source-engine/particles/builtin_particle_emitters.cpp
FluorescentCIAAfricanAmerican 3bf9df6b27 1
2020-04-22 12:56:21 -04:00

877 lines
29 KiB
C++

//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: particle system code
//
//===========================================================================//
#include "tier0/platform.h"
#include "particles/particles.h"
#include "filesystem.h"
#include "tier2/tier2.h"
#include "tier2/fileutils.h"
#include "tier1/UtlStringMap.h"
#include "tier1/strtools.h"
// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"
extern int g_nParticle_Multiplier;
//-----------------------------------------------------------------------------
// Emits particles immediately
//-----------------------------------------------------------------------------
struct InstantaneousEmitterContext_t
{
int m_nRemainingParticles;
int m_ActualParticlesToEmit;
float m_flTimeOffset;
bool m_bReadScaleFactor;
};
class C_OP_InstantaneousEmitter : public CParticleOperatorInstance
{
DECLARE_PARTICLE_OPERATOR( C_OP_InstantaneousEmitter );
uint32 GetWrittenAttributes( void ) const
{
return PARTICLE_ATTRIBUTE_CREATION_TIME_MASK;
}
uint32 GetReadAttributes( void ) const
{
return 0;
}
virtual uint64 GetReadControlPointMask() const
{
if ( m_nScaleControlPoint >= 0 )
return ( 1ULL << m_nScaleControlPoint );
return 0;
}
virtual uint32 Emit( CParticleCollection *pParticles, float flCurStrength,
void *pContext ) const;
// unpack structure will be applied by creator. add extra initialization needed here
virtual void InitParams( CParticleSystemDefinition *pDef, CDmxElement *pElement )
{
if ( m_nMinParticlesToEmit >= 0 )
{
if ( m_nMinParticlesToEmit > m_nParticlesToEmit )
{
V_swap( m_nParticlesToEmit, m_nMinParticlesToEmit );
}
}
if ( m_nPerFrameNum < 0 )
{
m_nPerFrameNum = INT_MAX;
}
m_nScaleControlPointField = clamp( m_nScaleControlPointField, 0, 2 );
}
virtual void StopEmission( CParticleCollection *pParticles, void *pContext, bool bInfiniteOnly ) const
{
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
if ( !bInfiniteOnly )
{
pCtx->m_nRemainingParticles = 0;
}
}
virtual void StartEmission( CParticleCollection *pParticles, void *pContext, bool bInfiniteOnly ) const
{
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
if ( !bInfiniteOnly )
{
pCtx->m_nRemainingParticles = pCtx->m_ActualParticlesToEmit;
SkipToTime( pParticles->m_flCurTime, pParticles, pCtx );
}
}
// Called when the SFM wants to skip forward in time
virtual void SkipToTime( float flTime, CParticleCollection *pParticles, void *pContext ) const
{
// NOTE: This is a bit of a hack. We're saying that if we're skipping more than two seconds, that we're
// probably not going to bother emitting at all. Really, this would have to know the maximum
// lifetime of the child particles and only skip if past that.
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( flTime > ( flStartTime + 2.0f ) )
{
pCtx->m_nRemainingParticles = 0;
}
}
virtual void InitializeContextData( CParticleCollection *pParticles, void *pContext ) const
{
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
if ( m_nMinParticlesToEmit >= 0 )
{
pCtx->m_ActualParticlesToEmit = pParticles->RandomInt( m_nMinParticlesToEmit, m_nParticlesToEmit );
}
else
{
pCtx->m_ActualParticlesToEmit = m_nParticlesToEmit;
}
pCtx->m_nRemainingParticles = pCtx->m_ActualParticlesToEmit;
pCtx->m_flTimeOffset = 0.0f;
pCtx->m_bReadScaleFactor = false;
}
virtual void Restart( CParticleCollection *pParticles, void *pContext )
{
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
pCtx->m_nRemainingParticles = pCtx->m_ActualParticlesToEmit;
pCtx->m_flTimeOffset = pParticles->m_flCurTime;
pCtx->m_bReadScaleFactor = false;
}
size_t GetRequiredContextBytes( void ) const
{
return sizeof( InstantaneousEmitterContext_t );
}
virtual bool MayCreateMoreParticles( CParticleCollection *pParticles, void *pContext ) const
{
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
return !(pCtx->m_nRemainingParticles <= 0);
}
int m_nParticlesToEmit;
int m_nMinParticlesToEmit;
float m_flStartTime;
int m_nPerFrameNum;
int m_nScaleControlPoint;
int m_nScaleControlPointField;
};
DEFINE_PARTICLE_OPERATOR( C_OP_InstantaneousEmitter, "emit_instantaneously", OPERATOR_GENERIC );
BEGIN_PARTICLE_OPERATOR_UNPACK( C_OP_InstantaneousEmitter )
DMXELEMENT_UNPACK_FIELD( "emission_start_time", "0", float, m_flStartTime )
DMXELEMENT_UNPACK_FIELD( "num_to_emit_minimum", "-1", int, m_nMinParticlesToEmit )
DMXELEMENT_UNPACK_FIELD( "num_to_emit", "100", int, m_nParticlesToEmit )
DMXELEMENT_UNPACK_FIELD( "maximum emission per frame", "-1", int, m_nPerFrameNum )
DMXELEMENT_UNPACK_FIELD( "emission count scale control point", "-1", int, m_nScaleControlPoint )
DMXELEMENT_UNPACK_FIELD( "emission count scale control point field", "0", int, m_nScaleControlPointField )
END_PARTICLE_OPERATOR_UNPACK( C_OP_InstantaneousEmitter )
uint32 C_OP_InstantaneousEmitter::Emit( CParticleCollection *pParticles, float flCurStrength,
void *pContext ) const
{
// Don't emit any more if the particle system has emitted all it's supposed to.
InstantaneousEmitterContext_t *pCtx = reinterpret_cast<InstantaneousEmitterContext_t *>( pContext );
if ( pCtx->m_nRemainingParticles <= 0 )
return 0;
// Wait until we're told to start emitting
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( pParticles->m_flCurTime < flStartTime )
return 0;
if ( pCtx->m_ActualParticlesToEmit == 0 )
return 0;
if ( ( m_nScaleControlPoint >= 0 ) && !pCtx->m_bReadScaleFactor )
{
Vector vecScale;
if ( flStartTime <= pParticles->m_flCurTime && flStartTime >= pParticles->m_flCurTime - pParticles->m_flPreviousDt )
{
pParticles->GetControlPointAtTime( m_nScaleControlPoint, flStartTime, &vecScale );
}
else
{
pParticles->GetControlPointAtPrevTime( m_nScaleControlPoint, &vecScale );
}
pCtx->m_ActualParticlesToEmit *= vecScale[m_nScaleControlPointField];
pCtx->m_nRemainingParticles *= vecScale[m_nScaleControlPointField];
pCtx->m_bReadScaleFactor = true;
}
pCtx->m_nRemainingParticles = max( pCtx->m_nRemainingParticles, 0 );
// NOTE: Applying the scale here because I don't believe we can sample the control point
// values inside
// We're only allowed to emit so many particles, though..
// If we run out of room, only emit the last N particles
int nAllowedParticlesToEmit = pParticles->m_nMaxAllowedParticles - pParticles->m_nActiveParticles;
// Cap to the maximum emission per frame
int nParticlesThisFrame = min( m_nPerFrameNum, pCtx->m_nRemainingParticles );
nAllowedParticlesToEmit = min( nAllowedParticlesToEmit, nParticlesThisFrame );
int nActualParticlesToEmit = min( nAllowedParticlesToEmit, pCtx->m_ActualParticlesToEmit * g_nParticle_Multiplier );
pCtx->m_nRemainingParticles -= nParticlesThisFrame;
Assert( pCtx->m_nRemainingParticles >= 0 );
if ( nActualParticlesToEmit == 0 )
return 0;
int nStartParticle = pParticles->m_nActiveParticles;
pParticles->SetNActiveParticles( nActualParticlesToEmit + pParticles->m_nActiveParticles );
// !! speed!! do sse init here
for( int i = nStartParticle; i < nStartParticle + nActualParticlesToEmit; i++ )
{
float *pTimeStamp = pParticles->GetFloatAttributePtrForWrite( PARTICLE_ATTRIBUTE_CREATION_TIME, i );
*pTimeStamp = flStartTime;
}
return PARTICLE_ATTRIBUTE_CREATION_TIME_MASK;
}
//-----------------------------------------------------------------------------
// Emits particles over time
//-----------------------------------------------------------------------------
struct ContinuousEmitterContext_t
{
float m_flTotalActualParticlesSoFar;
int m_nTotalEmittedSoFar;
float m_flNextEmitTime;
float m_flTimeOffset;
bool m_bStoppedEmission;
};
bool g_bDontMakeSkipToTimeTakeForever = false;
class C_OP_ContinuousEmitter : public CParticleOperatorInstance
{
DECLARE_PARTICLE_OPERATOR( C_OP_ContinuousEmitter );
uint32 GetWrittenAttributes( void ) const
{
return PARTICLE_ATTRIBUTE_CREATION_TIME_MASK;
}
uint32 GetReadAttributes( void ) const
{
return 0;
}
virtual void InitParams( CParticleSystemDefinition *pDef, CDmxElement *pElement )
{
if ( m_flEmitRate < 0.0f )
{
m_flEmitRate = 0.0f;
}
if ( m_flEmissionDuration < 0.0f )
{
m_flEmissionDuration = 0.0f;
}
m_flEmitRate *= g_nParticle_Multiplier;
}
virtual uint32 Emit( CParticleCollection *pParticles, float flCurStrength,
void *pContext ) const ;
inline bool IsInfinitelyEmitting() const
{
return ( m_flEmissionDuration == 0.0f );
}
virtual void StopEmission( CParticleCollection *pParticles, void *pContext, bool bInfiniteOnly ) const
{
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
if ( !bInfiniteOnly || IsInfinitelyEmitting() )
{
pCtx->m_bStoppedEmission = true;
}
}
virtual void StartEmission( CParticleCollection *pParticles, void *pContext, bool bInfiniteOnly ) const
{
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
if ( !bInfiniteOnly || IsInfinitelyEmitting() )
{
pCtx->m_bStoppedEmission = false;
SkipToTime( pParticles->m_flCurTime, pParticles, pCtx );
}
}
virtual void InitializeContextData( CParticleCollection *pParticles, void *pContext ) const
{
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
pCtx->m_flNextEmitTime = m_flStartTime;
pCtx->m_flTotalActualParticlesSoFar = 0.0f;
pCtx->m_nTotalEmittedSoFar = 0;
pCtx->m_flTimeOffset = 0.0f;
pCtx->m_bStoppedEmission = false;
}
virtual void Restart( CParticleCollection *pParticles, void *pContext )
{
if ( !IsInfinitelyEmitting() )
{
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
pCtx->m_flNextEmitTime = pParticles->m_flCurTime + m_flStartTime;
pCtx->m_flTotalActualParticlesSoFar = 0.0f;
pCtx->m_nTotalEmittedSoFar = 0;
pCtx->m_flTimeOffset = pParticles->m_flCurTime;
}
}
// Called when the SFM wants to skip forward in time
// Currently hacked for save/load pre-sim - correct solution is to serialize rather
// than skip-to-time and simulate
virtual void SkipToTime( float flTime, CParticleCollection *pParticles, void *pContext ) const
{
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( flTime <= flStartTime )
return;
float flControlPointScale = pParticles->GetHighestControlPoint();
flControlPointScale *= m_flEmissionScale;
float flEmissionRate = m_flEmitRate;
float flEmitStrength;
if ( pParticles->CheckIfOperatorShouldRun( this, &flEmitStrength ) )
{
flEmissionRate *= flEmitStrength;
}
if ( flControlPointScale != 0.0f )
{
flEmissionRate *= flControlPointScale;
}
float flPrevDrawTime = pParticles->m_flCurTime - flTime;
float flCurrDrawTime = pParticles->m_flCurTime;
if ( !IsInfinitelyEmitting() )
{
if ( flPrevDrawTime < flStartTime )
{
flPrevDrawTime = flStartTime;
}
//if ( flCurrDrawTime > flStartTime + m_flEmissionDuration )
//{
// flCurrDrawTime = flStartTime + m_flEmissionDuration;
//}
}
float flDeltaTime = flCurrDrawTime - flPrevDrawTime;
flDeltaTime = min( flDeltaTime, 4.f );
flPrevDrawTime = flCurrDrawTime - flDeltaTime;
//disabled for now
pCtx->m_flTotalActualParticlesSoFar = flDeltaTime * flEmissionRate;
//if ( !IsInfinitelyEmitting() )
// pCtx->m_flTotalActualParticlesSoFar = min( pCtx->m_ActualParticlesToEmit, pCtx->m_flTotalActualParticlesSoFar );
pCtx->m_nTotalEmittedSoFar = 0;
//simulate a bunch
int nActualParticlesToEmit = floor (pCtx->m_flTotalActualParticlesSoFar);
int nStartParticle = pParticles->m_nActiveParticles;
if ( pParticles->m_nMaxAllowedParticles < nStartParticle + nActualParticlesToEmit )
{
nActualParticlesToEmit = pParticles->m_nMaxAllowedParticles - nStartParticle;
}
pParticles->SetNActiveParticles( nActualParticlesToEmit + pParticles->m_nActiveParticles );
float flTimeStampStep = ( flDeltaTime ) / ( nActualParticlesToEmit );
float flTimeStep = flPrevDrawTime + flTimeStampStep;
// Set the particle creation time to the exact sub-frame particle emission time
// !! speed!! do sse init here
for( int i = nStartParticle; i < nStartParticle + nActualParticlesToEmit; i++ )
{
float *pTimeStamp = pParticles->GetFloatAttributePtrForWrite( PARTICLE_ATTRIBUTE_CREATION_TIME, i );
flTimeStep = min( flTimeStep, flCurrDrawTime );
*pTimeStamp = flTimeStep;
flTimeStep += flTimeStampStep;
}
if ( !g_bDontMakeSkipToTimeTakeForever )
{
flPrevDrawTime = max( flPrevDrawTime, flCurrDrawTime - pParticles->m_pDef->m_flNoDrawTimeToGoToSleep );
pParticles->m_flCurTime = flPrevDrawTime;
pParticles->m_fl4CurTime = ReplicateX4( flPrevDrawTime );
for( float i = flPrevDrawTime; i < flCurrDrawTime; i += 0.1 )
{
pParticles->Simulate( .1, false );
}
}
}
size_t GetRequiredContextBytes( void ) const
{
return sizeof( ContinuousEmitterContext_t );
}
virtual bool MayCreateMoreParticles( CParticleCollection *pParticles, void *pContext ) const
{
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
if ( pCtx->m_bStoppedEmission )
return false;
if ( m_flEmitRate <= 0.0f )
return false;
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( m_flEmissionDuration != 0.0f && ( pParticles->m_flCurTime - pParticles->m_flDt ) > ( flStartTime + m_flEmissionDuration ) )
return false;
return true;
}
float m_flEmissionDuration;
float m_flStartTime;
float m_flEmitRate;
float m_flTimePerEmission;
float m_flEmissionScale;
bool m_bScalePerParticle;
};
DEFINE_PARTICLE_OPERATOR( C_OP_ContinuousEmitter, "emit_continuously", OPERATOR_GENERIC );
BEGIN_PARTICLE_OPERATOR_UNPACK( C_OP_ContinuousEmitter )
DMXELEMENT_UNPACK_FIELD( "emission_start_time", "0", float, m_flStartTime )
DMXELEMENT_UNPACK_FIELD( "emission_rate", "100", float, m_flEmitRate )
DMXELEMENT_UNPACK_FIELD( "emission_duration", "0", float, m_flEmissionDuration )
DMXELEMENT_UNPACK_FIELD( "scale emission to used control points", "0.0", float, m_flEmissionScale )
DMXELEMENT_UNPACK_FIELD( "use parent particles for emission scaling", "0", bool, m_bScalePerParticle )
END_PARTICLE_OPERATOR_UNPACK( C_OP_ContinuousEmitter )
uint32 C_OP_ContinuousEmitter::Emit( CParticleCollection *pParticles, float flCurStrength,
void *pContext ) const
{
// Have we emitted all the particles we're going to emit?
// NOTE: Using C_OP_ContinuousEmitter:: avoids a virtual function call
ContinuousEmitterContext_t *pCtx = reinterpret_cast<ContinuousEmitterContext_t *>( pContext );
//Allows for dynamic scaling via changes in number of control points.
float flControlPointScale = pParticles->GetHighestControlPoint();
//The emission scale here allows for a scalar value per controlpoint, like 2 or .25...
flControlPointScale *= m_flEmissionScale;
//Global strength scale brought in by operator fade in/fade out/oscillate
float flEmissionRate = m_flEmitRate * flCurStrength;
if ( flControlPointScale != 0.0f || m_bScalePerParticle )
{
if ( m_bScalePerParticle )
{
if ( pParticles->m_pParent )
{
flControlPointScale = pParticles->m_pParent->m_nActiveParticles * m_flEmissionScale;
}
else
{
flControlPointScale = m_flEmissionScale;
}
}
flEmissionRate *= flControlPointScale;
}
if ( flEmissionRate == 0.0f )
return 0;
if ( !C_OP_ContinuousEmitter::MayCreateMoreParticles( pParticles, pContext ) )
return 0;
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( pParticles->m_flCurTime < flStartTime )
return 0;
Assert( flEmissionRate != 0.0f );
// determine our previous and current draw times and clamp them to start time and emission duration
float flPrevDrawTime = pParticles->m_flCurTime - pParticles->m_flDt;
float flCurrDrawTime = pParticles->m_flCurTime;
if ( !IsInfinitelyEmitting() )
{
if ( flPrevDrawTime < flStartTime )
{
flPrevDrawTime = flStartTime;
}
if ( flCurrDrawTime > flStartTime + m_flEmissionDuration )
{
flCurrDrawTime = flStartTime + m_flEmissionDuration;
}
}
float flDeltaTime = flCurrDrawTime - flPrevDrawTime;
//Calculate emission rate by delta time from last frame to determine number of particles to emit this frame as a fractional float
float flActualParticlesToEmit = flEmissionRate * flDeltaTime;
//Add emitted particle to float counter to allow for fractional emission
pCtx->m_flTotalActualParticlesSoFar += flActualParticlesToEmit;
//Floor float accumulated value and subtract whole int emitted so far from the result to determine total whole particles to emit this frame
int nParticlesToEmit = floor ( pCtx->m_flTotalActualParticlesSoFar ) - pCtx->m_nTotalEmittedSoFar;
//Add emitted particles to running int total.
pCtx->m_nTotalEmittedSoFar += nParticlesToEmit;
if ( nParticlesToEmit == 0 )
return 0;
// We're only allowed to emit so many particles, though..
// If we run out of room, only emit the last N particles
int nActualParticlesToEmit = nParticlesToEmit;
int nAllowedParticlesToEmit = pParticles->m_nMaxAllowedParticles - pParticles->m_nActiveParticles;
if ( nAllowedParticlesToEmit < nParticlesToEmit )
{
nActualParticlesToEmit = nAllowedParticlesToEmit;
//flStartEmissionTime = pCtx->m_flNextEmitTime - flTimePerEmission * nActualParticlesToEmit;
}
if ( nActualParticlesToEmit == 0 )
return 0;
int nStartParticle = pParticles->m_nActiveParticles;
pParticles->SetNActiveParticles( nActualParticlesToEmit + pParticles->m_nActiveParticles );
float flTimeStampStep = ( flDeltaTime ) / ( nActualParticlesToEmit );
float flTimeStep = flPrevDrawTime + flTimeStampStep;
// Set the particle creation time to the exact sub-frame particle emission time
// !! speed!! do sse init here
for( int i = nStartParticle; i < nStartParticle + nActualParticlesToEmit; i++ )
{
float *pTimeStamp = pParticles->GetFloatAttributePtrForWrite( PARTICLE_ATTRIBUTE_CREATION_TIME, i );
flTimeStep = min( flTimeStep, flCurrDrawTime );
*pTimeStamp = flTimeStep;
flTimeStep += flTimeStampStep;
}
return PARTICLE_ATTRIBUTE_CREATION_TIME_MASK;
}
//-----------------------------------------------------------------------------
// Noise Emitter
//-----------------------------------------------------------------------------
struct NoiseEmitterContext_t
{
float m_flTotalActualParticlesSoFar;
int m_nTotalEmittedSoFar;
float m_flNextEmitTime;
float m_flTimeOffset;
bool m_bStoppedEmission;
};
class C_OP_NoiseEmitter : public CParticleOperatorInstance
{
DECLARE_PARTICLE_OPERATOR( C_OP_NoiseEmitter );
uint32 GetWrittenAttributes( void ) const
{
return PARTICLE_ATTRIBUTE_CREATION_TIME_MASK;
}
uint32 GetReadAttributes( void ) const
{
return 0;
}
virtual void InitParams( CParticleSystemDefinition *pDef, CDmxElement *pElement )
{
if ( m_flEmitRate < 0.0f )
{
m_flEmitRate = 0.0f;
}
if ( m_flEmissionDuration < 0.0f )
{
m_flEmissionDuration = 0.0f;
}
m_flEmitRate *= g_nParticle_Multiplier;
}
virtual uint32 Emit( CParticleCollection *pParticles, float flCurStrength,
void *pContext ) const ;
inline bool IsInfinitelyEmitting() const
{
return ( m_flEmissionDuration == 0.0f );
}
virtual void StopEmission( CParticleCollection *pParticles, void *pContext, bool bInfiniteOnly ) const
{
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
if ( !bInfiniteOnly || IsInfinitelyEmitting() )
{
pCtx->m_bStoppedEmission = true;
}
}
virtual void StartEmission( CParticleCollection *pParticles, void *pContext, bool bInfiniteOnly ) const
{
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
if ( !bInfiniteOnly || IsInfinitelyEmitting() )
{
pCtx->m_bStoppedEmission = false;
SkipToTime( pParticles->m_flCurTime, pParticles, pCtx );
}
}
virtual void InitializeContextData( CParticleCollection *pParticles, void *pContext ) const
{
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
pCtx->m_flNextEmitTime = m_flStartTime;
pCtx->m_flTotalActualParticlesSoFar = 1.0f;
pCtx->m_nTotalEmittedSoFar = 0;
pCtx->m_flTimeOffset = 0.0f;
pCtx->m_bStoppedEmission = false;
}
virtual void Restart( CParticleCollection *pParticles, void *pContext )
{
if ( !IsInfinitelyEmitting() )
{
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
pCtx->m_flNextEmitTime = m_flStartTime + pParticles->m_flCurTime;
pCtx->m_flTotalActualParticlesSoFar = 1.0f;
pCtx->m_nTotalEmittedSoFar = 0;
pCtx->m_flTimeOffset = pParticles->m_flCurTime;
}
}
// Called when the SFM wants to skip forward in time
virtual void SkipToTime( float flTime, CParticleCollection *pParticles, void *pContext ) const
{
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( flTime <= flStartTime )
return;
float flControlPointScale = pParticles->GetHighestControlPoint();
flControlPointScale *= m_flEmissionScale;
float flEmissionRate = m_flEmitRate;
float flEmitStrength;
if ( pParticles->CheckIfOperatorShouldRun( this, &flEmitStrength ) )
{
flEmissionRate *= flEmitStrength;
}
if ( flControlPointScale != 0.0f )
{
flEmissionRate *= flControlPointScale;
}
pCtx->m_flTotalActualParticlesSoFar = ( pParticles->m_flCurTime - flStartTime ) * flEmissionRate + 1;
//if ( !IsInfinitelyEmitting() )
// pCtx->m_flTotalActualParticlesSoFar = min( pCtx->m_ActualParticlesToEmit, pCtx->m_flTotalActualParticlesSoFar );
pCtx->m_nTotalEmittedSoFar = 0;
}
size_t GetRequiredContextBytes( void ) const
{
return sizeof( NoiseEmitterContext_t );
}
virtual bool MayCreateMoreParticles( CParticleCollection *pParticles, void *pContext ) const
{
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
if ( pCtx->m_bStoppedEmission )
return false;
if ( m_flEmitRate <= 0.0f )
return false;
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( m_flEmissionDuration != 0.0f && ( pParticles->m_flCurTime - pParticles->m_flDt ) > ( flStartTime + m_flEmissionDuration ) )
return false;
return true;
}
float m_flEmissionDuration;
float m_flStartTime;
float m_flEmitRate;
float m_flTimePerEmission;
float m_flEmissionScale;
bool m_bAbsVal, m_bAbsValInv;
float m_flOffset;
float m_flOutputMin;
float m_flOutputMax;
float m_flNoiseScale, m_flNoiseScaleLoc;
Vector m_vecOffsetLoc;
float m_flWorldTimeScale;
};
DEFINE_PARTICLE_OPERATOR( C_OP_NoiseEmitter, "emit noise", OPERATOR_GENERIC );
BEGIN_PARTICLE_OPERATOR_UNPACK( C_OP_NoiseEmitter )
DMXELEMENT_UNPACK_FIELD( "emission_start_time", "0", float, m_flStartTime )
DMXELEMENT_UNPACK_FIELD( "emission_duration", "0", float, m_flEmissionDuration )
DMXELEMENT_UNPACK_FIELD( "scale emission to used control points", "0.0", float, m_flEmissionScale )
DMXELEMENT_UNPACK_FIELD( "time noise coordinate scale","0.1",float,m_flNoiseScale)
//DMXELEMENT_UNPACK_FIELD( "spatial noise coordinate scale","0.001",float,m_flNoiseScaleLoc)
DMXELEMENT_UNPACK_FIELD( "time coordinate offset","0", float, m_flOffset )
//DMXELEMENT_UNPACK_FIELD( "spatial coordinate offset","0 0 0", Vector, m_vecOffsetLoc )
DMXELEMENT_UNPACK_FIELD( "absolute value","0", bool, m_bAbsVal )
DMXELEMENT_UNPACK_FIELD( "invert absolute value","0", bool, m_bAbsValInv )
DMXELEMENT_UNPACK_FIELD( "emission minimum","0", float, m_flOutputMin )
DMXELEMENT_UNPACK_FIELD( "emission maximum","100", float, m_flOutputMax )
DMXELEMENT_UNPACK_FIELD( "world time noise coordinate scale","0", float, m_flWorldTimeScale )
END_PARTICLE_OPERATOR_UNPACK( C_OP_NoiseEmitter )
uint32 C_OP_NoiseEmitter::Emit( CParticleCollection *pParticles, float flCurStrength,
void *pContext ) const
{
// Have we emitted all the particles we're going to emit?
// NOTE: Using C_OP_ContinuousEmitter:: avoids a virtual function call
NoiseEmitterContext_t *pCtx = reinterpret_cast<NoiseEmitterContext_t *>( pContext );
//Allows for dynamic scaling via changes in number of control points.
float flControlPointScale = pParticles->GetHighestControlPoint();
//The emission scale here allows for a scalar value per controlpoint, like 2 or .25...
flControlPointScale *= m_flEmissionScale;
float flAbsScale;
int nAbsVal;
nAbsVal = 0xffffffff;
flAbsScale = 0.5;
if ( m_bAbsVal )
{
nAbsVal = 0x7fffffff;
flAbsScale = 1.0;
}
float fMin = m_flOutputMin;
float fMax = m_flOutputMax;
float CoordScale = m_flNoiseScale;
//float CoordScaleLoc = m_flNoiseScaleLoc;
float ValueScale, ValueBase;
Vector Coord, CoordLoc, CoordWorldTime;
//CoordLoc.x = pxyz[0];
//CoordLoc.y = pxyz[4];
//CoordLoc.z = pxyz[8];
//CoordLoc += m_vecOffsetLoc;
float Offset = m_flOffset;
Coord = Vector ( (pParticles->m_flCurTime + Offset), (pParticles->m_flCurTime + Offset), (pParticles->m_flCurTime + Offset) );
Coord *= CoordScale;
//CoordLoc *= CoordScaleLoc;
//Coord += CoordLoc;
CoordWorldTime = Vector( (Plat_MSTime() * m_flWorldTimeScale), (Plat_MSTime() * m_flWorldTimeScale), (Plat_MSTime() * m_flWorldTimeScale) );
Coord += CoordWorldTime;
fltx4 flNoise128;
FourVectors fvNoise;
fvNoise.DuplicateVector( Coord );
flNoise128 = NoiseSIMD( fvNoise );
float flNoise = SubFloat( flNoise128, 0 );
*( (int *) &flNoise) &= nAbsVal;
ValueScale = ( flAbsScale *( fMax - fMin ) );
ValueBase = ( fMin+ ( ( 1.0 - flAbsScale ) *( fMax - fMin ) ) );
if ( m_bAbsValInv )
{
flNoise = 1.0 - flNoise;
}
float flInitialNoise = ( ValueBase + ( ValueScale * flNoise ) );
flInitialNoise = clamp(flInitialNoise, 0.0f, (float) INT_MAX );
//Global strength scale brought in by operator fade in/fade out/oscillate
float flEmissionRate = flInitialNoise * flCurStrength;
if ( flControlPointScale != 0.0f )
{
flEmissionRate *= flControlPointScale;
}
if ( flEmissionRate == 0.0f )
return 0;
if ( !C_OP_NoiseEmitter::MayCreateMoreParticles( pParticles, pContext ) )
return 0;
float flStartTime = m_flStartTime + pCtx->m_flTimeOffset;
if ( pParticles->m_flCurTime < flStartTime )
return 0;
Assert( flEmissionRate != 0.0f );
// determine our previous and current draw times and clamp them to start time and emission duration
float flPrevDrawTime = pParticles->m_flCurTime - pParticles->m_flDt;
float flCurrDrawTime = pParticles->m_flCurTime;
if ( !IsInfinitelyEmitting() )
{
if ( flPrevDrawTime < flStartTime )
{
flPrevDrawTime = flStartTime;
}
if ( flCurrDrawTime > flStartTime + m_flEmissionDuration )
{
flCurrDrawTime = flStartTime + m_flEmissionDuration;
}
}
float flDeltaTime = flCurrDrawTime - flPrevDrawTime;
//Calculate emission rate by delta time from last frame to determine number of particles to emit this frame as a fractional float
float flActualParticlesToEmit = flEmissionRate * flDeltaTime;
//Add emitted particle to float counter to allow for fractional emission
pCtx->m_flTotalActualParticlesSoFar += flActualParticlesToEmit;
//Floor float accumulated value and subtract whole int emitted so far from the result to determine total whole particles to emit this frame
int nParticlesToEmit = floor ( pCtx->m_flTotalActualParticlesSoFar ) - pCtx->m_nTotalEmittedSoFar;
//Add emitted particles to running int total.
pCtx->m_nTotalEmittedSoFar += nParticlesToEmit;
if ( nParticlesToEmit == 0 )
return 0;
// We're only allowed to emit so many particles, though..
// If we run out of room, only emit the last N particles
int nActualParticlesToEmit = nParticlesToEmit;
int nAllowedParticlesToEmit = pParticles->m_nMaxAllowedParticles - pParticles->m_nActiveParticles;
if ( nAllowedParticlesToEmit < nParticlesToEmit )
{
nActualParticlesToEmit = nAllowedParticlesToEmit;
//flStartEmissionTime = pCtx->m_flNextEmitTime - flTimePerEmission * nActualParticlesToEmit;
}
if ( nActualParticlesToEmit == 0 )
return 0;
int nStartParticle = pParticles->m_nActiveParticles;
pParticles->SetNActiveParticles( nActualParticlesToEmit + pParticles->m_nActiveParticles );
float flTimeStampStep = ( flCurrDrawTime - flPrevDrawTime ) / ( nActualParticlesToEmit );
float flTimeStep = flPrevDrawTime + flTimeStampStep;
// Set the particle creation time to the exact sub-frame particle emission time
// !! speed!! do sse init here
for( int i = nStartParticle; i < nStartParticle + nActualParticlesToEmit; i++ )
{
float *pTimeStamp = pParticles->GetFloatAttributePtrForWrite( PARTICLE_ATTRIBUTE_CREATION_TIME, i );
flTimeStep = min( flTimeStep, flCurrDrawTime );
*pTimeStamp = flTimeStep;
flTimeStep += flTimeStampStep;
}
return PARTICLE_ATTRIBUTE_CREATION_TIME_MASK;
}
void AddBuiltInParticleEmitters( void )
{
REGISTER_PARTICLE_OPERATOR( FUNCTION_EMITTER, C_OP_ContinuousEmitter );
REGISTER_PARTICLE_OPERATOR( FUNCTION_EMITTER, C_OP_InstantaneousEmitter );
REGISTER_PARTICLE_OPERATOR( FUNCTION_EMITTER, C_OP_NoiseEmitter );
}