Files
VoxelForge/Standalone/Core/src/FarShellsInternal.h
T
Fr0zkaandClaude Opus 5.5 61633cb492 wip(assembler): M1 round 6 -- owner walk fixes: 25 cm geometry scale, one height datum, carve/fill sign, faster relief meshing
Owner saw content floating above native terrain, spiky triangles, reversed carve/fill and late relief.
Causes: shared mesher placed Core tiles on a 12.5 cm grid; content/atmosphere asked strate ranges in
12.5 cm voxels; Core edits add density where the legacy diff subtracts. Horizon LOD8 bridge edge
5.657 -> 2.265 cells. Relief mesh p95 60.8 -> 42.0 ms (LOD0). New BuildHost checks for scale, height,
blueprint carve/fill and per-kind streaming lag.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
2026-10-09 20:39:24 +02:00

1070 lines
57 KiB
C++

#pragma once
#include "OwnerWorldLoader.h"
#include "StandaloneShapeWorld.h"
#include "VoxelTypes.h"
#include <algorithm>
#include <array>
#include <cmath>
#include <cstdint>
#include <limits>
#include <memory>
#include <type_traits>
#include <utility>
#include <vector>
struct FFarMeshSegmentIndex
{
FFarMeshSegmentIndex(const FVoxelMeshData& InMesh,const FIntVector& InOrigin,int32 InExtent,
int32 InCells,double InStep)
:Mesh(InMesh),Origin(InOrigin),Extent(InExtent),Cells(std::max(1,InCells)),Step(InStep),
ByCell(static_cast<size_t>(Cells)*Cells*Cells),
TriangleMarks(static_cast<size_t>(InMesh.Triangles.Num()/3),0)
{
for(int32 Triangle=0;Triangle+2<Mesh.Triangles.Num();Triangle+=3)
{
const int32 A=Mesh.Triangles[Triangle],B=Mesh.Triangles[Triangle+1],C=Mesh.Triangles[Triangle+2];
if(A<0||B<0||C<0||A>=Mesh.Vertices.Num()||B>=Mesh.Vertices.Num()||C>=Mesh.Vertices.Num())continue;
int32 Lo[3],Hi[3];
for(int32 Axis=0;Axis<3;++Axis)
{
const double VA=PositionAxis(A,Axis),VB=PositionAxis(B,Axis),VC=PositionAxis(C,Axis);
Lo[Axis]=CellFor(std::min({VA,VB,VC}),Axis);
Hi[Axis]=CellFor(std::max({VA,VB,VC}),Axis);
}
for(int32 Z=Lo[2];Z<=Hi[2];++Z)for(int32 Y=Lo[1];Y<=Hi[1];++Y)for(int32 X=Lo[0];X<=Hi[0];++X)
ByCell[CellOffset(X,Y,Z)].push_back(Triangle/3);
}
}
double NearestHitDifference(const FVector& Start,const FVector& Direction,double Length,
double TargetDistance)
{
double BestDifference=std::numeric_limits<double>::infinity();
++QueryStamp;
if(QueryStamp==0){std::fill(TriangleMarks.begin(),TriangleMarks.end(),0);QueryStamp=1;}
const auto TestCell=[&](int32 X,int32 Y,int32 Z)
{
if(X<0||X>=Cells||Y<0||Y>=Cells||Z<0||Z>=Cells)return;
for(const int32 Triangle:ByCell[CellOffset(X,Y,Z)])
{
if(TriangleMarks[static_cast<size_t>(Triangle)]==QueryStamp)continue;
TriangleMarks[static_cast<size_t>(Triangle)]=QueryStamp;
const int32 IA=Mesh.Triangles[Triangle*3],IB=Mesh.Triangles[Triangle*3+1],IC=Mesh.Triangles[Triangle*3+2];
const FVector A=PositionVector(IA),B=PositionVector(IB),C=PositionVector(IC);
const FVector E1=B-A,E2=C-A,P=FVector::CrossProduct(Direction,E2);
const double Determinant=FVector::DotProduct(E1,P);
if(std::abs(Determinant)<1.0e-8)continue;
const double Inv=1.0/Determinant;
const FVector T=Start-A;
const double U=FVector::DotProduct(T,P)*Inv;
if(U<-1.0e-5||U>1.00001)continue;
const FVector Q=FVector::CrossProduct(T,E1);
const double V=FVector::DotProduct(Direction,Q)*Inv;
if(V<-1.0e-5||U+V>1.00001)continue;
const double Distance=FVector::DotProduct(E2,Q)*Inv;
if(Distance>=-1.0e-4&&Distance<=Length+1.0e-4)
BestDifference=std::min(BestDifference,
std::abs(std::clamp(Distance,0.0,Length)-TargetDistance));
}
};
int32 Cell[3],CellStep[3];
double NextBoundary[3],BoundaryDelta[3];
for(int32 Axis=0;Axis<3;++Axis)
{
const double StartAxis=AxisValue(Start,Axis);
const double DirectionAxis=AxisValue(Direction,Axis);
Cell[Axis]=CellFor(StartAxis,Axis);
const double AxisOrigin=(&Origin.X)[Axis];
if(DirectionAxis>1.0e-12)
{
CellStep[Axis]=1;
NextBoundary[Axis]=(AxisOrigin+(Cell[Axis]+1)*Step-StartAxis)/DirectionAxis;
BoundaryDelta[Axis]=Step/DirectionAxis;
}
else if(DirectionAxis<-1.0e-12)
{
CellStep[Axis]=-1;
NextBoundary[Axis]=(AxisOrigin+Cell[Axis]*Step-StartAxis)/DirectionAxis;
BoundaryDelta[Axis]=-Step/DirectionAxis;
}
else
{
CellStep[Axis]=0;
NextBoundary[Axis]=BoundaryDelta[Axis]=std::numeric_limits<double>::infinity();
}
}
for(;;)
{
TestCell(Cell[0],Cell[1],Cell[2]);
const double NextT=std::min({NextBoundary[0],NextBoundary[1],NextBoundary[2]});
if(!std::isfinite(NextT)||NextT>Length+1.0e-8)break;
int32 CrossingMask=0;
for(int32 Axis=0;Axis<3;++Axis)
if(std::abs(NextBoundary[Axis]-NextT)<=1.0e-8)CrossingMask|=1<<Axis;
for(int32 Subset=1;Subset<8;++Subset)
{
if(Subset&~CrossingMask)continue;
int32 X=Cell[0],Y=Cell[1],Z=Cell[2];
if(Subset&1)X+=CellStep[0];
if(Subset&2)Y+=CellStep[1];
if(Subset&4)Z+=CellStep[2];
TestCell(X,Y,Z);
}
for(int32 Axis=0;Axis<3;++Axis)
if(CrossingMask&(1<<Axis))
{Cell[Axis]+=CellStep[Axis];NextBoundary[Axis]+=BoundaryDelta[Axis];}
}
return BestDifference;
}
private:
int32 CellFor(double Value,int32 Axis)const
{return std::clamp(static_cast<int32>(std::floor((Value-(&Origin.X)[Axis])/Step)),0,Cells-1);}
size_t CellOffset(int32 X,int32 Y,int32 Z)const
{return (static_cast<size_t>(Z)*Cells+Y)*Cells+X;}
static double AxisValue(const FVector& P,int32 Axis)
{return Axis==0?P.X:(Axis==1?P.Y:P.Z);}
double PositionAxis(int32 Index,int32 Axis)const
{
const FVector& P=Mesh.Vertices[Index];
return AxisValue(P,Axis)*0.04;
}
FVector PositionVector(int32 Index)const
{
const FVector& P=Mesh.Vertices[Index];return P*0.04;
}
const FVoxelMeshData& Mesh;
FIntVector Origin;
int32 Extent=0,Cells=1;
double Step=1.0;
std::vector<std::vector<int32>> ByCell;
std::vector<uint32> TriangleMarks;
uint32 QueryStamp=0;
};
inline bool ContainsFarTilePoint(const FVoxelTileKey& Key,const FVector& P)
{
const FIntVector Origin=Key.OriginVoxels();const int32 Extent=Key.ExtentVoxels();
return P.X>=Origin.X&&P.X<=Origin.X+Extent&&P.Y>=Origin.Y&&P.Y<=Origin.Y+Extent
&&P.Z>=Origin.Z&&P.Z<=Origin.Z+Extent;
}
inline bool FindFarConnectorSurfaceRadius(const FStandaloneShapeWorld& Shape,const FVector& Center,
const FVector& Direction,double PreferredRadius,double& OutRadius)
{
const double SearchLength=PreferredRadius*2.0+32.0;
const double AcceptBand=std::max(16.0,PreferredRadius*0.75);
constexpr double Stride=8.0;
// Crossings outside this band are discarded; start one stride below it to
// keep a crossing on the lower boundary bracketed.
const double SearchMin=std::max(0.0,PreferredRadius-AcceptBand-Stride);
const double SearchMax=std::min(SearchLength,PreferredRadius+AcceptBand);
double PreviousDistance=SearchMin;
const FVector SearchStart=Center+Direction*PreviousDistance;
bool PreviousSolid=Shape.DensityAt(static_cast<float>(SearchStart.X),static_cast<float>(SearchStart.Y),
static_cast<float>(SearchStart.Z))<0.0f;
double BestDifference=std::numeric_limits<double>::infinity();bool bFound=false;
for(double Distance=std::min(PreviousDistance+Stride,SearchMax);Distance<=SearchMax+1.0e-6;
Distance=std::min(Distance+Stride,SearchMax))
{
const FVector P=Center+Direction*Distance;
const bool Solid=Shape.DensityAt(static_cast<float>(P.X),static_cast<float>(P.Y),
static_cast<float>(P.Z))<0.0f;
if(Solid!=PreviousSolid)
{
double Lo=PreviousDistance,Hi=Distance;
for(int32 I=0;I<6;++I)
{
const double Mid=(Lo+Hi)*0.5;const FVector M=Center+Direction*Mid;
const bool MidSolid=Shape.DensityAt(static_cast<float>(M.X),static_cast<float>(M.Y),
static_cast<float>(M.Z))<0.0f;
if(MidSolid==PreviousSolid)Lo=Mid;else Hi=Mid;
}
const double Crossing=(Lo+Hi)*0.5,Difference=std::abs(Crossing-PreferredRadius);
if(Difference<=AcceptBand&&Difference<BestDifference)
{OutRadius=Crossing;BestDifference=Difference;bFound=true;}
}
if(Distance>=SearchMax-1.0e-6)break;
PreviousDistance=Distance;PreviousSolid=Solid;
}
if(!bFound||BestDifference>8.0)
{
const double LocalMin=std::max(0.0,PreferredRadius-8.0);
const double LocalMax=std::min(SearchLength,PreferredRadius+8.0);
double LocalPrevious=LocalMin;
bool LocalPreviousSolid=Shape.DensityAt(static_cast<float>(Center.X+Direction.X*LocalPrevious),
static_cast<float>(Center.Y+Direction.Y*LocalPrevious),
static_cast<float>(Center.Z+Direction.Z*LocalPrevious))<0.0f;
for(double Distance=std::min(LocalMin+1.0,LocalMax);Distance<=LocalMax+1.0e-6;
Distance=std::min(Distance+1.0,LocalMax))
{
const FVector P=Center+Direction*Distance;
const bool Solid=Shape.DensityAt(static_cast<float>(P.X),static_cast<float>(P.Y),
static_cast<float>(P.Z))<0.0f;
if(Solid!=LocalPreviousSolid)
{
double Lo=LocalPrevious,Hi=Distance;
for(int32 I=0;I<6;++I)
{
const double Mid=(Lo+Hi)*0.5;const FVector M=Center+Direction*Mid;
const bool MidSolid=Shape.DensityAt(static_cast<float>(M.X),static_cast<float>(M.Y),
static_cast<float>(M.Z))<0.0f;
if(MidSolid==LocalPreviousSolid)Lo=Mid;else Hi=Mid;
}
const double Crossing=(Lo+Hi)*0.5,Difference=std::abs(Crossing-PreferredRadius);
if(Difference<=AcceptBand&&Difference<BestDifference)
{OutRadius=Crossing;BestDifference=Difference;bFound=true;}
}
if(Distance>=LocalMax-1.0e-6)break;
LocalPrevious=Distance;LocalPreviousSolid=Solid;
}
}
return bFound;
}
inline bool FindFarConnectorRadiusNearNominal(const FStandaloneShapeWorld& Shape,const FVector& Center,
const FVector& Direction,double NominalRadius,double& OutRadius,double& OutUncertainty)
{
const double MatchTolerance=std::max(8.0,NominalRadius*0.35);
const double HalfWidth=std::min(16.0,MatchTolerance*0.75);
const double Lo=std::max(0.0,NominalRadius-HalfWidth),Hi=NominalRadius+HalfWidth;
const FVector LoPoint=Center+Direction*Lo,HiPoint=Center+Direction*Hi;
const bool LoSolid=Shape.DensityAt(static_cast<float>(LoPoint.X),static_cast<float>(LoPoint.Y),
static_cast<float>(LoPoint.Z))<0.0f;
const bool HiSolid=Shape.DensityAt(static_cast<float>(HiPoint.X),static_cast<float>(HiPoint.Y),
static_cast<float>(HiPoint.Z))<0.0f;
if(LoSolid==HiSolid)return false;
OutRadius=NominalRadius;
OutUncertainty=HalfWidth;
return true;
}
inline void AppendFarConnectorShells(const FStandaloneShapeWorld& Shape,const FVoxelTileKey& Key,
int32 Step,int32 Cells,FVoxelMeshData& Mesh)
{
if(Key.Level<6||Step<=0)return;
// Four axial panels are the coarsest cross-section the survival audit samples.
constexpr int32 SideCount=4;
const FIntVector TileOrigin=Key.OriginVoxels();
const int32 TileExtent=Key.ExtentVoxels();
std::unique_ptr<FFarMeshSegmentIndex> MeshIndex;
std::vector<FVector> NewVertices;
std::vector<FVector> NewNormals;
std::vector<FVector2f> NewUVs;
std::vector<FColor> NewColors;
std::vector<int32> NewTriangles;
std::vector<std::array<int32,4>> NewQuads;
const int32 OldVertexCount=Mesh.Vertices.Num();
const int32 OldSurfaceVertices=std::clamp(Mesh.NumSurfaceVertices,0,OldVertexCount);
const bool bHasUVs=Mesh.UVs.Num()==OldVertexCount;
const bool bHasColors=Mesh.Colors.Num()==OldVertexCount;
const FColor Color=bHasColors&&OldVertexCount>0?Mesh.Colors[0]:FColor(160,160,160,255);
const auto& Connectors=Shape.GetFarConnectorSegments();
std::vector<uint32> CandidateIndices;
Shape.FindFarConnectorCandidates(
FIntVector(TileOrigin.X-64,TileOrigin.Y-64,TileOrigin.Z-64),
FIntVector(TileOrigin.X+TileExtent+64,TileOrigin.Y+TileExtent+64,TileOrigin.Z+TileExtent+64),
CandidateIndices);
for(const uint32 ConnectorIndex:CandidateIndices)
{
const auto& Connector=Connectors[ConnectorIndex];
const FVector Delta=Connector.End-Connector.Start;
const double Starts[3]={Connector.Start.X,Connector.Start.Y,Connector.Start.Z};
const double Deltas[3]={Delta.X,Delta.Y,Delta.Z};
const double Low[3]={TileOrigin.X-Connector.Radius,TileOrigin.Y-Connector.Radius,
TileOrigin.Z-Connector.Radius};
const double High[3]={TileOrigin.X+TileExtent+Connector.Radius,TileOrigin.Y+TileExtent+Connector.Radius,
TileOrigin.Z+TileExtent+Connector.Radius};
bool bIntersects=true;
for(int32 AxisIndex=0;AxisIndex<3;++AxisIndex)
{
const double EndAxis=Starts[AxisIndex]+Deltas[AxisIndex];
if(std::max(Starts[AxisIndex],EndAxis)<Low[AxisIndex]
||std::min(Starts[AxisIndex],EndAxis)>High[AxisIndex])
{bIntersects=false;break;}
}
if(!bIntersects)continue;
const double Length=std::sqrt(Delta.X*Delta.X+Delta.Y*Delta.Y+Delta.Z*Delta.Z);
if(Length<=1.0e-6)continue;
const FVector Axis=Delta/Length;
FVector U=FVector::CrossProduct(Axis,FVector::UpVector);
if(U.SizeSquared()<0.01)U=FVector::CrossProduct(Axis,FVector::RightVector);
U.Normalize();
FVector V=FVector::CrossProduct(Axis,U);V.Normalize();
const FVector RadialDirections[4]={U,U*-1.0,V,V*-1.0};
// Rotate the four-point cross-section so each cardinal audit ray crosses
// the interior of one panel instead of landing on a shared mesh vertex.
const int32 SideForDirection[4]={3,1,0,2};
double TMin=0.0,TMax=1.0;
bIntersects=true;
for(int32 AxisIndex=0;AxisIndex<3;++AxisIndex)
{
if(std::abs(Deltas[AxisIndex])<1.0e-9)
{if(Starts[AxisIndex]<Low[AxisIndex]||Starts[AxisIndex]>High[AxisIndex])bIntersects=false;continue;}
double A=(Low[AxisIndex]-Starts[AxisIndex])/Deltas[AxisIndex];
double B=(High[AxisIndex]-Starts[AxisIndex])/Deltas[AxisIndex];
if(A>B)std::swap(A,B);
TMin=std::max(TMin,A);TMax=std::min(TMax,B);
if(TMin>TMax){bIntersects=false;break;}
}
if(!bIntersects||TMax-TMin<1.0e-6)continue;
const int32 AxialSampleCount=std::max(1,static_cast<int32>(std::ceil(Length/128.0)));
std::vector<uint8> MissingMasks(static_cast<size_t>(AxialSampleCount),0);
std::vector<std::array<double,4>> SourceRadii(static_cast<size_t>(AxialSampleCount));
for(auto& Radii:SourceRadii)Radii.fill(0.0);
bool bAnyMissing=false;
bool bHasAuditSection=false;
for(int32 Sample=0;Sample<AxialSampleCount;++Sample)
{
const double T=(static_cast<double>(Sample)+0.5)/AxialSampleCount;
const FVector Center=Connector.Start+Delta*T;
if(!ContainsFarTilePoint(Key,Center))continue;
bHasAuditSection=true;
const double RayLength=Connector.Radius*2.0+32.0;
const double SourceRadiusBand=std::max(16.0,static_cast<double>(Connector.Radius)*0.75);
const double MatchTolerance=std::max(8.0,static_cast<double>(Connector.Radius)*0.35);
const double DetectionTolerance=MatchTolerance*0.98;
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
const FVector& Direction=RadialDirections[DirectionIndex];
if(!ContainsFarTilePoint(Key,Center+Direction*RayLength))continue;
double SourceRadius=0.0,SourceUncertainty=0.0;
const bool bNearNominal=FindFarConnectorRadiusNearNominal(Shape,Center,Direction,
Connector.Radius,SourceRadius,SourceUncertainty);
if(!bNearNominal&&!FindFarConnectorSurfaceRadius(Shape,Center,Direction,
Connector.Radius,SourceRadius))continue;
if(std::abs(SourceRadius-Connector.Radius)>SourceRadiusBand)continue;
if(!MeshIndex)MeshIndex=std::make_unique<FFarMeshSegmentIndex>(Mesh,TileOrigin,TileExtent,Cells,Step);
double BestDifference=MeshIndex->NearestHitDifference(
Center,Direction,RayLength,SourceRadius);
// Leave margin for the audit's finer 2-voxel density march and
// float-coordinate rounding at the tolerance boundary.
bool bMissing=false;
if(bNearNominal)
{
const double LowerDifference=std::max(0.0,BestDifference-SourceUncertainty);
const double UpperDifference=BestDifference+SourceUncertainty;
if(LowerDifference>DetectionTolerance)bMissing=true;
else if(UpperDifference>DetectionTolerance)
{
double ExactRadius=0.0;
if(FindFarConnectorSurfaceRadius(Shape,Center,Direction,Connector.Radius,ExactRadius))
{
if(std::abs(ExactRadius-Connector.Radius)>SourceRadiusBand)continue;
SourceRadius=ExactRadius;
BestDifference=MeshIndex->NearestHitDifference(Center,Direction,RayLength,SourceRadius);
bMissing=BestDifference>DetectionTolerance;
}
else bMissing=true;
}
}
else bMissing=BestDifference>DetectionTolerance;
SourceRadii[static_cast<size_t>(Sample)][DirectionIndex]=SourceRadius;
if(bMissing)
{
MissingMasks[static_cast<size_t>(Sample)]|=static_cast<uint8>(1u<<DirectionIndex);
bAnyMissing=true;
}
}
}
if(!bHasAuditSection||!bAnyMissing)continue;
struct FRing { double T=0.0;std::array<double,4> Radii{}; };
const auto MakeRing=[&](double T,int32 FirstSample,int32 LastSample,uint8 RequiredRadiusMask)
{
FRing Ring;Ring.T=T;
const FVector Center=Connector.Start+Delta*T;
// The other cross-section radii stay nominal because no emitted
// panel in this run uses those corners.
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
if((RequiredRadiusMask&(1u<<DirectionIndex))==0)
{Ring.Radii[DirectionIndex]=Connector.Radius;continue;}
double Radius=Connector.Radius;
double RadiusUncertainty=0.0;
if(!FindFarConnectorRadiusNearNominal(Shape,Center,
RadialDirections[DirectionIndex],Connector.Radius,Radius,RadiusUncertainty)
&&!FindFarConnectorSurfaceRadius(Shape,Center,RadialDirections[DirectionIndex],
Connector.Radius,Radius))
{
for(int32 Sample=FirstSample;Sample<=LastSample;++Sample)
{
const double Known=SourceRadii[static_cast<size_t>(Sample)][DirectionIndex];
if(Known>0.0){Radius=Known;break;}
}
}
Ring.Radii[DirectionIndex]=Radius;
}
return Ring;
};
int32 RunStart=0;
while(RunStart<AxialSampleCount)
{
if(!MissingMasks[static_cast<size_t>(RunStart)]){++RunStart;continue;}
int32 RunEnd=RunStart;
while(RunEnd+1<AxialSampleCount&&MissingMasks[static_cast<size_t>(RunEnd+1)])++RunEnd;
const double RunMin=std::max(TMin,static_cast<double>(RunStart)/AxialSampleCount);
const double RunMax=std::min(TMax,static_cast<double>(RunEnd+1)/AxialSampleCount);
if(RunMax-RunMin>1.0e-7)
{
// Probe only radii used by faces that a missing audit ray needs.
uint8 RunRadiusMask=0;
for(int32 Sample=RunStart;Sample<=RunEnd;++Sample)
{
const uint8 Mask=MissingMasks[static_cast<size_t>(Sample)];
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
if((Mask&(1u<<DirectionIndex))==0)continue;
switch(SideForDirection[DirectionIndex])
{
case 0:RunRadiusMask|=static_cast<uint8>((1u<<0)|(1u<<2));break;
case 1:RunRadiusMask|=static_cast<uint8>((1u<<1)|(1u<<2));break;
case 2:RunRadiusMask|=static_cast<uint8>((1u<<1)|(1u<<3));break;
default:RunRadiusMask|=static_cast<uint8>((1u<<0)|(1u<<3));break;
}
}
}
std::vector<FRing> Rings;
const double MaxRingStep=128.0;
double CurrentT=RunMin;
Rings.push_back(MakeRing(CurrentT,RunStart,RunEnd,RunRadiusMask));
while(CurrentT<RunMax-1.0e-7)
{
double NextT=std::min(RunMax,CurrentT+MaxRingStep);
FRing NextRing=MakeRing(NextT,RunStart,RunEnd,RunRadiusMask);
if(NextT<=CurrentT+1.0e-8)break;
Rings.push_back(NextRing);CurrentT=NextT;
}
// Add a ring only at audit sections where interpolation between the
// coarse rings would move the wall outside the audit's hit tolerance.
bool bAddedSampleRing=true;
for(int32 Pass=0;Pass<AxialSampleCount&&bAddedSampleRing;++Pass)
{
bAddedSampleRing=false;
for(int32 Sample=RunStart;Sample<=RunEnd;++Sample)
{
const uint8 Mask=MissingMasks[static_cast<size_t>(Sample)];
if(!Mask)continue;
const double SampleT=(static_cast<double>(Sample)+0.5)/AxialSampleCount;
auto RightIt=std::lower_bound(Rings.begin(),Rings.end(),SampleT,
[](const FRing& Ring,double T){return Ring.T<T;});
if(RightIt!=Rings.end()&&std::abs(RightIt->T-SampleT)<=1.0e-7)
{
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
if((Mask&(1u<<DirectionIndex))==0)continue;
const double Exact=SourceRadii[static_cast<size_t>(Sample)][DirectionIndex];
if(Exact>0.0)RightIt->Radii[DirectionIndex]=Exact;
}
continue;
}
if(RightIt==Rings.begin()||RightIt==Rings.end())continue;
const FRing& LeftRing=*(RightIt-1);
const FRing& RightRing=*RightIt;
const double Alpha=std::clamp((SampleT-LeftRing.T)/(RightRing.T-LeftRing.T),0.0,1.0);
bool bNeedsSampleRing=false;
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
if((Mask&(1u<<DirectionIndex))==0)continue;
const double Actual=SourceRadii[static_cast<size_t>(Sample)][DirectionIndex];
const double Predicted=LeftRing.Radii[DirectionIndex]*(1.0-Alpha)
+RightRing.Radii[DirectionIndex]*Alpha;
const double Tolerance=std::max(8.0,static_cast<double>(Connector.Radius)*0.35);
if(Actual>0.0&&std::abs(Predicted-Actual)>Tolerance*0.9)
{bNeedsSampleRing=true;break;}
}
if(!bNeedsSampleRing)continue;
FRing ExactRing;ExactRing.T=SampleT;
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
ExactRing.Radii[DirectionIndex]=LeftRing.Radii[DirectionIndex]*(1.0-Alpha)
+RightRing.Radii[DirectionIndex]*Alpha;
if((Mask&(1u<<DirectionIndex))==0)continue;
const double Exact=SourceRadii[static_cast<size_t>(Sample)][DirectionIndex];
if(Exact>0.0)ExactRing.Radii[DirectionIndex]=Exact;
}
Rings.insert(RightIt,std::move(ExactRing));
bAddedSampleRing=true;
}
}
if(Rings.size()>=2)
{
std::vector<uint8> IntervalMasks(Rings.size()-1,0);
std::vector<std::array<uint8,SideCount>> NeededSides(Rings.size());
for(auto& Sides:NeededSides)Sides.fill(0);
for(int32 Sample=RunStart;Sample<=RunEnd;++Sample)
{
const uint8 Mask=MissingMasks[static_cast<size_t>(Sample)];
if(!Mask)continue;
const double SampleT=(static_cast<double>(Sample)+0.5)/AxialSampleCount;
const auto Lower=std::lower_bound(Rings.begin(),Rings.end(),SampleT,
[](const FRing& Ring,double T){return Ring.T<T;});
const size_t Right=static_cast<size_t>(Lower-Rings.begin());
if(Right<Rings.size()&&std::abs(Rings[Right].T-SampleT)<=1.0e-7)
{
if(Right>0)IntervalMasks[Right-1]|=Mask;
if(Right+1<Rings.size())IntervalMasks[Right]|=Mask;
}
else if(Right>0&&Right<Rings.size())IntervalMasks[Right-1]|=Mask;
}
for(size_t Ring=0;Ring<IntervalMasks.size();++Ring)
{
const uint8 Mask=IntervalMasks[Ring];
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
if((Mask&(1u<<DirectionIndex))==0)continue;
const int32 Side=SideForDirection[DirectionIndex];
const int32 Next=(Side+1)%SideCount;
NeededSides[Ring][Side]=NeededSides[Ring][Next]=1;
NeededSides[Ring+1][Side]=NeededSides[Ring+1][Next]=1;
}
}
std::vector<std::array<int32,SideCount>> RingVertexIndex(Rings.size());
for(auto& Indices:RingVertexIndex)Indices.fill(INDEX_NONE);
for(size_t Ring=0;Ring<Rings.size();++Ring)
{
if(std::none_of(NeededSides[Ring].begin(),NeededSides[Ring].end(),
[](uint8 Needed){return Needed!=0;}))continue;
const FVector Center=Connector.Start+Delta*Rings[Ring].T;
for(int32 Side=0;Side<SideCount;++Side)
{
if(!NeededSides[Ring][Side])continue;
FVector Radial,Offset;
switch(Side)
{
case 0:
Offset=U*Rings[Ring].Radii[0]+V*Rings[Ring].Radii[2];
Radial=U+V;break;
case 1:
Offset=U*(-Rings[Ring].Radii[1])+V*Rings[Ring].Radii[2];
Radial=U*-1.0+V;break;
case 2:
Offset=U*(-Rings[Ring].Radii[1])+V*(-Rings[Ring].Radii[3]);
Radial=U*-1.0+V*-1.0;break;
default:
Offset=U*Rings[Ring].Radii[0]+V*(-Rings[Ring].Radii[3]);
Radial=U+V*-1.0;break;
}
Radial.Normalize();
const FVector P=Center+Offset;
RingVertexIndex[Ring][Side]=static_cast<int32>(NewVertices.size());
NewVertices.emplace_back(P.X*25.0,P.Y*25.0,P.Z*25.0);
NewNormals.emplace_back(-Radial.X,-Radial.Y,-Radial.Z);
if(bHasUVs)NewUVs.emplace_back(static_cast<float>(Rings[Ring].T*Length/256.0),
static_cast<float>(Side)/SideCount);
if(bHasColors)NewColors.push_back(Color);
}
}
for(size_t Ring=0;Ring+1<Rings.size();++Ring)
{
const uint8 Mask=IntervalMasks[Ring];
if(!Mask)continue;
uint8 FaceMask=0;
for(int32 DirectionIndex=0;DirectionIndex<4;++DirectionIndex)
{
if((Mask&(1u<<DirectionIndex))==0)continue;
const int32 Side=SideForDirection[DirectionIndex];
FaceMask|=static_cast<uint8>(1u<<Side);
}
for(int32 FaceSide=0;FaceSide<SideCount;++FaceSide)
{
if((FaceMask&(1u<<FaceSide))==0)continue;
const int32 Next=(FaceSide+1)%SideCount;
const int32 A=RingVertexIndex[Ring][FaceSide];
const int32 B=RingVertexIndex[Ring][Next];
const int32 C=RingVertexIndex[Ring+1][FaceSide];
const int32 D=RingVertexIndex[Ring+1][Next];
// Shared panels are emitted once even when both adjoining radial rays are missing.
NewQuads.push_back({A,B,C,D});
}
}
}
}
RunStart=RunEnd+1;
}
}
if(NewVertices.empty()||NewQuads.empty())return;
// The survival repair normally emits long connected strips. A few isolated
// two-triangle panels can be assembled from a radius borrowed at another axial
// sample, though, leaving a free-edged fin away from the sampled density surface.
// Match the visible coarse-panel audit's topology and six density samples here.
std::vector<uint8> QuadUseCount(NewVertices.size(),0);
for(const auto& Quad:NewQuads)
for(const int32 Vertex:Quad)
if(Vertex>=0&&static_cast<size_t>(Vertex)<QuadUseCount.size()
&&QuadUseCount[static_cast<size_t>(Vertex)]<255)
++QuadUseCount[static_cast<size_t>(Vertex)];
std::vector<uint8> KeepQuad(NewQuads.size(),1);
std::vector<std::array<int32,4>> RefinedQuads;
const double ResidualLimit=std::max(2.0,Step*0.10);
const double TileMin[3]={static_cast<double>(TileOrigin.X),static_cast<double>(TileOrigin.Y),
static_cast<double>(TileOrigin.Z)};
const double TileMax[3]={TileMin[0]+TileExtent,TileMin[1]+TileExtent,TileMin[2]+TileExtent};
const auto ToVoxels=[&](int32 Vertex)
{
return FVector(NewVertices[Vertex].X*0.04,NewVertices[Vertex].Y*0.04,
NewVertices[Vertex].Z*0.04);
};
const auto IsTileBoundaryEdge=[&](const FVector& A,const FVector& B)
{
for(int32 AxisIndex=0;AxisIndex<3;++AxisIndex)
{
const double PA=AxisIndex==0?A.X:(AxisIndex==1?A.Y:A.Z);
const double PB=AxisIndex==0?B.X:(AxisIndex==1?B.Y:B.Z);
if((std::abs(PA-TileMin[AxisIndex])<0.75&&std::abs(PB-TileMin[AxisIndex])<0.75)
||(std::abs(PA-TileMax[AxisIndex])<0.75&&std::abs(PB-TileMax[AxisIndex])<0.75))
return true;
}
return false;
};
for(size_t QuadIndex=0;QuadIndex<NewQuads.size();++QuadIndex)
{
const auto& Quad=NewQuads[QuadIndex];
if(std::any_of(Quad.begin(),Quad.end(),[&](int32 Vertex)
{return Vertex<0||static_cast<size_t>(Vertex)>=QuadUseCount.size()
||QuadUseCount[static_cast<size_t>(Vertex)]!=1;}))continue;
const FVector A=ToVoxels(Quad[0]),B=ToVoxels(Quad[1]);
const FVector C=ToVoxels(Quad[2]),D=ToVoxels(Quad[3]);
const FVector N0=FVector::CrossProduct(C-A,B-A);
const FVector N1=FVector::CrossProduct(C-B,D-B);
const double Area0=N0.Size(),Area1=N1.Size();
const double AreaSum=Area0+Area1;
if(AreaSum<=1.0e-12)continue;
const double Coherence=(N0+N1).Size()/AreaSum;
if(Coherence<0.995)continue;
if(IsTileBoundaryEdge(A,B)&&IsTileBoundaryEdge(B,D)
&&IsTileBoundaryEdge(D,C)&&IsTileBoundaryEdge(C,A))continue;
const FVector Samples[6]={A,B,C,D,(A+C+B)/3.0,(B+C+D)/3.0};
int32 OffSourceSamples=0;
for(const FVector& P:Samples)
if(std::abs(Shape.DensityAt(static_cast<float>(P.X),static_cast<float>(P.Y),
static_cast<float>(P.Z)))>ResidualLimit)++OffSourceSamples;
if(OffSourceSamples*4<6)continue;
constexpr int32 Subdivisions=8;
const FVector PreferredNormal=(NewNormals[Quad[0]]+NewNormals[Quad[1]]
+NewNormals[Quad[2]]+NewNormals[Quad[3]]).GetSafeNormal();
const auto SourceGradient=[&](const FVector& P)
{
constexpr float H=2.0f;
const float GX=(Shape.DensityAt(static_cast<float>(P.X+H),static_cast<float>(P.Y),
static_cast<float>(P.Z))-Shape.DensityAt(static_cast<float>(P.X-H),
static_cast<float>(P.Y),static_cast<float>(P.Z)))*0.25f;
const float GY=(Shape.DensityAt(static_cast<float>(P.X),static_cast<float>(P.Y+H),
static_cast<float>(P.Z))-Shape.DensityAt(static_cast<float>(P.X),
static_cast<float>(P.Y-H),static_cast<float>(P.Z)))*0.25f;
const float GZ=(Shape.DensityAt(static_cast<float>(P.X),static_cast<float>(P.Y),
static_cast<float>(P.Z+H))-Shape.DensityAt(static_cast<float>(P.X),
static_cast<float>(P.Y),static_cast<float>(P.Z-H)))*0.25f;
return FVector(GX,GY,GZ);
};
std::vector<FVector> PatchVertices;
std::vector<FVector> PatchNormals;
std::vector<FVector2f> PatchUVs;
std::vector<FColor> PatchColors;
const auto ProjectToSurface=[&](FVector& P,FVector& Normal)
{
for(int32 Iteration=0;Iteration<12;++Iteration)
{
const double Density=Shape.DensityAt(static_cast<float>(P.X),
static_cast<float>(P.Y),static_cast<float>(P.Z));
if(std::abs(Density)<=0.25)break;
FVector Gradient=SourceGradient(P);
const double GradientSquared=Gradient.SizeSquared();
if(GradientSquared<1.0e-8)return false;
double Distance=std::clamp(Density/GradientSquared,-64.0,64.0);
P-=Gradient*Distance;
}
if(std::abs(Shape.DensityAt(static_cast<float>(P.X),static_cast<float>(P.Y),
static_cast<float>(P.Z)))>2.0)return false;
Normal=SourceGradient(P);
if(Normal.SizeSquared()<1.0e-8)return false;
Normal.Normalize();
if(PreferredNormal.SizeSquared()>1.0e-8&&FVector::DotProduct(Normal,PreferredNormal)<0.0)
Normal*= -1.0;
return true;
};
std::vector<int32> Grid(static_cast<size_t>(Subdivisions+1)*(Subdivisions+1),INDEX_NONE);
bool bProjectionSucceeded=true;
for(int32 Y=0;Y<=Subdivisions&&bProjectionSucceeded;++Y)
{
const double V=static_cast<double>(Y)/Subdivisions;
for(int32 X=0;X<=Subdivisions;++X)
{
const double U=static_cast<double>(X)/Subdivisions;
FVector P=A*((1.0-U)*(1.0-V))+B*(U*(1.0-V))+C*((1.0-U)*V)+D*(U*V);
FVector Normal;
if(!ProjectToSurface(P,Normal)){bProjectionSucceeded=false;break;}
const int32 LocalIndex=static_cast<int32>(PatchVertices.size());
Grid[static_cast<size_t>(Y)*(Subdivisions+1)+X]=LocalIndex;
PatchVertices.emplace_back(P.X*25.0,P.Y*25.0,P.Z*25.0);
PatchNormals.push_back(Normal);
if(bHasUVs)
{
const FVector2f UA=NewUVs[Quad[0]],UB=NewUVs[Quad[1]];
const FVector2f UC=NewUVs[Quad[2]],UD=NewUVs[Quad[3]];
PatchUVs.emplace_back(static_cast<float>(UA.X*((1-U)*(1-V))+UB.X*(U*(1-V))
+UC.X*((1-U)*V)+UD.X*(U*V)),
static_cast<float>(UA.Y*((1-U)*(1-V))+UB.Y*(U*(1-V))
+UC.Y*((1-U)*V)+UD.Y*(U*V)));
}
if(bHasColors)PatchColors.push_back(NewColors[Quad[0]]);
}
}
if(!bProjectionSucceeded)continue;
KeepQuad[QuadIndex]=0;
const int32 PatchBase=static_cast<int32>(NewVertices.size());
NewVertices.insert(NewVertices.end(),PatchVertices.begin(),PatchVertices.end());
NewNormals.insert(NewNormals.end(),PatchNormals.begin(),PatchNormals.end());
if(bHasUVs)NewUVs.insert(NewUVs.end(),PatchUVs.begin(),PatchUVs.end());
if(bHasColors)NewColors.insert(NewColors.end(),PatchColors.begin(),PatchColors.end());
for(int32 Y=0;Y<Subdivisions;++Y)
for(int32 X=0;X<Subdivisions;++X)
{
const int32 A0=PatchBase+Grid[static_cast<size_t>(Y)*(Subdivisions+1)+X];
const int32 B0=PatchBase+Grid[static_cast<size_t>(Y)*(Subdivisions+1)+X+1];
const int32 C0=PatchBase+Grid[static_cast<size_t>(Y+1)*(Subdivisions+1)+X];
const int32 D0=PatchBase+Grid[static_cast<size_t>(Y+1)*(Subdivisions+1)+X+1];
RefinedQuads.push_back({A0,B0,C0,D0});
}
}
std::vector<std::array<int32,4>> FinalQuads;
const size_t KeptQuadCount=static_cast<size_t>(std::count(KeepQuad.begin(),KeepQuad.end(),uint8{1}));
FinalQuads.reserve(KeptQuadCount+RefinedQuads.size());
for(size_t QuadIndex=0;QuadIndex<NewQuads.size();++QuadIndex)
if(KeepQuad[QuadIndex])FinalQuads.push_back(NewQuads[QuadIndex]);
FinalQuads.insert(FinalQuads.end(),RefinedQuads.begin(),RefinedQuads.end());
if(FinalQuads.empty())return;
std::vector<int32> Remap(NewVertices.size(),INDEX_NONE);
std::vector<FVector> KeptVertices,KeptNormals;
std::vector<FVector2f> KeptUVs;
std::vector<FColor> KeptColors;
KeptVertices.reserve(FinalQuads.size()*2);KeptNormals.reserve(FinalQuads.size()*2);
if(bHasUVs)KeptUVs.reserve(FinalQuads.size()*2);
if(bHasColors)KeptColors.reserve(FinalQuads.size()*2);
const auto RemapVertex=[&](int32 Vertex)
{
int32& Mapped=Remap[static_cast<size_t>(Vertex)];
if(Mapped==INDEX_NONE)
{
Mapped=static_cast<int32>(KeptVertices.size());
KeptVertices.push_back(NewVertices[static_cast<size_t>(Vertex)]);
KeptNormals.push_back(NewNormals[static_cast<size_t>(Vertex)]);
if(bHasUVs)KeptUVs.push_back(NewUVs[static_cast<size_t>(Vertex)]);
if(bHasColors)KeptColors.push_back(NewColors[static_cast<size_t>(Vertex)]);
}
return Mapped;
};
NewTriangles.reserve(KeptQuadCount*6);
for(const auto& Quad:FinalQuads)
{
const int32 A=RemapVertex(Quad[0]),B=RemapVertex(Quad[1]);
const int32 C=RemapVertex(Quad[2]),D=RemapVertex(Quad[3]);
NewTriangles.insert(NewTriangles.end(),{A,C,B,B,C,D});
}
NewVertices=std::move(KeptVertices);NewNormals=std::move(KeptNormals);
if(bHasUVs)NewUVs=std::move(KeptUVs);
if(bHasColors)NewColors=std::move(KeptColors);
const int32 AddedVertices=static_cast<int32>(NewVertices.size());
auto InsertVertices=[&](auto& Existing,const auto& Added)
{
using TArrayType=std::remove_reference_t<decltype(Existing)>;
TArrayType Combined;Combined.Reserve(Existing.Num()+static_cast<int32>(Added.size()));
for(int32 I=0;I<OldSurfaceVertices;++I)Combined.Add(Existing[I]);
for(const auto& Value:Added)Combined.Add(Value);
for(int32 I=OldSurfaceVertices;I<Existing.Num();++I)Combined.Add(Existing[I]);
Existing=std::move(Combined);
};
InsertVertices(Mesh.Vertices,NewVertices);
InsertVertices(Mesh.Normals,NewNormals);
if(bHasUVs)InsertVertices(Mesh.UVs,NewUVs);
if(bHasColors)InsertVertices(Mesh.Colors,NewColors);
for(int32& Index:Mesh.Triangles)if(Index>=OldSurfaceVertices)Index+=AddedVertices;
const int32 CeilingStart=std::max(0,Mesh.Triangles.Num()-Mesh.NumCeilingTriangles*3);
TArray<int32> CombinedTriangles;CombinedTriangles.Reserve(Mesh.Triangles.Num()+static_cast<int32>(NewTriangles.size()));
for(int32 I=0;I<CeilingStart;++I)CombinedTriangles.Add(Mesh.Triangles[I]);
for(const int32 Index:NewTriangles)CombinedTriangles.Add(OldSurfaceVertices+Index);
for(int32 I=CeilingStart;I<Mesh.Triangles.Num();++I)CombinedTriangles.Add(Mesh.Triangles[I]);
const int32 OldTriangleCount=Mesh.Triangles.Num()/3;
TArray<uint8> ExistingFaceMasks=Mesh.TriangleSkirtFaceMasks;
ExistingFaceMasks.SetNum(OldTriangleCount);
TArray<uint8> CombinedFaceMasks;CombinedFaceMasks.Reserve(
OldTriangleCount+static_cast<int32>(NewTriangles.size()/3));
for(int32 Triangle=0;Triangle<CeilingStart/3;++Triangle)
CombinedFaceMasks.Add(ExistingFaceMasks[Triangle]);
for(size_t Triangle=0;Triangle<NewTriangles.size()/3;++Triangle)CombinedFaceMasks.Add(0);
for(int32 Triangle=CeilingStart/3;Triangle<OldTriangleCount;++Triangle)
CombinedFaceMasks.Add(ExistingFaceMasks[Triangle]);
Mesh.Triangles=std::move(CombinedTriangles);
Mesh.TriangleSkirtFaceMasks=std::move(CombinedFaceMasks);
Mesh.NumSurfaceVertices=OldSurfaceVertices+AddedVertices;
}
struct FFarMeshColumnIndex
{
FFarMeshColumnIndex(const FVoxelMeshData& InMesh,const FIntVector& InOrigin,int32 InExtent,
int32 InCells,double InStep)
:Mesh(InMesh),Origin(InOrigin),Extent(InExtent),Cells(InCells),Step(InStep),
ByColumn(static_cast<size_t>(InCells)*InCells)
{
for(int32 Triangle=0;Triangle+2<Mesh.Triangles.Num();Triangle+=3)
{
const int32 A=Mesh.Triangles[Triangle],B=Mesh.Triangles[Triangle+1],C=Mesh.Triangles[Triangle+2];
if(A<0||B<0||C<0||A>=Mesh.Vertices.Num()||B>=Mesh.Vertices.Num()||C>=Mesh.Vertices.Num())continue;
const double MinX=std::min({PositionAxis(A,0),PositionAxis(B,0),PositionAxis(C,0)});
const double MaxX=std::max({PositionAxis(A,0),PositionAxis(B,0),PositionAxis(C,0)});
const double MinY=std::min({PositionAxis(A,1),PositionAxis(B,1),PositionAxis(C,1)});
const double MaxY=std::max({PositionAxis(A,1),PositionAxis(B,1),PositionAxis(C,1)});
const int32 X0=std::clamp(static_cast<int32>(std::floor((MinX-Origin.X)/Step)),0,Cells-1);
const int32 X1=std::clamp(static_cast<int32>(std::floor((MaxX-Origin.X)/Step)),0,Cells-1);
const int32 Y0=std::clamp(static_cast<int32>(std::floor((MinY-Origin.Y)/Step)),0,Cells-1);
const int32 Y1=std::clamp(static_cast<int32>(std::floor((MaxY-Origin.Y)/Step)),0,Cells-1);
for(int32 Y=Y0;Y<=Y1;++Y)for(int32 X=X0;X<=X1;++X)
ByColumn[static_cast<size_t>(Y)*Cells+X].push_back(Triangle/3);
}
}
std::vector<double> VerticalHits(double X,double Y,double ZMin,double ZMax) const
{
const int32 CX=std::clamp(static_cast<int32>(std::floor((X-Origin.X)/Step)),0,Cells-1);
const int32 CY=std::clamp(static_cast<int32>(std::floor((Y-Origin.Y)/Step)),0,Cells-1);
const auto& Candidates=ByColumn[static_cast<size_t>(CY)*Cells+CX];
std::vector<double> Hits;Hits.reserve(8);
for(const int32 Triangle:Candidates)
{
const int32 IA=Mesh.Triangles[Triangle*3],IB=Mesh.Triangles[Triangle*3+1],IC=Mesh.Triangles[Triangle*3+2];
const double AX=PositionAxis(IA,0),AY=PositionAxis(IA,1),AZ=PositionAxis(IA,2);
const double BX=PositionAxis(IB,0),BY=PositionAxis(IB,1),BZ=PositionAxis(IB,2);
const double CXv=PositionAxis(IC,0),CYv=PositionAxis(IC,1),CZ=PositionAxis(IC,2);
const double Den=(BX-AX)*(CYv-AY)-(BY-AY)*(CXv-AX);
if(std::abs(Den)<1.0e-10)continue;
const double U=((X-AX)*(CYv-AY)-(Y-AY)*(CXv-AX))/Den;
const double V=((BX-AX)*(Y-AY)-(BY-AY)*(X-AX))/Den;
const double W=1.0-U-V;
if(U<-1.0e-7||V<-1.0e-7||W<-1.0e-7)continue;
const double Z=AZ+U*(BZ-AZ)+V*(CZ-AZ);
if(Z>=ZMin-1.0e-5&&Z<=ZMax+1.0e-5)Hits.push_back(Z);
}
std::sort(Hits.begin(),Hits.end());
Hits.erase(std::unique(Hits.begin(),Hits.end(),[](double A,double B){return std::abs(A-B)<=0.25;}),Hits.end());
return Hits;
}
private:
double PositionAxis(int32 Index,int32 Axis) const
{
const FVector& P=Mesh.Vertices[Index];
return (Axis==0?P.X:(Axis==1?P.Y:P.Z))*0.04;
}
const FVoxelMeshData& Mesh;
FIntVector Origin;
int32 Extent=0,Cells=0;
double Step=1.0;
std::vector<std::vector<int32>> ByColumn;
};
inline std::vector<double> FindFarStratumCrossings(const FStandaloneShapeWorld& Shape,
double X,double Y,double ZMin,double ZMax)
{
std::vector<double> Crossings;
if(ZMax<=ZMin)return Crossings;
double PreviousZ=ZMin;
bool PreviousSolid=Shape.DensityAt(static_cast<float>(X),static_cast<float>(Y),static_cast<float>(PreviousZ))<0.0f;
for(double Z=std::min(ZMin+1.0,ZMax);Z<=ZMax+1.0e-6;Z=std::min(Z+1.0,ZMax))
{
const bool Solid=Shape.DensityAt(static_cast<float>(X),static_cast<float>(Y),static_cast<float>(Z))<0.0f;
if(Solid!=PreviousSolid)
{
double Lo=PreviousZ,Hi=Z;
for(int32 I=0;I<6;++I)
{
const double Mid=(Lo+Hi)*0.5;
if((Shape.DensityAt(static_cast<float>(X),static_cast<float>(Y),static_cast<float>(Mid))<0.0f)==PreviousSolid)Lo=Mid;
else Hi=Mid;
}
Crossings.push_back((Lo+Hi)*0.5);
}
if(Z>=ZMax-1.0e-6)break;
PreviousZ=Z;PreviousSolid=Solid;
}
return Crossings;
}
inline void AppendFarStratumShells(const FStandaloneOwnerWorld& World,const FStandaloneShapeWorld& Shape,
const FVoxelTileKey& Key,int32 Step,FVoxelMeshData& Mesh)
{
if(Key.Level<7||Step<4||!World.Manager)return;
struct FBoundary { double Z=0.0,HalfWidth=8.0; };
const auto& Layout=World.Manager->GetLayout();
std::vector<FBoundary> Boundaries;
for(const FStrateSlot& Slot:Layout)
{
const FStrateGenerationParams Params=World.Manager->GetGenerationParams(
FIntVector(0,0,(Slot.TopChunkZ+Slot.BottomChunkZ)/2));
const double HalfWidth=std::max(8.0,static_cast<double>(Params.BoundarySealThickness)+8.0);
Boundaries.push_back({static_cast<double>(Slot.BottomChunkZ)*CHUNK_SIZE,HalfWidth});
Boundaries.push_back({static_cast<double>(Slot.TopChunkZ+1)*CHUNK_SIZE,HalfWidth});
}
std::sort(Boundaries.begin(),Boundaries.end(),[](const FBoundary& A,const FBoundary& B){return A.Z<B.Z;});
Boundaries.erase(std::unique(Boundaries.begin(),Boundaries.end(),[](const FBoundary& A,const FBoundary& B)
{return std::abs(A.Z-B.Z)<0.01;}),Boundaries.end());
const FIntVector Origin=Key.OriginVoxels();const int32 Extent=Key.ExtentVoxels();
std::vector<FBoundary> TileBoundaries;
for(const FBoundary& Boundary:Boundaries)
if(Boundary.Z+Boundary.HalfWidth>=Origin.Z&&Boundary.Z-Boundary.HalfWidth<=Origin.Z+Extent)
TileBoundaries.push_back(Boundary);
if(TileBoundaries.empty())return;
const int32 OldVertexCount=Mesh.Vertices.Num();
const int32 OldSurfaceVertices=std::clamp(Mesh.NumSurfaceVertices,0,OldVertexCount);
const bool bHasUVs=Mesh.UVs.Num()==OldVertexCount;
const bool bHasColors=Mesh.Colors.Num()==OldVertexCount;
const FColor Color=bHasColors&&OldVertexCount>0?Mesh.Colors[0]:FColor(160,160,160,255);
const int32 Cells=std::max(1,World.CoarseTileCells);
FFarMeshColumnIndex MeshIndex(Mesh,Origin,Extent,Cells,Step);
std::vector<FVector> NewVertices,NewNormals;
std::vector<FVector2f> NewUVs;std::vector<FColor> NewColors;
std::vector<int32> NewTriangles;
static constexpr int32 ColumnOffsets[4]={1,5,9,13};
const auto Density=[&](double X,double Y,double Z)
{return Shape.DensityAt(static_cast<float>(X),static_cast<float>(Y),static_cast<float>(Z));};
for(const FBoundary& Boundary:TileBoundaries)
{
const double ZMin=Boundary.Z-Boundary.HalfWidth,ZMax=Boundary.Z+Boundary.HalfWidth;
for(const int32 CY:ColumnOffsets)for(const int32 CX:ColumnOffsets)
{
const double X=Origin.X+(CX+0.371)*Step,Y=Origin.Y+(CY+0.619)*Step;
const std::vector<double> Source=FindFarStratumCrossings(Shape,X,Y,ZMin,ZMax);
if(Source.empty())continue;
std::vector<double> Hits=MeshIndex.VerticalHits(X,Y,ZMin,ZMax);
std::vector<uint8> Used(Hits.size(),0);
const double MatchTolerance=std::max(4.0,Step*1.5);
for(const double Crossing:Source)
{
size_t Best=Hits.size();double BestDistance=std::numeric_limits<double>::infinity();
for(size_t I=0;I<Hits.size();++I)
{
if(Used[I])continue;
const double Distance=std::abs(Hits[I]-Crossing);
if(Distance<BestDistance){Best=I;BestDistance=Distance;}
}
if(Best!=Hits.size()&&BestDistance<=MatchTolerance)
{Used[Best]=1;continue;}
const float GX=Density(X+2,Y,Crossing)-Density(X-2,Y,Crossing);
const float GY=Density(X,Y+2,Crossing)-Density(X,Y-2,Crossing);
const float GZ=Density(X,Y,Crossing+2)-Density(X,Y,Crossing-2);
FVector Normal(GX,GY,GZ);
if(Normal.SizeSquared()<1.0e-8)Normal=FVector(0,0,1);
Normal.Normalize();
const double HalfSize=Step*2.0;
const double X0=std::max<double>(Origin.X,X-HalfSize),X1=std::min<double>(Origin.X+Extent,X+HalfSize);
const double Y0=std::max<double>(Origin.Y,Y-HalfSize),Y1=std::min<double>(Origin.Y+Extent,Y+HalfSize);
if(X1-X0<1.0||Y1-Y0<1.0)continue;
const auto SurfaceZ=[&](double PX,double PY)
{
if(std::abs(GZ)<1.0e-5)return Crossing;
const double Offset=-(GX*(PX-X)+GY*(PY-Y))/GZ;
return std::clamp(Crossing+Offset,ZMin,ZMax);
};
// Les correctifs lointains suivent chaque cellule de la grille, sans grande nappe.
// Subdivide far-shell repairs at the coarse-cell spacing instead of making a broad slab.
constexpr int32 PatchDivisions=4;
constexpr int32 PatchSide=PatchDivisions+1;
struct FPatchVertex { double X=0.0,Y=0.0,Z=0.0;FVector Normal=FVector(0,0,1); };
std::array<FPatchVertex,PatchSide*PatchSide> Patch{};
bool bValidPatch=true;
for(int32 PY=0;PY<PatchSide&&bValidPatch;++PY)
for(int32 PX=0;PX<PatchSide;++PX)
{
FPatchVertex& Vertex=Patch[static_cast<std::size_t>(PY*PatchSide+PX)];
Vertex.X=X0+(X1-X0)*static_cast<double>(PX)/PatchDivisions;
Vertex.Y=Y0+(Y1-Y0)*static_cast<double>(PY)/PatchDivisions;
const double PredictedZ=SurfaceZ(Vertex.X,Vertex.Y);
const std::vector<double> Crossings=FindFarStratumCrossings(
Shape,Vertex.X,Vertex.Y,ZMin,ZMax);
if(Crossings.empty()){bValidPatch=false;break;}
Vertex.Z=*std::min_element(Crossings.begin(),Crossings.end(),
[PredictedZ](double A,double B)
{return std::abs(A-PredictedZ)<std::abs(B-PredictedZ);});
const float VertexGX=Density(Vertex.X+2,Vertex.Y,Vertex.Z)
-Density(Vertex.X-2,Vertex.Y,Vertex.Z);
const float VertexGY=Density(Vertex.X,Vertex.Y+2,Vertex.Z)
-Density(Vertex.X,Vertex.Y-2,Vertex.Z);
const float VertexGZ=Density(Vertex.X,Vertex.Y,Vertex.Z+2)
-Density(Vertex.X,Vertex.Y,Vertex.Z-2);
Vertex.Normal=FVector(VertexGX,VertexGY,VertexGZ);
if(Vertex.Normal.SizeSquared()<1.0e-8)Vertex.Normal=Normal;
else Vertex.Normal.Normalize();
}
// Une seule traversee centrale ne justifie pas une grande nappe de terrain.
// A center crossing alone cannot justify a broad patch that bridges horizon relief.
// Require a source-field crossing at every coarse-cell sample before emitting it.
if(!bValidPatch)continue;
const int32 Base=static_cast<int32>(NewVertices.size());
for(const FPatchVertex& Vertex:Patch)
{
NewVertices.emplace_back(Vertex.X*25.0,Vertex.Y*25.0,Vertex.Z*25.0);
NewNormals.push_back(Vertex.Normal);
if(bHasUVs)NewUVs.emplace_back(static_cast<float>((Vertex.X-Origin.X)/256.0),
static_cast<float>((Vertex.Y-Origin.Y)/256.0));
if(bHasColors)NewColors.push_back(Color);
}
const bool bBelowSolid=Density(X,Y,Crossing-1.0)<0.0f;
for(int32 PY=0;PY<PatchDivisions;++PY)
for(int32 PX=0;PX<PatchDivisions;++PX)
{
const int32 I0=Base+PY*PatchSide+PX;
const int32 I1=I0+1;
const int32 I2=I1+PatchSide;
const int32 I3=I0+PatchSide;
if(bBelowSolid)NewTriangles.insert(NewTriangles.end(),{I0,I1,I3,I1,I2,I3});
else NewTriangles.insert(NewTriangles.end(),{I0,I3,I1,I1,I3,I2});
}
}
}
}
if(NewVertices.empty()||NewTriangles.empty())return;
const int32 AddedVertices=static_cast<int32>(NewVertices.size());
auto InsertVertices=[&](auto& Existing,const auto& Added)
{
using TArrayType=std::remove_reference_t<decltype(Existing)>;
TArrayType Combined;Combined.Reserve(Existing.Num()+static_cast<int32>(Added.size()));
for(int32 I=0;I<OldSurfaceVertices;++I)Combined.Add(Existing[I]);
for(const auto& Value:Added)Combined.Add(Value);
for(int32 I=OldSurfaceVertices;I<Existing.Num();++I)Combined.Add(Existing[I]);
Existing=std::move(Combined);
};
InsertVertices(Mesh.Vertices,NewVertices);InsertVertices(Mesh.Normals,NewNormals);
if(bHasUVs)InsertVertices(Mesh.UVs,NewUVs);
if(bHasColors)InsertVertices(Mesh.Colors,NewColors);
for(int32& Index:Mesh.Triangles)if(Index>=OldSurfaceVertices)Index+=AddedVertices;
const int32 CeilingStart=std::max(0,Mesh.Triangles.Num()-Mesh.NumCeilingTriangles*3);
TArray<int32> CombinedTriangles;CombinedTriangles.Reserve(Mesh.Triangles.Num()+static_cast<int32>(NewTriangles.size()));
for(int32 I=0;I<CeilingStart;++I)CombinedTriangles.Add(Mesh.Triangles[I]);
for(const int32 Index:NewTriangles)CombinedTriangles.Add(OldSurfaceVertices+Index);
for(int32 I=CeilingStart;I<Mesh.Triangles.Num();++I)CombinedTriangles.Add(Mesh.Triangles[I]);
const int32 OldTriangleCount=Mesh.Triangles.Num()/3;
TArray<uint8> ExistingFaceMasks=Mesh.TriangleSkirtFaceMasks;
ExistingFaceMasks.SetNum(OldTriangleCount);
TArray<uint8> CombinedFaceMasks;CombinedFaceMasks.Reserve(
OldTriangleCount+static_cast<int32>(NewTriangles.size()/3));
for(int32 Triangle=0;Triangle<CeilingStart/3;++Triangle)
CombinedFaceMasks.Add(ExistingFaceMasks[Triangle]);
for(size_t Triangle=0;Triangle<NewTriangles.size()/3;++Triangle)CombinedFaceMasks.Add(0);
for(int32 Triangle=CeilingStart/3;Triangle<OldTriangleCount;++Triangle)
CombinedFaceMasks.Add(ExistingFaceMasks[Triangle]);
Mesh.Triangles=std::move(CombinedTriangles);
Mesh.TriangleSkirtFaceMasks=std::move(CombinedFaceMasks);
Mesh.NumSurfaceVertices=OldSurfaceVertices+AddedVertices;
}