float BaseMesh::SidedSurfaceArea(const Plane &P)
{
float Result = 0.0f;
DWORD *MyIndices = Indices();
MeshVertex *MyVertices = Vertices();
UINT TriangleCount = FaceCount();
for(UINT TriangleIndex = 0; TriangleIndex < TriangleCount; TriangleIndex++)
{
Vec3f LocalTriangle[6];
UINT TSide[3];
for(UINT LocalVertexIndex = 0; LocalVertexIndex < 3; LocalVertexIndex++)
{
LocalTriangle[LocalVertexIndex] = MyVertices[MyIndices[TriangleIndex * 3 + LocalVertexIndex]].Pos;
if(Plane::DotCoord(P, LocalTriangle[LocalVertexIndex]) < 0.0f)
{
TSide[LocalVertexIndex] = 0;
}
else
{
TSide[LocalVertexIndex] = 1;
}
}
UINT TriangleType = TSide[0] * 4 + TSide[1] * 2 + TSide[2] * 1;
for(UINT EdgeIndex = 0; EdgeIndex < 3; EdgeIndex++)
{
if(PerfectEdges[TriangleType][EdgeIndex])
{
Vec3f Vtx1 = MyVertices[MyIndices[TriangleIndex * 3 + PerfectEdgeList[EdgeIndex][0]]].Pos;
Vec3f Vtx2 = MyVertices[MyIndices[TriangleIndex * 3 + PerfectEdgeList[EdgeIndex][1]]].Pos;
Vec3f VtxIntersect = P.IntersectLine(Vtx1, Vtx2);
if(!Vec3f::WithinRect(VtxIntersect, Rectangle3f::ConstructFromTwoPoints(Vtx1, Vtx2)))
{
VtxIntersect = (Vtx1 + Vtx2) * 0.5f;
}
LocalTriangle[3 + EdgeIndex] = VtxIntersect;
}
}
for(UINT LocalTriangleIndex = 0; LocalTriangleIndex < 6; LocalTriangleIndex += 3)
{
if(M1Indices[TriangleType][LocalTriangleIndex] != -1)
{
Vec3f V[3];
V[0] = LocalTriangle[M1Indices[TriangleType][LocalTriangleIndex + 0]];
V[1] = LocalTriangle[M1Indices[TriangleType][LocalTriangleIndex + 1]];
V[2] = LocalTriangle[M1Indices[TriangleType][LocalTriangleIndex + 2]];
Result += Math::TriangleArea(V[0], V[1], V[2]);
}
}
}
return Result;
}
void BaseMesh::ClosedPlaneSplit(const Plane &P, BaseMesh &M1, BaseMesh &M2)
{
UINT VC = VertexCount(), IC = IndexCount();
MeshVertex *V = Vertices();
DWORD *I = Indices();
Vector<Vec3f> NewVertices[2];
Vector<TriMeshFace> NewFaces[2];
Vector<Vec2f> BoundaryVertices;
Vector<UINT> BoundaryIndices[2];
Vec3f OrthogonalBasis1, OrthogonalBasis2;
Vec3f::CompleteOrthonormalBasis(P.Normal(), OrthogonalBasis1, OrthogonalBasis2);
PerfectSplitVMapper *VMap = new PerfectSplitVMapper[VC];
for(UINT VertexIndex = 0; VertexIndex < VC; VertexIndex++)
{
Vec3f Pos = V[VertexIndex].Pos;
float Value = Plane::DotCoord(P, Pos);
if(Value < 0.0f)
{
VMap[VertexIndex].Side = 0;
VMap[VertexIndex].NVMap = NewVertices[0].Length();
NewVertices[0].PushEnd(Pos);
}
else
{
VMap[VertexIndex].Side = 1;
VMap[VertexIndex].NVMap = NewVertices[1].Length();
NewVertices[1].PushEnd(Pos);
}
}
for(UINT IndexIndex = 0; IndexIndex < IC; IndexIndex += 3)
{
int TSide[3];
TSide[0] = VMap[I[IndexIndex + 0]].Side;
TSide[1] = VMap[I[IndexIndex + 1]].Side;
TSide[2] = VMap[I[IndexIndex + 2]].Side;
DWORD LocalTriangleM1[6], LocalTriangleM2[6];
LocalTriangleM2[0] = LocalTriangleM1[0] = VMap[I[IndexIndex + 0]].NVMap;
LocalTriangleM2[1] = LocalTriangleM1[1] = VMap[I[IndexIndex + 1]].NVMap;
LocalTriangleM2[2] = LocalTriangleM1[2] = VMap[I[IndexIndex + 2]].NVMap;
UINT TriangleType = TSide[0] * 4 + TSide[1] * 2 + TSide[2] * 1;
for(UINT EdgeIndex = 0; EdgeIndex < 3; EdgeIndex++)
{
if(PerfectEdges[TriangleType][EdgeIndex])
{
Vec3f Vtx1 = V[I[IndexIndex + PerfectEdgeList[EdgeIndex][0]]].Pos;
Vec3f Vtx2 = V[I[IndexIndex + PerfectEdgeList[EdgeIndex][1]]].Pos;
Vec3f VtxIntersect = P.IntersectLine(Vtx1, Vtx2);
if(!Vec3f::WithinRect(VtxIntersect, Rectangle3f::ConstructFromTwoPoints(Vtx1, Vtx2)))
{
VtxIntersect = (Vtx1 + Vtx2) * 0.5f;
}
BoundaryVertices.PushEnd(Vec2f(Vec3f::Dot(VtxIntersect, OrthogonalBasis1), Vec3f::Dot(VtxIntersect, OrthogonalBasis2)));
LocalTriangleM1[3 + EdgeIndex] = NewVertices[0].Length();
BoundaryIndices[0].PushEnd(NewVertices[0].Length());
NewVertices[0].PushEnd(VtxIntersect);
LocalTriangleM2[3 + EdgeIndex] = NewVertices[1].Length();
BoundaryIndices[1].PushEnd(NewVertices[1].Length());
NewVertices[1].PushEnd(VtxIntersect);
}
}
for(UINT LocalTriangleIndex = 0; LocalTriangleIndex < 6; LocalTriangleIndex += 3)
{
if(M1Indices[TriangleType][LocalTriangleIndex] != -1)
{
TriMeshFace Tri;
Tri.I[0] = LocalTriangleM1[M1Indices[TriangleType][LocalTriangleIndex + 0]];
Tri.I[1] = LocalTriangleM1[M1Indices[TriangleType][LocalTriangleIndex + 1]];
Tri.I[2] = LocalTriangleM1[M1Indices[TriangleType][LocalTriangleIndex + 2]];
NewFaces[0].PushEnd(Tri);
}
if(M2Indices[TriangleType][LocalTriangleIndex] != -1)
{
TriMeshFace Tri;
Tri.I[0] = LocalTriangleM2[M2Indices[TriangleType][LocalTriangleIndex + 0]];
Tri.I[1] = LocalTriangleM2[M2Indices[TriangleType][LocalTriangleIndex + 1]];
Tri.I[2] = LocalTriangleM2[M2Indices[TriangleType][LocalTriangleIndex + 2]];
NewFaces[1].PushEnd(Tri);
}
}
}
#ifdef DELAUNAY_TRIANGULATOR
if(BoundaryVertices.Length() > 0)
{
Vector<DWORD> BoundaryTriangulation;
DelaunayTriangulator::Triangulate(BoundaryVertices, BoundaryTriangulation);
for(UINT TriangleIndex = 0; TriangleIndex < BoundaryTriangulation.Length() / 3; TriangleIndex++)
{
for(UINT MeshIndex = 0; MeshIndex < 2; MeshIndex++)
{
TriMeshFace Tri;
Vec3f V[3];
for(UINT LocalVertexIndex = 0; LocalVertexIndex < 3; LocalVertexIndex++)
{
Tri.I[LocalVertexIndex] = BoundaryIndices[MeshIndex][UINT(BoundaryTriangulation[TriangleIndex * 3 + LocalVertexIndex])];
V[LocalVertexIndex] = NewVertices[MeshIndex][UINT(Tri.I[LocalVertexIndex])];
}
//Utility::Swap(Tri.I[0], Tri.I[1]);
//if(Math::TriangleArea(V[0], V[1], V[2]) > 1e-5f)
{
NewFaces[MeshIndex].PushEnd(Tri);
}
}
}
}
#endif
delete[] VMap;
M1.SetGD(GetGD());
M2.SetGD(GetGD());
M1.Allocate(NewVertices[0].Length(), NewFaces[0].Length());
M2.Allocate(NewVertices[1].Length(), NewFaces[1].Length());
for(UINT VertexIndex = 0; VertexIndex < NewVertices[0].Length(); VertexIndex++)
{
M1.Vertices()[VertexIndex].Pos = NewVertices[0][VertexIndex];
}
for(UINT VertexIndex = 0; VertexIndex < NewVertices[1].Length(); VertexIndex++)
{
M2.Vertices()[VertexIndex].Pos = NewVertices[1][VertexIndex];
}
if(NewFaces[0].Length() > 0)
{
memcpy(M1.Indices(), NewFaces[0].CArray(), M1.IndexCount() * sizeof(DWORD));
}
if(NewFaces[1].Length() > 0)
{
memcpy(M2.Indices(), NewFaces[1].CArray(), M2.IndexCount() * sizeof(DWORD));
}
}