void AddEmitSurfaceLights( const Vector &vStart, Vector lightBoxColor[6] )
{
fltx4 fractionVisible;
FourVectors vStart4, wlOrigin4;
vStart4.DuplicateVector ( vStart );
for ( int iLight=0; iLight < *pNumworldlights; iLight++ )
{
dworldlight_t *wl = &dworldlights[iLight];
// Should this light even go in the ambient cubes?
if ( !( wl->flags & DWL_FLAGS_INAMBIENTCUBE ) )
continue;
Assert( wl->type == emit_surface );
// Can this light see the point?
wlOrigin4.DuplicateVector ( wl->origin );
TestLine ( vStart4, wlOrigin4, &fractionVisible );
if ( !TestSignSIMD ( CmpGtSIMD ( fractionVisible, Four_Zeros ) ) )
continue;
// Add this light's contribution.
Vector vDelta = wl->origin - vStart;
float flDistanceScale = Engine_WorldLightDistanceFalloff( wl, vDelta );
Vector vDeltaNorm = vDelta;
VectorNormalize( vDeltaNorm );
float flAngleScale = Engine_WorldLightAngle( wl, wl->normal, vDeltaNorm, vDeltaNorm );
float ratio = flDistanceScale * flAngleScale * SubFloat ( fractionVisible, 0 );
if ( ratio == 0 )
continue;
for ( int i=0; i < 6; i++ )
{
float t = DotProduct( g_BoxDirections[i], vDeltaNorm );
if ( t > 0 )
{
lightBoxColor[i] += wl->intensity * (t * ratio);
}
}
}
}
void RayTracingEnvironment::RenderScene(
int width, int height, // width and height of desired rendering
int stride, // actual width in pixels of target buffer
uint32 *output_buffer, // pointer to destination
Vector CameraOrigin, // eye position
Vector ULCorner, // word space coordinates of upper left
// monitor corner
Vector URCorner, // top right corner
Vector LLCorner, // lower left
Vector LRCorner, // lower right
RayTraceLightingMode_t lmode)
{
// first, compute deltas
Vector dxvector=URCorner;
dxvector-=ULCorner;
dxvector*=(1.0/width);
Vector dxvectortimes2=dxvector;
dxvectortimes2+=dxvector;
Vector dyvector=LLCorner;
dyvector-=ULCorner;
dyvector*=(1.0/height);
// block_offsets-relative offsets for eahc of the 4 pixels in the block, in sse format
FourVectors block_offsets;
block_offsets.LoadAndSwizzle(Vector(0,0,0),dxvector,dyvector,dxvector+dyvector);
FourRays myrays;
myrays.origin.DuplicateVector(CameraOrigin);
// tmprays is used fo rthe case when we cannot trace 4 rays at once.
FourRays tmprays;
tmprays.origin.DuplicateVector(CameraOrigin);
// now, we will ray trace pixels. we will do the rays in a 2x2 pattern
for(int y=0;y<height;y+=2)
{
Vector SLoc=dyvector;
SLoc*=((float) y);
SLoc+=ULCorner;
uint32 *dest=output_buffer+y*stride;
for(int x=0;x<width;x+=2)
{
myrays.direction.DuplicateVector(SLoc);
myrays.direction+=block_offsets;
myrays.direction.VectorNormalize();
RayTracingResult rslt;
Trace4Rays(myrays,all_zeros,TraceLimit, &rslt);
if ((rslt.HitIds[0]==-1) && (rslt.HitIds[1]==-1) &&
(rslt.HitIds[2]==-1) && (rslt.HitIds[3]==-1))
MapLinearIntensities(BackgroundColor,dest,dest+1,dest+stride,dest+stride+1);
else
{
// make sure normal points back towards ray origin
fltx4 ndoti=rslt.surface_normal*myrays.direction;
fltx4 bad_dirs=AndSIMD(CmpGtSIMD(ndoti,Four_Zeros),
LoadAlignedSIMD((float *) signmask));
// flip signs of all "wrong" normals
rslt.surface_normal.x=XorSIMD(bad_dirs,rslt.surface_normal.x);
rslt.surface_normal.y=XorSIMD(bad_dirs,rslt.surface_normal.y);
rslt.surface_normal.z=XorSIMD(bad_dirs,rslt.surface_normal.z);
FourVectors intens;
intens.DuplicateVector(Vector(0,0,0));
// set up colors
FourVectors surf_colors;
surf_colors.DuplicateVector(Vector(0,0,0));
for(int i=0;i<4;i++)
{
if (rslt.HitIds[i]>=0)
{
surf_colors.X(i)=TriangleColors[rslt.HitIds[i]].x;
surf_colors.Y(i)=TriangleColors[rslt.HitIds[i]].y;
surf_colors.Z(i)=TriangleColors[rslt.HitIds[i]].z;
}
}
FourVectors surface_pos=myrays.direction;
surface_pos*=rslt.HitDistance;
surface_pos+=myrays.origin;
switch(lmode)
{
case DIRECT_LIGHTING:
{
// light all points
for(int l=0;l<LightList.Count();l++)
{
LightList[l].ComputeLightAtPoints(surface_pos,rslt.surface_normal,
intens);
}
}
break;
case DIRECT_LIGHTING_WITH_SHADOWS:
{
// light all points
for(int l=0;l<LightList.Count();l++)
{
FourVectors ldir;
ldir.DuplicateVector(LightList[l].m_Position);
ldir-=surface_pos;
fltx4 MaxT=ldir.length();
ldir.VectorNormalizeFast();
// now, compute shadow flag
FourRays myrays;
myrays.origin=surface_pos;
FourVectors epsilon=ldir;
epsilon*=0.01;
myrays.origin+=epsilon;
myrays.direction=ldir;
RayTracingResult shadowtest;
Trace4Rays(myrays,Four_Zeros,MaxT, &shadowtest);
fltx4 unshadowed=CmpGtSIMD(shadowtest.HitDistance,MaxT);
if (! (IsAllZeros(unshadowed)))
{
FourVectors tmp;
tmp.DuplicateVector(Vector(0,0,0));
LightList[l].ComputeLightAtPoints(surface_pos,rslt.surface_normal,
tmp);
intens.x=AddSIMD(intens.x,AndSIMD(tmp.x,unshadowed));
intens.y=AddSIMD(intens.y,AndSIMD(tmp.y,unshadowed));
intens.z=AddSIMD(intens.z,AndSIMD(tmp.z,unshadowed));
}
}
}
break;
}
// now, mask off non-hitting pixels
intens.VProduct(surf_colors);
fltx4 no_hit_mask=CmpGtSIMD(rslt.HitDistance,TraceLimit);
intens.x=OrSIMD(AndSIMD(BackgroundColor.x,no_hit_mask),
AndNotSIMD(no_hit_mask,intens.x));
intens.y=OrSIMD(AndSIMD(BackgroundColor.y,no_hit_mask),
AndNotSIMD(no_hit_mask,intens.y));
intens.z=OrSIMD(AndSIMD(BackgroundColor.y,no_hit_mask),
AndNotSIMD(no_hit_mask,intens.z));
MapLinearIntensities(intens,dest,dest+1,dest+stride,dest+stride+1);
}
dest+=2;
SLoc+=dxvectortimes2;
}
}
}
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;
default:
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(m_OneOverThetaDotMinusPhiDot),
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;
default:
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 RayTracingEnvironment::ComputeVirtualLightSources(void)
{
int start_pos=0;
for(int b=0;b<3;b++)
{
int nl=LightList.Count();
int where_to_start=start_pos;
start_pos=nl;
for(int l=where_to_start;l<nl;l++)
{
DirectionalSampler_t sample_generator;
int n_desired=1*LightList[l].m_Color.Length();
if (LightList[l].m_Type==MATERIAL_LIGHT_SPOT)
n_desired*=LightList[l].m_Phi/2;
for(int try1=0;try1<n_desired;try1++)
{
LightDesc_t const &li=LightList[l];
FourRays myrays;
myrays.origin.DuplicateVector(li.m_Position);
RayTracingResult rslt;
Vector trial_dir=sample_generator.NextValue();
if (li.IsDirectionWithinLightCone(trial_dir))
{
myrays.direction.DuplicateVector(trial_dir);
Trace4Rays(myrays,all_zeros,ReplicateX4(1000.0), &rslt);
if ((rslt.HitIds[0]!=-1))
{
// make sure normal points back towards ray origin
fltx4 ndoti=rslt.surface_normal*myrays.direction;
fltx4 bad_dirs=AndSIMD(CmpGtSIMD(ndoti,Four_Zeros),
LoadAlignedSIMD((float *) signmask));
// flip signs of all "wrong" normals
rslt.surface_normal.x=XorSIMD(bad_dirs,rslt.surface_normal.x);
rslt.surface_normal.y=XorSIMD(bad_dirs,rslt.surface_normal.y);
rslt.surface_normal.z=XorSIMD(bad_dirs,rslt.surface_normal.z);
// a hit! let's make a virtual light source
// treat the virtual light as a disk with its center at the hit position
// and its radius scaled by the amount of the solid angle this probe
// represents.
float area_of_virtual_light=
4.0*M_PI*SQ( SubFloat( rslt.HitDistance, 0 ) )*(1.0/n_desired);
FourVectors intens;
intens.DuplicateVector(Vector(0,0,0));
FourVectors surface_pos=myrays.direction;
surface_pos*=rslt.HitDistance;
surface_pos+=myrays.origin;
FourVectors delta=rslt.surface_normal;
delta*=0.1;
surface_pos+=delta;
LightList[l].ComputeLightAtPoints(surface_pos,rslt.surface_normal,
intens);
FourVectors surf_colors;
surf_colors.DuplicateVector(TriangleColors[rslt.HitIds[0]]);
intens*=surf_colors;
// see if significant
LightDesc_t l1;
l1.m_Type=MATERIAL_LIGHT_SPOT;
l1.m_Position=Vector(surface_pos.X(0),surface_pos.Y(0),surface_pos.Z(0));
l1.m_Direction=Vector(rslt.surface_normal.X(0),rslt.surface_normal.Y(0),
rslt.surface_normal.Z(0));
l1.m_Color=Vector(intens.X(0),intens.Y(0),intens.Z(0));
if (l1.m_Color.Length()>0)
{
l1.m_Color*=area_of_virtual_light/M_PI;
l1.m_Range=0.0;
l1.m_Falloff=1.0;
l1.m_Attenuation0=1.0;
l1.m_Attenuation1=0.0;
l1.m_Attenuation2=1.0; // intens falls off as 1/r^2
l1.m_Theta=0;
l1.m_Phi=M_PI;
l1.RecalculateDerivedValues();
LightList.AddToTail(l1);
}
}
}
}
}
}
}
void RayTracingEnvironment::Trace4Rays(const FourRays &rays, fltx4 TMin, fltx4 TMax,
int DirectionSignMask, RayTracingResult *rslt_out,
int32 skip_id, ITransparentTriangleCallback *pCallback)
{
rays.Check();
memset(rslt_out->HitIds,0xff,sizeof(rslt_out->HitIds));
rslt_out->HitDistance=ReplicateX4(1.0e23);
rslt_out->surface_normal.DuplicateVector(Vector(0.,0.,0.));
FourVectors OneOverRayDir=rays.direction;
OneOverRayDir.MakeReciprocalSaturate();
// now, clip rays against bounding box
for(int c=0;c<3;c++)
{
fltx4 isect_min_t=
MulSIMD(SubSIMD(ReplicateX4(m_MinBound[c]),rays.origin[c]),OneOverRayDir[c]);
fltx4 isect_max_t=
MulSIMD(SubSIMD(ReplicateX4(m_MaxBound[c]),rays.origin[c]),OneOverRayDir[c]);
TMin=MaxSIMD(TMin,MinSIMD(isect_min_t,isect_max_t));
TMax=MinSIMD(TMax,MaxSIMD(isect_min_t,isect_max_t));
}
fltx4 active=CmpLeSIMD(TMin,TMax); // mask of which rays are active
if (! IsAnyNegative(active) )
return; // missed bounding box
int32 mailboxids[MAILBOX_HASH_SIZE]; // used to avoid redundant triangle tests
memset(mailboxids,0xff,sizeof(mailboxids)); // !!speed!! keep around?
int front_idx[3],back_idx[3]; // based on ray direction, whether to
// visit left or right node first
if (DirectionSignMask & 1)
{
back_idx[0]=0;
front_idx[0]=1;
}
else
{
back_idx[0]=1;
front_idx[0]=0;
}
if (DirectionSignMask & 2)
{
back_idx[1]=0;
front_idx[1]=1;
}
else
{
back_idx[1]=1;
front_idx[1]=0;
}
if (DirectionSignMask & 4)
{
back_idx[2]=0;
front_idx[2]=1;
}
else
{
back_idx[2]=1;
front_idx[2]=0;
}
NodeToVisit NodeQueue[MAX_NODE_STACK_LEN];
CacheOptimizedKDNode const *CurNode=&(OptimizedKDTree[0]);
NodeToVisit *stack_ptr=&NodeQueue[MAX_NODE_STACK_LEN];
while(1)
{
while (CurNode->NodeType() != KDNODE_STATE_LEAF) // traverse until next leaf
{
int split_plane_number=CurNode->NodeType();
CacheOptimizedKDNode const *FrontChild=&(OptimizedKDTree[CurNode->LeftChild()]);
fltx4 dist_to_sep_plane= // dist=(split-org)/dir
MulSIMD(
SubSIMD(ReplicateX4(CurNode->SplittingPlaneValue),
rays.origin[split_plane_number]),OneOverRayDir[split_plane_number]);
fltx4 active=CmpLeSIMD(TMin,TMax); // mask of which rays are active
// now, decide how to traverse children. can either do front,back, or do front and push
// back.
fltx4 hits_front=AndSIMD(active,CmpGeSIMD(dist_to_sep_plane,TMin));
if (! IsAnyNegative(hits_front))
{
// missed the front. only traverse back
//printf("only visit back %d\n",CurNode->LeftChild()+back_idx[split_plane_number]);
CurNode=FrontChild+back_idx[split_plane_number];
TMin=MaxSIMD(TMin, dist_to_sep_plane);
}
else
{
fltx4 hits_back=AndSIMD(active,CmpLeSIMD(dist_to_sep_plane,TMax));
if (! IsAnyNegative(hits_back) )
{
// missed the back - only need to traverse front node
//printf("only visit front %d\n",CurNode->LeftChild()+front_idx[split_plane_number]);
CurNode=FrontChild+front_idx[split_plane_number];
TMax=MinSIMD(TMax, dist_to_sep_plane);
}
else
{
// at least some rays hit both nodes.
// must push far, traverse near
//printf("visit %d,%d\n",CurNode->LeftChild()+front_idx[split_plane_number],
// CurNode->LeftChild()+back_idx[split_plane_number]);
assert(stack_ptr>NodeQueue);
--stack_ptr;
stack_ptr->node=FrontChild+back_idx[split_plane_number];
stack_ptr->TMin=MaxSIMD(TMin,dist_to_sep_plane);
stack_ptr->TMax=TMax;
CurNode=FrontChild+front_idx[split_plane_number];
TMax=MinSIMD(TMax,dist_to_sep_plane);
}
}
}
// hit a leaf! must do intersection check
int ntris=CurNode->NumberOfTrianglesInLeaf();
if (ntris)
{
int32 const *tlist=&(TriangleIndexList[CurNode->TriangleIndexStart()]);
do
{
int tnum=*(tlist++);
//printf("try tri %d\n",tnum);
// check mailbox
int mbox_slot=tnum & (MAILBOX_HASH_SIZE-1);
TriIntersectData_t const *tri = &( OptimizedTriangleList[tnum].m_Data.m_IntersectData );
if ( ( mailboxids[mbox_slot] != tnum ) && ( tri->m_nTriangleID != skip_id ) )
{
n_intersection_calculations++;
mailboxids[mbox_slot] = tnum;
// compute plane intersection
FourVectors N;
N.x = ReplicateX4( tri->m_flNx );
N.y = ReplicateX4( tri->m_flNy );
N.z = ReplicateX4( tri->m_flNz );
fltx4 DDotN = rays.direction * N;
// mask off zero or near zero (ray parallel to surface)
fltx4 did_hit = OrSIMD( CmpGtSIMD( DDotN,FourEpsilons ),
CmpLtSIMD( DDotN, FourNegativeEpsilons ) );
fltx4 numerator=SubSIMD( ReplicateX4( tri->m_flD ), rays.origin * N );
fltx4 isect_t=DivSIMD( numerator,DDotN );
// now, we have the distance to the plane. lets update our mask
did_hit = AndSIMD( did_hit, CmpGtSIMD( isect_t, FourZeros ) );
//did_hit=AndSIMD(did_hit,CmpLtSIMD(isect_t,TMax));
did_hit = AndSIMD( did_hit, CmpLtSIMD( isect_t, rslt_out->HitDistance ) );
if ( ! IsAnyNegative( did_hit ) )
continue;
// now, check 3 edges
fltx4 hitc1 = AddSIMD( rays.origin[tri->m_nCoordSelect0],
MulSIMD( isect_t, rays.direction[ tri->m_nCoordSelect0] ) );
fltx4 hitc2 = AddSIMD( rays.origin[tri->m_nCoordSelect1],
MulSIMD( isect_t, rays.direction[tri->m_nCoordSelect1] ) );
// do barycentric coordinate check
fltx4 B0 = MulSIMD( ReplicateX4( tri->m_ProjectedEdgeEquations[0] ), hitc1 );
B0 = AddSIMD(
B0,
MulSIMD( ReplicateX4( tri->m_ProjectedEdgeEquations[1] ), hitc2 ) );
B0 = AddSIMD(
B0, ReplicateX4( tri->m_ProjectedEdgeEquations[2] ) );
did_hit = AndSIMD( did_hit, CmpGeSIMD( B0, FourZeros ) );
fltx4 B1 = MulSIMD( ReplicateX4( tri->m_ProjectedEdgeEquations[3] ), hitc1 );
B1 = AddSIMD(
B1,
MulSIMD( ReplicateX4( tri->m_ProjectedEdgeEquations[4]), hitc2 ) );
B1 = AddSIMD(
B1, ReplicateX4( tri->m_ProjectedEdgeEquations[5] ) );
did_hit = AndSIMD( did_hit, CmpGeSIMD( B1, FourZeros ) );
fltx4 B2 = AddSIMD( B1, B0 );
did_hit = AndSIMD( did_hit, CmpLeSIMD( B2, Four_Ones ) );
if ( ! IsAnyNegative( did_hit ) )
continue;
// if the triangle is transparent
if ( tri->m_nFlags & FCACHETRI_TRANSPARENT )
{
if ( pCallback )
{
// assuming a triangle indexed as v0, v1, v2
// the projected edge equations are set up such that the vert opposite the first
// equation is v2, and the vert opposite the second equation is v0
// Therefore we pass them back in 1, 2, 0 order
// Also B2 is currently B1 + B0 and needs to be 1 - (B1+B0) in order to be a real
// barycentric coordinate. Compute that now and pass it to the callback
fltx4 b2 = SubSIMD( Four_Ones, B2 );
if ( pCallback->VisitTriangle_ShouldContinue( *tri, rays, &did_hit, &B1, &b2, &B0, tnum ) )
{
did_hit = Four_Zeros;
}
}
}
// now, set the hit_id and closest_hit fields for any enabled rays
fltx4 replicated_n = ReplicateIX4(tnum);
StoreAlignedSIMD((float *) rslt_out->HitIds,
OrSIMD(AndSIMD(replicated_n,did_hit),
AndNotSIMD(did_hit,LoadAlignedSIMD(
(float *) rslt_out->HitIds))));
rslt_out->HitDistance=OrSIMD(AndSIMD(isect_t,did_hit),
AndNotSIMD(did_hit,rslt_out->HitDistance));
rslt_out->surface_normal.x=OrSIMD(
AndSIMD(N.x,did_hit),
AndNotSIMD(did_hit,rslt_out->surface_normal.x));
rslt_out->surface_normal.y=OrSIMD(
AndSIMD(N.y,did_hit),
AndNotSIMD(did_hit,rslt_out->surface_normal.y));
rslt_out->surface_normal.z=OrSIMD(
AndSIMD(N.z,did_hit),
AndNotSIMD(did_hit,rslt_out->surface_normal.z));
}
} while (--ntris);
// now, check if all rays have terminated
fltx4 raydone=CmpLeSIMD(TMax,rslt_out->HitDistance);
if (! IsAnyNegative(raydone))
{
return;
}
}
if (stack_ptr==&NodeQueue[MAX_NODE_STACK_LEN])
{
return;
}
// pop stack!
CurNode=stack_ptr->node;
TMin=stack_ptr->TMin;
TMax=stack_ptr->TMax;
stack_ptr++;
}
}
