Particles: give emitter its own state

High quality emitters need to maintain state themselves. For example,
this it needs to remember when it spawned the last particle.
This is especially important when the birth rate is changing over time.
Otherwise, there will be very visible artifacts.

It is quite likely that other components of the simulation need their own
state as well. Therefore, I refactored the `SimulationState` type a bit,
to make it more extensible. Instead of using hardcoded type numbers, a
string is used to identify the state type. Also, instead of having switch
statements in many places, there is a new `SimulationStateType` that
encapsulates information about how a specific state is created/freed/copied/...

I removed the integration with the point cache for now, because it was
not used anyway in it's current state.

1 files changed, 1 insertions, 86 deletions

diff --git a/source/blender/blenkernel/intern/pointcache.c b/source/blender/blenkernel/intern/pointcache.c
index aa93c6cb854..4b09f7542c7 100644
--- a/source/blender/blenkernel/intern/pointcache.c
+++ b/source/blender/blenkernel/intern/pointcache.c
@@ -1885,81 +1885,6 @@ void BKE_ptcache_id_from_rigidbody(PTCacheID *pid, Object *ob, RigidBodyWorld *r
   pid->file_type = PTCACHE_FILE_PTCACHE;
 }
 
-static int ptcache_sim_particle_totpoint(void *state_v, int UNUSED(cfra))
-{
-  ParticleSimulationState *state = (ParticleSimulationState *)state_v;
-  return state->tot_particles;
-}
-
-static void ptcache_sim_particle_error(void *UNUSED(state_v), const char *UNUSED(message))
-{
-}
-
-static int ptcache_sim_particle_write(int index, void *state_v, void **data, int UNUSED(cfra))
-{
-  ParticleSimulationState *state = (ParticleSimulationState *)state_v;
-
-  const float *positions = (const float *)CustomData_get_layer_named(
-      &state->attributes, CD_PROP_FLOAT3, "Position");
-
-  PTCACHE_DATA_FROM(data, BPHYS_DATA_LOCATION, positions + (index * 3));
-
-  return 1;
-}
-static void ptcache_sim_particle_read(
-    int index, void *state_v, void **data, float UNUSED(cfra), const float *UNUSED(old_data))
-{
-  ParticleSimulationState *state = (ParticleSimulationState *)state_v;
-
-  BLI_assert(index < state->tot_particles);
-  float *positions = (float *)CustomData_get_layer_named(
-      &state->attributes, CD_PROP_FLOAT3, "Position");
-
-  PTCACHE_DATA_TO(data, BPHYS_DATA_LOCATION, 0, positions + (index * 3));
-}
-
-void BKE_ptcache_id_from_sim_particles(PTCacheID *pid,
-                                       ParticleSimulationState *state_orig,
-                                       ParticleSimulationState *state_cow)
-{
-  memset(pid, 0, sizeof(PTCacheID));
-
-  pid->calldata = state_cow;
-  pid->type = PTCACHE_TYPE_SIM_PARTICLES;
-  pid->cache = state_orig->point_cache;
-  pid->cache_ptr = &state_orig->point_cache;
-  pid->ptcaches = &state_orig->ptcaches;
-  pid->totpoint = ptcache_sim_particle_totpoint;
-  pid->totwrite = ptcache_sim_particle_totpoint;
-  pid->error = ptcache_sim_particle_error;
-
-  pid->write_point = ptcache_sim_particle_write;
-  pid->read_point = ptcache_sim_particle_read;
-  pid->interpolate_point = NULL;
-
-  pid->write_stream = NULL;
-  pid->read_stream = NULL;
-
-  pid->write_openvdb_stream = NULL;
-  pid->read_openvdb_stream = NULL;
-
-  pid->write_extra_data = NULL;
-  pid->read_extra_data = NULL;
-  pid->interpolate_extra_data = NULL;
-
-  pid->write_header = NULL;
-  pid->read_header = NULL;
-
-  pid->data_types = 1 << BPHYS_DATA_LOCATION;
-  pid->info_types = 0;
-
-  pid->stack_index = 0;
-
-  pid->default_step = 1;
-  pid->max_step = 1;
-  pid->file_type = PTCACHE_FILE_PTCACHE;
-}
-
 /**
  * \param ob: Optional, may be NULL.
  * \param scene: Optional may be NULL.
@@ -2059,17 +1984,7 @@ static bool foreach_object_modifier_ptcache(Object *object,
       }
     }
     else if (md->type == eModifierType_Simulation) {
-      SimulationModifierData *smd = (SimulationModifierData *)md;
-      if (smd->simulation) {
-        LISTBASE_FOREACH (SimulationState *, state, &smd->simulation->states) {
-          switch ((eSimulationStateType)state->type) {
-            case SIM_STATE_TYPE_PARTICLES: {
-              /* TODO(jacques) */
-              break;
-            }
-          }
-        }
-      }
+      /* TODO(jacques) */
     }
   }
   return true;