void Mesh::Clip(const Plane & plane,
SArray< Vec3<double> > & positivePart,
SArray< Vec3<double> > & negativePart) const
{
const size_t nV = GetNPoints();
if (nV == 0)
{
return;
}
double d;
for (size_t v = 0; v < nV; v++)
{
const Vec3<double> & pt = GetPoint(v);
d = plane.m_a * pt[0] + plane.m_b * pt[1] + plane.m_c * pt[2] + plane.m_d;
if (d > 0.0)
{
positivePart.PushBack(pt);
}
else if (d < 0.0)
{
negativePart.PushBack(pt);
}
else
{
positivePart.PushBack(pt);
negativePart.PushBack(pt);
}
}
}
bool PolyLine2::PtIn( const Vec2& pt ) const
{
int nP = GetNPoints();
if (nP < 3) return false;
int nW = 0;
// loop through all edges of the polygon
for (int i = 0; i < nP; i++)
{
const Vec2& a = m_Points[i];
const Vec2& b = GetPoint( i + 1 );
if (a.y <= pt.y)
{
if (b.y > pt.y)
{
if (pt.leftof( a, b ) > 0.0f)
{
nW++;
}
}
}
else
{
if (b.y <= pt.y)
{
if (pt.leftof( a, b ) < 0.0f)
{
nW--;
}
}
}
}
return (nW != 0);
}
double Mesh::ComputeVolume() const
{
const size_t nV = GetNPoints();
const size_t nT = GetNTriangles();
if (nV == 0 || nT == 0)
{
return 0.0;
}
Vec3<double> bary(0.0, 0.0, 0.0);
for (size_t v = 0; v < nV; v++)
{
bary += GetPoint(v);
}
bary /= static_cast<double>(nV);
Vec3<double> ver0, ver1, ver2;
double totalVolume = 0.0;
for(size_t t = 0; t < nT; t++)
{
const Vec3<int> & tri = GetTriangle(t);
ver0 = GetPoint(tri[0]);
ver1 = GetPoint(tri[1]);
ver2 = GetPoint(tri[2]);
totalVolume += ComputeVolume4(ver0, ver1, ver2, bary);
}
return totalVolume/6.0;
}
Vec2 PolyLine2::GetCenter() const
{
int nP = GetNPoints();
Vec2 res( 0.0f, 0.0f );
for (int i = 0; i < nP; i++)
{
res += GetPoint( i );
}
res /= float( nP );
return res;
}
bool PolyLine2::AddPoint( const Vec2& pt, bool bNoSelfCross )
{
int nP = GetNPoints();
if (bNoSelfCross && nP > 0)
{
int nSeg = GetNSegments() - 2;
Seg2 newSeg( pt, GetPoint( nP - 1 ) );
for (int i = 0; i < nSeg; i++)
{
if (newSeg.intersects( GetEdge( i ) )) return false;
}
}
m_Points.push_back( pt );
return true;
}
Frame PolyLine2::GetBound() const
{
int nP = GetNPoints();
if (nP == 0) return Frame::null;
const Vec2& p0 = GetPoint( 0 );
Frame rect( p0.x, p0.y, p0.x, p0.y );
for (int i = 1; i < nP; i++)
{
const Vec2& p = GetPoint( i );
if (p.x < rect.x) rect.x = p.x;
if (p.y < rect.y) rect.y = p.y;
if (p.x > rect.w) rect.w = p.x;
if (p.y > rect.h) rect.h = p.y;
}
rect.w -= rect.x;
rect.h -= rect.y;
return rect;
}
double Mesh::ComputeDiagBB()
{
const size_t nPoints = GetNPoints();
if (nPoints == 0) return 0.0;
Vec3< double > minBB = m_points[0];
Vec3< double > maxBB = m_points[0];
double x, y, z;
for (size_t v = 1; v < nPoints; v++)
{
x = m_points[v][0];
y = m_points[v][1];
z = m_points[v][2];
if (x < minBB[0]) minBB[0] = x;
else if (x > maxBB[0]) maxBB[0] = x;
if (y < minBB[1]) minBB[1] = y;
else if (y > maxBB[1]) maxBB[1] = y;
if (z < minBB[2]) minBB[2] = z;
else if (z > maxBB[2]) maxBB[2] = z;
}
return (m_diag = (maxBB - minBB).GetNorm());
}
bool Mesh::IsInside(const Vec3<double> & pt) const
{
const size_t nV = GetNPoints();
const size_t nT = GetNTriangles();
if (nV == 0 || nT == 0)
{
return false;
}
Vec3<double> ver0, ver1, ver2;
double volume;
for (size_t t = 0; t < nT; t++)
{
const Vec3<int> & tri = GetTriangle(t);
ver0 = GetPoint(tri[0]);
ver1 = GetPoint(tri[1]);
ver2 = GetPoint(tri[2]);
volume = ComputeVolume4(ver0, ver1, ver2, pt);
if (volume < 0.0)
{
return false;
}
}
return true;
}
void PolyLine2::InsertPoint( int pos, const Vec2& pt )
{
if (pos < 0) pos = 0;
if (pos > GetNPoints()) pos = GetNPoints();
m_Points.insert( m_Points.begin() + pos, pt );
}
