1HEADmaster

1 files changed, 312 insertions, 0 deletions

diff --git a/mathlib/lightdesc.cpp b/mathlib/lightdesc.cpp
new file mode 100644
index 0000000..7d69282
--- /dev/null
+++ b/mathlib/lightdesc.cpp
@@ -0,0 +1,312 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+//=====================================================================================//
+
+#include <ssemath.h>
+#include <lightdesc.h>
+#include "mathlib.h"
+
+void LightDesc_t::RecalculateDerivedValues(void)
+{
+	m_Flags = LIGHTTYPE_OPTIMIZATIONFLAGS_DERIVED_VALUES_CALCED;
+	if (m_Attenuation0)
+		m_Flags|=LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION0;
+	if (m_Attenuation1)
+		m_Flags|=LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION1;
+	if (m_Attenuation2)
+		m_Flags|=LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION2;
+	
+	if (m_Type==MATERIAL_LIGHT_SPOT)
+	{
+		m_ThetaDot=cos(m_Theta);
+		m_PhiDot=cos(m_Phi);
+		float spread=m_ThetaDot-m_PhiDot;
+		if (spread>1.0e-10)
+		{
+			// note - this quantity is very sensitive to round off error. the sse
+			// reciprocal approximation won't cut it here.
+			OneOver_ThetaDot_Minus_PhiDot=1.0/spread;
+		}
+		else
+		{
+			// hard falloff instead of divide by zero
+			OneOver_ThetaDot_Minus_PhiDot=1.0;
+		}				
+	}	
+	if (m_Type==MATERIAL_LIGHT_DIRECTIONAL)
+	{
+		// set position to be real far away in the right direction
+		m_Position=m_Direction;
+		m_Position *= 2.0e6;
+	}
+	
+	m_RangeSquared=m_Range*m_Range;
+
+}
+
+void LightDesc_t::ComputeLightAtPointsForDirectional(
+	const FourVectors &pos, const FourVectors &normal,
+	FourVectors &color, bool DoHalfLambert ) const
+{
+	FourVectors delta;
+	delta.DuplicateVector(m_Direction);
+//	delta.VectorNormalizeFast();
+	fltx4 strength=delta*normal;
+	if (DoHalfLambert)
+	{
+		strength=AddSIMD(MulSIMD(strength,Four_PointFives),Four_PointFives);
+	}
+	else
+		strength=MaxSIMD(Four_Zeros,delta*normal);
+		
+	color.x=AddSIMD(color.x,MulSIMD(strength,ReplicateX4(m_Color.x)));
+	color.y=AddSIMD(color.y,MulSIMD(strength,ReplicateX4(m_Color.y)));
+	color.z=AddSIMD(color.z,MulSIMD(strength,ReplicateX4(m_Color.z)));
+}
+
+
+void LightDesc_t::ComputeLightAtPoints( const FourVectors &pos, const FourVectors &normal,
+										FourVectors &color, bool DoHalfLambert ) const
+{
+	FourVectors delta;
+	Assert((m_Type==MATERIAL_LIGHT_POINT) || (m_Type==MATERIAL_LIGHT_SPOT) || (m_Type==MATERIAL_LIGHT_DIRECTIONAL));
+	switch (m_Type)
+	{
+		case MATERIAL_LIGHT_POINT:
+		case MATERIAL_LIGHT_SPOT:
+			delta.DuplicateVector(m_Position);
+			delta-=pos;
+			break;
+				
+		case MATERIAL_LIGHT_DIRECTIONAL:
+			ComputeLightAtPointsForDirectional( pos, normal, color, DoHalfLambert );
+			return;
+	}
+
+	fltx4 dist2 = delta*delta;
+
+	dist2=MaxSIMD( Four_Ones, dist2 );
+
+	fltx4 falloff;
+
+	if( m_Flags & LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION0 )
+	{
+		falloff = ReplicateX4(m_Attenuation0);
+	}
+	else
+		falloff= Four_Epsilons;
+
+	if( m_Flags & LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION1 )
+	{
+		falloff=AddSIMD(falloff,MulSIMD(ReplicateX4(m_Attenuation1),SqrtEstSIMD(dist2)));
+	}
+
+	if( m_Flags & LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION2 )
+	{
+		falloff=AddSIMD(falloff,MulSIMD(ReplicateX4(m_Attenuation2),dist2));
+	}
+
+	falloff=ReciprocalEstSIMD(falloff);
+	// Cull out light beyond this radius
+	// now, zero out elements for which dist2 was > range^2. !!speed!! lights should store dist^2 in sse format
+	if (m_Range != 0.f)
+	{
+		fltx4 RangeSquared=ReplicateX4(m_RangeSquared); // !!speed!!
+		falloff=AndSIMD(falloff,CmpLtSIMD(dist2,RangeSquared));
+	}
+
+	delta.VectorNormalizeFast();
+	fltx4 strength=delta*normal;
+	if (DoHalfLambert)
+	{
+		strength=AddSIMD(MulSIMD(strength,Four_PointFives),Four_PointFives);
+	}
+	else
+		strength=MaxSIMD(Four_Zeros,delta*normal);
+		
+	switch(m_Type)
+	{
+		case MATERIAL_LIGHT_POINT:
+			// half-lambert
+			break;
+				
+		case MATERIAL_LIGHT_SPOT:
+		{
+			fltx4 dot2=SubSIMD(Four_Zeros,delta*m_Direction); // dot position with spot light dir for cone falloff
+
+
+			fltx4 cone_falloff_scale=MulSIMD(ReplicateX4(OneOver_ThetaDot_Minus_PhiDot),
+												 SubSIMD(dot2,ReplicateX4(m_PhiDot)));
+			cone_falloff_scale=MinSIMD(cone_falloff_scale,Four_Ones);
+			
+			if ((m_Falloff!=0.0) && (m_Falloff!=1.0))
+			{
+				// !!speed!! could compute integer exponent needed by powsimd and store in light
+				cone_falloff_scale=PowSIMD(cone_falloff_scale,m_Falloff);
+			}
+			strength=MulSIMD(cone_falloff_scale,strength);
+
+			// now, zero out lighting where dot2<phidot. This will mask out any invalid results
+			// from pow function, etc
+			fltx4 OutsideMask=CmpGtSIMD(dot2,ReplicateX4(m_PhiDot)); // outside light cone?
+			strength=AndSIMD(OutsideMask,strength);
+		}
+		break;
+			
+
+	}
+	strength=MulSIMD(strength,falloff);
+	color.x=AddSIMD(color.x,MulSIMD(strength,ReplicateX4(m_Color.x)));
+	color.y=AddSIMD(color.y,MulSIMD(strength,ReplicateX4(m_Color.y)));
+	color.z=AddSIMD(color.z,MulSIMD(strength,ReplicateX4(m_Color.z)));
+}
+
+
+
+void LightDesc_t::ComputeNonincidenceLightAtPoints( const FourVectors &pos, FourVectors &color ) const
+{
+	FourVectors delta;
+	Assert((m_Type==MATERIAL_LIGHT_POINT) || (m_Type==MATERIAL_LIGHT_SPOT) || (m_Type==MATERIAL_LIGHT_DIRECTIONAL));
+	switch (m_Type)
+	{
+		case MATERIAL_LIGHT_POINT:
+		case MATERIAL_LIGHT_SPOT:
+			delta.DuplicateVector(m_Position);
+			delta-=pos;
+			break;
+				
+		case MATERIAL_LIGHT_DIRECTIONAL:
+			return;
+	}
+
+	fltx4 dist2 = delta*delta;
+
+	dist2=MaxSIMD( Four_Ones, dist2 );
+
+	fltx4 falloff;
+
+	if( m_Flags & LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION0 )
+	{
+		falloff = ReplicateX4(m_Attenuation0);
+	}
+	else
+		falloff= Four_Epsilons;
+
+	if( m_Flags & LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION1 )
+	{
+		falloff=AddSIMD(falloff,MulSIMD(ReplicateX4(m_Attenuation1),SqrtEstSIMD(dist2)));
+	}
+
+	if( m_Flags & LIGHTTYPE_OPTIMIZATIONFLAGS_HAS_ATTENUATION2 )
+	{
+		falloff=AddSIMD(falloff,MulSIMD(ReplicateX4(m_Attenuation2),dist2));
+	}
+
+	falloff=ReciprocalEstSIMD(falloff);
+	// Cull out light beyond this radius
+	// now, zero out elements for which dist2 was > range^2. !!speed!! lights should store dist^2 in sse format
+	if (m_Range != 0.f)
+	{
+		fltx4 RangeSquared=ReplicateX4(m_RangeSquared); // !!speed!!
+		falloff=AndSIMD(falloff,CmpLtSIMD(dist2,RangeSquared));
+	}
+
+	delta.VectorNormalizeFast();
+	fltx4 strength = Four_Ones;
+	//fltx4 strength=delta;
+	//fltx4 strength = MaxSIMD(Four_Zeros,delta);
+		
+	switch(m_Type)
+	{
+		case MATERIAL_LIGHT_POINT:
+			// half-lambert
+			break;
+				
+		case MATERIAL_LIGHT_SPOT:
+		{
+			fltx4 dot2=SubSIMD(Four_Zeros,delta*m_Direction); // dot position with spot light dir for cone falloff
+
+
+			fltx4 cone_falloff_scale=MulSIMD(ReplicateX4(OneOver_ThetaDot_Minus_PhiDot),
+												 SubSIMD(dot2,ReplicateX4(m_PhiDot)));
+			cone_falloff_scale=MinSIMD(cone_falloff_scale,Four_Ones);
+			
+			if ((m_Falloff!=0.0) && (m_Falloff!=1.0))
+			{
+				// !!speed!! could compute integer exponent needed by powsimd and store in light
+				cone_falloff_scale=PowSIMD(cone_falloff_scale,m_Falloff);
+			}
+			strength=MulSIMD(cone_falloff_scale,strength);
+
+			// now, zero out lighting where dot2<phidot. This will mask out any invalid results
+			// from pow function, etc
+			fltx4 OutsideMask=CmpGtSIMD(dot2,ReplicateX4(m_PhiDot)); // outside light cone?
+			strength=AndSIMD(OutsideMask,strength);
+		}
+		break;
+			
+
+	}
+	strength=MulSIMD(strength,falloff);
+	color.x=AddSIMD(color.x,MulSIMD(strength,ReplicateX4(m_Color.x)));
+	color.y=AddSIMD(color.y,MulSIMD(strength,ReplicateX4(m_Color.y)));
+	color.z=AddSIMD(color.z,MulSIMD(strength,ReplicateX4(m_Color.z)));
+}
+
+
+
+void LightDesc_t::SetupOldStyleAttenuation( float fQuadraticAttn, float fLinearAttn, float fConstantAttn )
+{
+	// old-style manually typed quadrtiac coefficients
+	if ( fQuadraticAttn < EQUAL_EPSILON )
+		fQuadraticAttn = 0;
+	
+	if ( fLinearAttn < EQUAL_EPSILON)
+		fLinearAttn = 0;
+	
+	if ( fConstantAttn < EQUAL_EPSILON)
+		fConstantAttn = 0;
+	
+	if ( ( fConstantAttn < EQUAL_EPSILON ) && 
+		 ( fLinearAttn < EQUAL_EPSILON ) && 
+		 ( fQuadraticAttn < EQUAL_EPSILON ) )
+		fConstantAttn = 1;
+
+	m_Attenuation2=fQuadraticAttn;
+	m_Attenuation1=fLinearAttn;
+	m_Attenuation0=fConstantAttn;
+	float fScaleFactor = fQuadraticAttn * 10000 + fLinearAttn * 100 + fConstantAttn;
+	
+	if ( fScaleFactor > 0 )
+		m_Color *= fScaleFactor;
+}
+
+void LightDesc_t::SetupNewStyleAttenuation( float fFiftyPercentDistance, 
+											float fZeroPercentDistance )
+{
+	// new style storing 50% and 0% distances
+	float d50=fFiftyPercentDistance;
+	float d0=fZeroPercentDistance;
+	if (d0<d50)
+	{
+		// !!warning in lib code???!!!
+		Warning("light has _fifty_percent_distance of %f but no zero_percent_distance\n",d50);
+		d0=2.0*d50;
+	}
+	float a=0,b=1,c=0;
+	if (! SolveInverseQuadraticMonotonic(0,1.0,d50,2.0,d0,256.0,a,b,c))
+	{
+		Warning("can't solve quadratic for light %f %f\n",d50,d0);
+	}
+	float v50=c+d50*(b+d50*a);
+	float scale=2.0/v50;
+	a*=scale;
+	b*=scale;
+	c*=scale;
+	m_Attenuation2=a;
+	m_Attenuation1=b;
+	m_Attenuation0=c;
+}
+