From 350d490a1328536447ec11d2461e4d30546ee8a0 Mon Sep 17 00:00:00 2001 From: Bastien Montagne Date: Fri, 11 Dec 2020 18:12:29 +0100 Subject: Fix T83280: Crash when deleting hair collision collection. Root of the issue was missing management of ID pointers in the cloth modifier data stored in ParticleSystem for hair physics, in the 'foreach_id' particle system code. Using modifier's 'foreach_id' code in psys one unfortunately requires some ugly conversion gymnastics, but this is still better than having dedicated code for that case. Note that this is actually a fairly critical issue, fix should be backported to 2.91.1 should we do it, and to 2.83 LTS as well I think. --- source/blender/blenkernel/intern/particle_system.c | 30 +++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/source/blender/blenkernel/intern/particle_system.c b/source/blender/blenkernel/intern/particle_system.c index f7400264131..b3472bfe716 100644 --- a/source/blender/blenkernel/intern/particle_system.c +++ b/source/blender/blenkernel/intern/particle_system.c @@ -4190,7 +4190,7 @@ static void particles_fluid_step(ParticleSimulationData *sim, ParticleSettings *part = psys->part; ParticleData *pa = NULL; - int p, totpart, tottypepart = 0; + int p, totpart = 0, tottypepart = 0; int flagActivePart, activeParts = 0; float posX, posY, posZ, velX, velY, velZ; float resX, resY, resZ; @@ -4971,6 +4971,24 @@ void particle_system_update(struct Depsgraph *depsgraph, /* ID looper */ +/* unfortunately PSys and modifier ID loopers are not directly compatible, so we need this struct + * and the callback below to map the former to the latter (thanks to psys embedding a Cloth + * modifier data struct now, for Hair physics simulations). */ +typedef struct ParticleSystemIDLoopForModifier { + ParticleSystem *psys; + ParticleSystemIDFunc func; + void *userdata; +} ParticleSystemIDLoopForModifier; + +static void particlesystem_modifiersForeachIDLink(void *user_data, + Object *UNUSED(object), + ID **id_pointer, + int cb_flag) +{ + ParticleSystemIDLoopForModifier *data = (ParticleSystemIDLoopForModifier *)user_data; + data->func(data->psys, id_pointer, data->userdata, cb_flag); +} + void BKE_particlesystem_id_loop(ParticleSystem *psys, ParticleSystemIDFunc func, void *userdata) { ParticleTarget *pt; @@ -4979,6 +4997,16 @@ void BKE_particlesystem_id_loop(ParticleSystem *psys, ParticleSystemIDFunc func, func(psys, (ID **)&psys->target_ob, userdata, IDWALK_CB_NOP); func(psys, (ID **)&psys->parent, userdata, IDWALK_CB_NOP); + if (psys->clmd != NULL) { + const ModifierTypeInfo *mti = modifierType_getInfo(psys->clmd->modifier.type); + + if (mti->foreachIDLink != NULL) { + ParticleSystemIDLoopForModifier data = {.psys = psys, .func = func, .userdata = userdata}; + mti->foreachIDLink( + &psys->clmd->modifier, NULL, particlesystem_modifiersForeachIDLink, &data); + } + } + for (pt = psys->targets.first; pt; pt = pt->next) { func(psys, (ID **)&pt->ob, userdata, IDWALK_CB_NOP); } -- cgit v1.2.3