/** Look for dead particles and move from the end of the list to the dead location, compacting in the process
*/
void FNiagaraSimulation::KillParticles()
{
SCOPE_CYCLE_COUNTER(STAT_NiagaraKill);
int32 OrigNumParticles = Data.GetNumInstances();
int32 CurNumParticles = OrigNumParticles;
int32 ParticleIndex = OrigNumParticles - 1;
if (bGenerateDeathEvents)
{
DeathEventGenerator.BeginTrackingDeaths();
}
const FVector4* ParticleRelativeTimes = Data.GetVariableData(FNiagaraVariableInfo(BUILTIN_VAR_PARTICLEAGE, ENiagaraDataType::Vector));
if (ParticleRelativeTimes)
{
while (ParticleIndex >= 0)
{
if (ParticleRelativeTimes[ParticleIndex].X > 1.0f)
{
if (bGenerateDeathEvents)
{
DeathEventGenerator.OnDeath(ParticleIndex);
}
check(CurNumParticles > ParticleIndex);
// Particle is dead, move one from the end here.
MoveParticleToIndex(--CurNumParticles, ParticleIndex);
}
--ParticleIndex;
}
}
Data.SetNumInstances(CurNumParticles);
if (bGenerateDeathEvents)
{
DeathEventGenerator.EndTrackingDeaths();
}
// check if the emitter has officially died
if (GetTickState() == NTS_Dieing && CurNumParticles == 0)
{
SetTickState(NTS_Dead);
}
}
void FNiagaraSimulation::PreTick()
{
UNiagaraEmitterProperties* PinnedProps = Props.Get();
if (!PinnedProps || !bIsEnabled || TickState == NTS_Suspended || TickState == NTS_Dead)
return;
check(Data.GetNumVariables() > 0);
check(PinnedProps->SpawnScriptProps.Script);
check(PinnedProps->UpdateScriptProps.Script);
// Iterate over looking for dead particles and move from the end of the list to the dead location, compacting in the process
{
SCOPE_CYCLE_COUNTER(STAT_NiagaraKill);
int32 OrigNumParticles = Data.GetNumInstances();
int32 CurNumParticles = OrigNumParticles;
int32 ParticleIndex = OrigNumParticles-1;
if (bGenerateDeathEvents)
{
DeathEventGenerator.BeginTrackingDeaths();
}
const FVector4* ParticleRelativeTimes = Data.GetVariableData(FNiagaraVariableInfo(FName(TEXT("Age")), ENiagaraDataType::Vector));
if (ParticleRelativeTimes)
{
while (ParticleIndex >= 0)
{
if (ParticleRelativeTimes[ParticleIndex].X > 1.0f)
{
if (bGenerateDeathEvents)
{
DeathEventGenerator.OnDeath(ParticleIndex);
}
check(CurNumParticles > ParticleIndex);
// Particle is dead, move one from the end here.
MoveParticleToIndex(--CurNumParticles, ParticleIndex);
DebuggerHook_OnDeath(this, ParticleIndex, CurNumParticles);
}
--ParticleIndex;
}
}
Data.SetNumInstances(CurNumParticles);
if (bGenerateDeathEvents)
{
DeathEventGenerator.EndTrackingDeaths();
}
// check if the emitter has officially died
if (GetTickState() == NTS_Dieing && CurNumParticles == 0)
{
SetTickState(NTS_Dead);
}
}
//Swap all data set buffers before doing the main tick on any simulation.
for (TPair<FNiagaraDataSetID, FNiagaraDataSet*> SetPair : DataSetMap)
{
SetPair.Value->Tick();
}
}
void FNiagaraSimulation::Tick(float DeltaSeconds)
{
SCOPE_CYCLE_COUNTER(STAT_NiagaraTick);
if (!bIsEnabled || TickState==NTS_Suspended || TickState==NTS_Dead)
return;
SimpleTimer TickTime;
check(Data.GetNumAttributes() > 0);
check(Props->SpawnScript);
check(Props->UpdateScript);
// Cache the ComponentToWorld transform.
// CachedComponentToWorld = Component.GetComponentToWorld();
Data.SwapBuffers();
Data.SetNumParticles(Data.GetPrevNumParticles());
int32 OrigNumParticles = Data.GetNumParticles();
int32 NumToSpawn = 0;
// Figure out how many we will spawn.
NumToSpawn = CalcNumToSpawn(DeltaSeconds);
int32 MaxNewParticles = OrigNumParticles + NumToSpawn;
Data.Allocate(MaxNewParticles);
Age += DeltaSeconds;
Constants.SetOrAdd(TEXT("Emitter Age"), FVector4(Age, Age, Age, Age));
Constants.SetOrAdd(TEXT("Delta Time"), FVector4(DeltaSeconds, DeltaSeconds, DeltaSeconds, DeltaSeconds));
// Simulate particles forward by DeltaSeconds.
if (TickState==NTS_Running || TickState==NTS_Dieing)
{
SCOPE_CYCLE_COUNTER(STAT_NiagaraSimulate);
RunVMScript(Props->UpdateScript, EUnusedAttributeBehaviour::Copy);
}
//Init new particles with the spawn script.
if (TickState==NTS_Running)
{
SCOPE_CYCLE_COUNTER(STAT_NiagaraSpawn);
Data.SetNumParticles(MaxNewParticles);
//For now, zero any unused attributes here. But as this is really uninitialized data we should maybe make this a more serious error.
RunVMScript(Props->SpawnScript, EUnusedAttributeBehaviour::Zero, OrigNumParticles, NumToSpawn);
}
// Iterate over looking for dead particles and move from the end of the list to the dead location, compacting in the process
{
SCOPE_CYCLE_COUNTER(STAT_NiagaraKill);
int32 CurNumParticles = OrigNumParticles = Data.GetNumParticles();
int32 ParticleIndex = 0;
const FVector4* ParticleRelativeTimes = Data.GetAttributeData(FNiagaraVariableInfo(FName(TEXT("Age")), ENiagaraDataType::Vector));
if (ParticleRelativeTimes)
{
while (ParticleIndex < OrigNumParticles)
{
if (ParticleRelativeTimes[ParticleIndex].X > 1.0f)
{
// Particle is dead, move one from the end here.
MoveParticleToIndex(--CurNumParticles, ParticleIndex);
}
ParticleIndex++;
}
}
Data.SetNumParticles(CurNumParticles);
// check if the emitter has officially died
if (GetTickState() == NTS_Dieing && CurNumParticles == 0)
{
SetTickState(NTS_Dead);
}
}
CPUTimeMS = TickTime.GetElapsedMilliseconds();
DECLARE_DWORD_COUNTER_STAT(TEXT("NumParticles"), STAT_NiagaraNumParticles, STATGROUP_Niagara);
INC_DWORD_STAT_BY(STAT_NiagaraNumParticles, Data.GetNumParticles());
}
