff->guide_dir);
-			}
-		}
-	}
-	else if (eff->pd->shape == PFIELD_SHAPE_SURFACE) {
-		eff->surmd = (SurfaceModifierData *)modifiers_findByType( eff->ob, eModifierType_Surface );
-		if (eff->ob->type == OB_CURVE)
-			eff->flag |= PE_USE_NORMAL_DATA;
-	}
-	else if (eff->psys)
-		psys_update_particle_tree(eff->psys, eff->scene->r.cfra);
-
-	/* Store object velocity */
-	if (eff->ob) {
-		float old_vel[3];
-
-		BKE_object_where_is_calc_time(eff->scene, eff->ob, cfra - 1.0f);
-		copy_v3_v3(old_vel, eff->ob->obmat[3]);
-		BKE_object_where_is_calc_time(eff->scene, eff->ob, cfra);
-		sub_v3_v3v3(eff->velocity, eff->ob->obmat[3], old_vel);
-	}
-}
 static EffectorCache *new_effector_cache(Scene *scene, Object *ob, ParticleSystem *psys, PartDeflect *pd)
 {
 	EffectorCache *eff = MEM_callocN(sizeof(EffectorCache), "EffectorCache");
@@ -213,9 +174,6 @@ static EffectorCache *new_effector_cache(Scene *scene, Object *ob, ParticleSyste
 	eff->psys = psys;
 	eff->pd = pd;
 	eff->frame = -1;
-
-	precalculate_effector(eff);
-
 	return eff;
 }
 static void add_object_to_effectors(ListBase **effectors, Scene *scene, EffectorWeights *weights, Object *ob, Object *ob_src)
@@ -264,7 +222,8 @@ static void add_particles_to_effectors(ListBase **effectors, Scene *scene, Effec
 }
 
 /* returns ListBase handle with objects taking part in the effecting */
-ListBase *pdInitEffectors(Scene *scene, Object *ob_src, ParticleSystem *psys_src, EffectorWeights *weights)
+ListBase *pdInitEffectors(Scene *scene, Object *ob_src, ParticleSystem *psys_src,
+                          EffectorWeights *weights, bool precalc)
 {
 	Base *base;
 	unsigned int layer= ob_src->lay;
@@ -302,6 +261,10 @@ ListBase *pdInitEffectors(Scene *scene, Object *ob_src, ParticleSystem *psys_src
 			}
 		}
 	}
+	
+	if (precalc)
+		pdPrecalculateEffectors(effectors);
+	
 	return effectors;
 }
 
@@ -321,6 +284,55 @@ void pdEndEffectors(ListBase **effectors)
 	}
 }
 
+static void precalculate_effector(EffectorCache *eff)
+{
+	unsigned int cfra = (unsigned int)(eff->scene->r.cfra >= 0 ? eff->scene->r.cfra : -eff->scene->r.cfra);
+	if (!eff->pd->rng)
+		eff->pd->rng = BLI_rng_new(eff->pd->seed + cfra);
+	else
+		BLI_rng_srandom(eff->pd->rng, eff->pd->seed + cfra);
+
+	if (eff->pd->forcefield == PFIELD_GUIDE && eff->ob->type==OB_CURVE) {
+		Curve *cu= eff->ob->data;
+		if (cu->flag & CU_PATH) {
+			if (eff->ob->curve_cache == NULL || eff->ob->curve_cache->path==NULL || eff->ob->curve_cache->path->data==NULL)
+				BKE_displist_make_curveTypes(eff->scene, eff->ob, 0);
+
+			if (eff->ob->curve_cache->path && eff->ob->curve_cache->path->data) {
+				where_on_path(eff->ob, 0.0, eff->guide_loc, eff->guide_dir, NULL, &eff->guide_radius, NULL);
+				mul_m4_v3(eff->ob->obmat, eff->guide_loc);
+				mul_mat3_m4_v3(eff->ob->obmat, eff->guide_dir);
+			}
+		}
+	}
+	else if (eff->pd->shape == PFIELD_SHAPE_SURFACE) {
+		eff->surmd = (SurfaceModifierData *)modifiers_findByType( eff->ob, eModifierType_Surface );
+		if (eff->ob->type == OB_CURVE)
+			eff->flag |= PE_USE_NORMAL_DATA;
+	}
+	else if (eff->psys)
+		psys_update_particle_tree(eff->psys, eff->scene->r.cfra);
+
+	/* Store object velocity */
+	if (eff->ob) {
+		float old_vel[3];
+
+		BKE_object_where_is_calc_time(eff->scene, eff->ob, cfra - 1.0f);
+		copy_v3_v3(old_vel, eff->ob->obmat[3]);
+		BKE_object_where_is_calc_time(eff->scene, eff->ob, cfra);
+		sub_v3_v3v3(eff->velocity, eff->ob->obmat[3], old_vel);
+	}
+}
+
+void pdPrecalculateEffectors(ListBase *effectors)
+{
+	if (effectors) {
+		EffectorCache *eff = effectors->first;
+		for (; eff; eff=eff->next)
+			precalculate_effector(eff);
+	}
+}
+
 
 void pd_point_from_particle(ParticleSimulationData *sim, ParticleData *pa, ParticleKey *state, EffectedPoint *point)
 {