Cloned library of VTK-5.0.0 with extra build files for internal package management.
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/*=========================================================================
Program: Visualization Toolkit
Module: $RCSfile: vtkLine.cxx,v $
Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
All rights reserved.
See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notice for more information.
=========================================================================*/
#include "vtkLine.h"
#include "vtkCellArray.h"
#include "vtkCellData.h"
#include "vtkMath.h"
#include "vtkObjectFactory.h"
#include "vtkPointData.h"
#include "vtkPointLocator.h"
#include "vtkPoints.h"
vtkCxxRevisionMacro(vtkLine, "$Revision: 1.1 $");
vtkStandardNewMacro(vtkLine);
//----------------------------------------------------------------------------
// Construct the line with two points.
vtkLine::vtkLine()
{
this->Points->SetNumberOfPoints(2);
this->PointIds->SetNumberOfIds(2);
for (int i = 0; i < 2; i++)
{
this->Points->SetPoint(i, 0.0, 0.0, 0.0);
this->PointIds->SetId(i,0);
}
}
//----------------------------------------------------------------------------
static const int VTK_NO_INTERSECTION=0;
static const int VTK_YES_INTERSECTION=2;
static const int VTK_ON_LINE=3;
int vtkLine::EvaluatePosition(double x[3], double* closestPoint,
int& subId, double pcoords[3],
double& dist2, double *weights)
{
double a1[3], a2[3];
subId = 0;
pcoords[1] = pcoords[2] = 0.0;
this->Points->GetPoint(0, a1);
this->Points->GetPoint(1, a2);
if (closestPoint)
{
// DistanceToLine sets pcoords[0] to a value t, 0 <= t <= 1
dist2 = this->DistanceToLine(x,a1,a2,pcoords[0],closestPoint);
}
// pcoords[0] == t, need weights to be 1-t and t
weights[0] = 1.0 - pcoords[0];
weights[1] = pcoords[0];
if ( pcoords[0] < 0.0 || pcoords[0] > 1.0 )
{
return 0;
}
else
{
return 1;
}
}
//----------------------------------------------------------------------------
void vtkLine::EvaluateLocation(int& vtkNotUsed(subId), double pcoords[3],
double x[3], double *weights)
{
int i;
double a1[3], a2[3];
this->Points->GetPoint(0, a1);
this->Points->GetPoint(1, a2);
for (i=0; i<3; i++)
{
x[i] = a1[i] + pcoords[0]*(a2[i] - a1[i]);
}
weights[0] = 1.0 - pcoords[0];
weights[1] = pcoords[0];
}
//----------------------------------------------------------------------------
// Performs intersection of two finite 3D lines. An intersection is found if
// the projection of the two lines onto the plane perpendicular to the cross
// product of the two lines intersect. The parameters (u,v) are the
// parametric coordinates of the lines at the position of closest approach.
int vtkLine::Intersection (double a1[3], double a2[3],
double b1[3], double b2[3],
double& u, double& v)
{
double a21[3], b21[3], b1a1[3];
double c[2];
double *A[2], row1[2], row2[2];
// Initialize
u = v = 0.0;
// Determine line vectors.
a21[0] = a2[0] - a1[0]; b21[0] = b2[0] - b1[0]; b1a1[0] = b1[0] - a1[0];
a21[1] = a2[1] - a1[1]; b21[1] = b2[1] - b1[1]; b1a1[1] = b1[1] - a1[1];
a21[2] = a2[2] - a1[2]; b21[2] = b2[2] - b1[2]; b1a1[2] = b1[2] - a1[2];
// Compute the system (least squares) matrix.
A[0] = row1;
A[1] = row2;
row1[0] = vtkMath::Dot ( a21, a21 );
row1[1] = -vtkMath::Dot ( a21, b21 );
row2[0] = row1[1];
row2[1] = vtkMath::Dot ( b21, b21 );
// Compute the least squares system constant term.
c[0] = vtkMath::Dot ( a21, b1a1 );
c[1] = -vtkMath::Dot ( b21, b1a1 );
// Solve the system of equations
if ( vtkMath::SolveLinearSystem(A,c,2) == 0 )
{
return VTK_ON_LINE;
}
else
{
u = c[0];
v = c[1];
}
// Check parametric coordinates for intersection.
if ( (0.0 <= u) && (u <= 1.0) && (0.0 <= v) && (v <= 1.0) )
{
return VTK_YES_INTERSECTION;
}
else
{
return VTK_NO_INTERSECTION;
}
}
//----------------------------------------------------------------------------
int vtkLine::CellBoundary(int vtkNotUsed(subId), double pcoords[3],
vtkIdList *pts)
{
pts->SetNumberOfIds(1);
if ( pcoords[0] >= 0.5 )
{
pts->SetId(0,this->PointIds->GetId(1));
if ( pcoords[0] > 1.0 )
{
return 0;
}
else
{
return 1;
}
}
else
{
pts->SetId(0,this->PointIds->GetId(0));
if ( pcoords[0] < 0.0 )
{
return 0;
}
else
{
return 1;
}
}
}
//----------------------------------------------------------------------------
//
// marching lines case table
//
typedef int VERT_LIST;
typedef struct {
VERT_LIST verts[2];
} VERT_CASES;
static VERT_CASES vertCases[4]= {
{{-1,-1}},
{{1,0}},
{{0,1}},
{{-1,-1}}};
//----------------------------------------------------------------------------
void vtkLine::Contour(double value, vtkDataArray *cellScalars,
vtkPointLocator *locator, vtkCellArray *verts,
vtkCellArray *vtkNotUsed(lines),
vtkCellArray *vtkNotUsed(polys),
vtkPointData *inPd, vtkPointData *outPd,
vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd)
{
static int CASE_MASK[2] = {1,2};
int index, i, newCellId;
VERT_CASES *vertCase;
VERT_LIST *vert;
double t, x[3], x1[3], x2[3];
vtkIdType pts[1];
//
// Build the case table
//
for ( i=0, index = 0; i < 2; i++)
{
if (cellScalars->GetComponent(i,0) >= value)
{
index |= CASE_MASK[i];
}
}
vertCase = vertCases + index;
vert = vertCase->verts;
if ( vert[0] > -1 )
{
t = (value - cellScalars->GetComponent(vert[0],0)) /
(cellScalars->GetComponent(vert[1],0) -
cellScalars->GetComponent(vert[0],0));
this->Points->GetPoint(vert[0], x1);
this->Points->GetPoint(vert[1], x2);
for (i=0; i<3; i++)
{
x[i] = x1[i] + t * (x2[i] - x1[i]);
}
if ( locator->InsertUniquePoint(x, pts[0]) )
{
if ( outPd )
{
vtkIdType p1 = this->PointIds->GetId(vert[0]);
vtkIdType p2 = this->PointIds->GetId(vert[1]);
outPd->InterpolateEdge(inPd,pts[0],p1,p2,t);
}
}
newCellId = verts->InsertNextCell(1,pts);
outCd->CopyData(inCd,cellId,newCellId);
}
}
//----------------------------------------------------------------------------
// Compute distance to finite line. Returns parametric coordinate t
// and point location on line.
double vtkLine::DistanceToLine(double x[3], double p1[3], double p2[3],
double &t, double closestPoint[3])
{
double p21[3], denom, num;
double *closest;
double tolerance;
//
// Determine appropriate vectors
//
p21[0] = p2[0]- p1[0];
p21[1] = p2[1]- p1[1];
p21[2] = p2[2]- p1[2];
//
// Get parametric location
//
num = p21[0]*(x[0]-p1[0]) + p21[1]*(x[1]-p1[1]) + p21[2]*(x[2]-p1[2]);
denom = vtkMath::Dot(p21,p21);
// trying to avoid an expensive fabs
tolerance = VTK_TOL*num;
if (tolerance < 0.0)
{
tolerance = -tolerance;
}
if ( -tolerance < denom && denom < tolerance ) //numerically bad!
{
closest = p1; //arbitrary, point is (numerically) far away
}
//
// If parametric coordinate is within 0<=p<=1, then the point is closest to
// the line. Otherwise, it's closest to a point at the end of the line.
//
else if ( (t=num/denom) < 0.0 )
{
closest = p1;
}
else if ( t > 1.0 )
{
closest = p2;
}
else
{
closest = p21;
p21[0] = p1[0] + t*p21[0];
p21[1] = p1[1] + t*p21[1];
p21[2] = p1[2] + t*p21[2];
}
closestPoint[0] = closest[0];
closestPoint[1] = closest[1];
closestPoint[2] = closest[2];
return vtkMath::Distance2BetweenPoints(closest,x);
}
//----------------------------------------------------------------------------
//
// Determine the distance of the current vertex to the edge defined by
// the vertices provided. Returns distance squared. Note: line is assumed
// infinite in extent.
//
double vtkLine::DistanceToLine (double x[3], double p1[3], double p2[3])
{
int i;
double np1[3], p1p2[3], proj, den;
for (i=0; i<3; i++)
{
np1[i] = x[i] - p1[i];
p1p2[i] = p1[i] - p2[i];
}
if ( (den=vtkMath::Norm(p1p2)) != 0.0 )
{
for (i=0; i<3; i++)
{
p1p2[i] /= den;
}
}
else
{
return vtkMath::Dot(np1,np1);
}
proj = vtkMath::Dot(np1,p1p2);
return (vtkMath::Dot(np1,np1) - proj*proj);
}
//----------------------------------------------------------------------------
// Line-line intersection. Intersection has to occur within [0,1] parametric
// coordinates and with specified tolerance.
int vtkLine::IntersectWithLine(double p1[3], double p2[3], double tol, double& t,
double x[3], double pcoords[3], int& subId)
{
double a1[3], a2[3];
double projXYZ[3];
int i;
subId = 0;
pcoords[1] = pcoords[2] = 0.0;
this->Points->GetPoint(0, a1);
this->Points->GetPoint(1, a2);
if ( this->Intersection(p1, p2, a1, a2, t, pcoords[0]) ==
VTK_YES_INTERSECTION )
{
// make sure we are within tolerance
for (i=0; i<3; i++)
{
x[i] = a1[i] + pcoords[0]*(a2[i]-a1[i]);
projXYZ[i] = p1[i] + t*(p2[i]-p1[i]);
}
if ( vtkMath::Distance2BetweenPoints(x,projXYZ) <= tol*tol )
{
return 1;
}
else
{
return 0;
}
}
else //check to see if it lies within tolerance
{
// one of the parametric coords must be outside 0-1
if (t < 0.0)
{
t = 0.0;
if (vtkLine::DistanceToLine(p1,a1,a2,pcoords[0],x) <= tol*tol)
{
return 1;
}
else
{
return 0;
}
}
if (t > 1.0)
{
t = 1.0;
if (vtkLine::DistanceToLine(p2,a1,a2,pcoords[0],x) <= tol*tol)
{
return 1;
}
else
{
return 0;
}
}
if (pcoords[0] < 0.0)
{
pcoords[0] = 0.0;
if (vtkLine::DistanceToLine(a1,p1,p2,t,x) <= tol*tol)
{
return 1;
}
else
{
return 0;
}
}
if (pcoords[0] > 1.0)
{
pcoords[0] = 1.0;
if (vtkLine::DistanceToLine(a2,p1,p2,t,x) <= tol*tol)
{
return 1;
}
else
{
return 0;
}
}
}
return 0;
}
//----------------------------------------------------------------------------
int vtkLine::Triangulate(int vtkNotUsed(index), vtkIdList *ptIds,
vtkPoints *pts)
{
pts->Reset();
ptIds->Reset();
ptIds->InsertId(0,this->PointIds->GetId(0));
pts->InsertPoint(0,this->Points->GetPoint(0));
ptIds->InsertId(1,this->PointIds->GetId(1));
pts->InsertPoint(1,this->Points->GetPoint(1));
return 1;
}
//----------------------------------------------------------------------------
void vtkLine::Derivatives(int vtkNotUsed(subId),
double vtkNotUsed(pcoords)[3],
double *values,
int dim, double *derivs)
{
double x0[3], x1[3], deltaX[3];
int i, j;
this->Points->GetPoint(0, x0);
this->Points->GetPoint(1, x1);
for (i=0; i<3; i++)
{
deltaX[i] = x1[i] - x0[i];
}
for (i=0; i<dim; i++)
{
for (j=0; j<3; j++)
{
if ( deltaX[j] != 0 )
{
derivs[3*i+j] = (values[2*i+1] - values[2*i]) / deltaX[j];
}
else
{
derivs[3*i+j] =0;
}
}
}
}
//----------------------------------------------------------------------------
// support line clipping
typedef int LINE_LIST;
typedef struct {
LINE_LIST lines[2];
} LINE_CASES;
static LINE_CASES lineCases[] = {
{{ -1, -1}}, // 0
{{100, 1}}, // 1
{{ 0, 101}}, // 2
{{100, 101}}}; // 3
// Clip this line using scalar value provided. Like contouring, except
// that it cuts the line to produce other lines.
void vtkLine::Clip(double value, vtkDataArray *cellScalars,
vtkPointLocator *locator, vtkCellArray *lines,
vtkPointData *inPd, vtkPointData *outPd,
vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd,
int insideOut)
{
static int CASE_MASK[3] = {1,2};
LINE_CASES *lineCase;
int i, j, index, *vert, newCellId;
vtkIdType pts[3];
int vertexId;
double t, x1[3], x2[3], x[3];
// Build the case table
if ( insideOut )
{
for ( i=0, index = 0; i < 2; i++)
{
if (cellScalars->GetComponent(i,0) <= value)
{
index |= CASE_MASK[i];
}
}
}
else
{
for ( i=0, index = 0; i < 2; i++)
{
if (cellScalars->GetComponent(i,0) > value)
{
index |= CASE_MASK[i];
}
}
}
// Select the case based on the index and get the list of lines for this case
lineCase = lineCases + index;
vert = lineCase->lines;
// generate clipped line
if ( vert[0] > -1 )
{
for (i=0; i<2; i++) // insert line
{
// vertex exists, and need not be interpolated
if (vert[i] >= 100)
{
vertexId = vert[i] - 100;
this->Points->GetPoint(vertexId, x);
if ( locator->InsertUniquePoint(x, pts[i]) )
{
outPd->CopyData(inPd,this->PointIds->GetId(vertexId),pts[i]);
}
}
else //new vertex, interpolate
{
t = (value - cellScalars->GetComponent(0,0)) /
(cellScalars->GetComponent(1,0) - cellScalars->GetComponent(0,0));
this->Points->GetPoint(0, x1);
this->Points->GetPoint(1, x2);
for (j=0; j<3; j++)
{
x[j] = x1[j] + t * (x2[j] - x1[j]);
}
if ( locator->InsertUniquePoint(x, pts[i]) )
{
vtkIdType p1 = this->PointIds->GetId(0);
vtkIdType p2 = this->PointIds->GetId(1);
outPd->InterpolateEdge(inPd,pts[i],p1,p2,t);
}
}
}
// check for degenerate lines
if ( pts[0] != pts[1] )
{
newCellId = lines->InsertNextCell(2,pts);
outCd->CopyData(inCd,cellId,newCellId);
}
}
}
//----------------------------------------------------------------------------
//
// Compute interpolation functions
//
void vtkLine::InterpolationFunctions(double pcoords[3], double weights[2])
{
weights[0] = 1.0 - pcoords[0];
weights[1] = pcoords[0];
}
//----------------------------------------------------------------------------
static double vtkLineCellPCoords[6] = {0.0,0.0,0.0, 1.0,0.0,0.0};
double *vtkLine::GetParametricCoords()
{
return vtkLineCellPCoords;
}
//----------------------------------------------------------------------------
void vtkLine::PrintSelf(ostream& os, vtkIndent indent)
{
this->Superclass::PrintSelf(os,indent);
}