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Common/vtkPolygon.h

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/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkPolygon.h,v $
  Language:  C++


Copyright (c) 1993-2001 Ken Martin, Will Schroeder, Bill Lorensen 
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

 * Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.

 * Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

 * Neither name of Ken Martin, Will Schroeder, or Bill Lorensen nor the names
   of any contributors may be used to endorse or promote products derived
   from this software without specific prior written permission.

 * Modified source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/
#ifndef __vtkPolygon_h
#define __vtkPolygon_h

#include "vtkCell.h"
#include "vtkPoints.h"
#include "vtkLine.h"
#include "vtkTriangle.h"
#include "vtkQuad.h"

class VTK_COMMON_EXPORT vtkPolygon : public vtkCell
{
public:
  static vtkPolygon *New();
  vtkTypeMacro(vtkPolygon,vtkCell);


  vtkCell *MakeObject();
  int GetCellType() {return VTK_POLYGON;};
  int GetCellDimension() {return 2;};
  int GetNumberOfEdges() {return this->GetNumberOfPoints();};
  int GetNumberOfFaces() {return 0;};
  vtkCell *GetEdge(int edgeId);
  vtkCell *GetFace(int) {return 0;};
  int CellBoundary(int subId, float pcoords[3], vtkIdList *pts);
  void Contour(float value, vtkDataArray *cellScalars, 
               vtkPointLocator *locator,vtkCellArray *verts, 
               vtkCellArray *lines, vtkCellArray *polys,
               vtkPointData *inPd, vtkPointData *outPd,
               vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd);
  void Clip(float value, vtkDataArray *cellScalars, 
            vtkPointLocator *locator, vtkCellArray *tris,
            vtkPointData *inPd, vtkPointData *outPd,
            vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd,
            int insideOut);
  int EvaluatePosition(float x[3], float* closestPoint,
                       int& subId, float pcoords[3],
                       float& dist2, float *weights);
  void EvaluateLocation(int& subId, float pcoords[3], float x[3],
                        float *weights);
  int IntersectWithLine(float p1[3], float p2[3], float tol, float& t,
                        float x[3], float pcoords[3], int& subId);
  int Triangulate(int index, vtkIdList *ptIds, vtkPoints *pts);
  void Derivatives(int subId, float pcoords[3], float *values, 
                   int dim, float *derivs);


  static void ComputeNormal(vtkPoints *p, int numPts, vtkIdType *pts,
                            float n[3]);
  static void ComputeNormal(vtkPoints *p, float n[3]);
  
  static void ComputeNormal(int numPts, float *pts, float n[3]);

  void ComputeWeights(float x[3], float *weights);



  int ParameterizePolygon(float p0[3], float p10[3], float &l10, 
                          float p20[3], float &l20, float n[3]);
  

  static int PointInPolygon(float x[3], int numPts, float *pts, 
                            float bounds[6], float n[3]);  

  int Triangulate(vtkIdList *outTris);
  

  static int IntersectPolygonWithPolygon(int npts, float *pts, float bounds[6],
                                         int npts2, float *pts2, 
                                         float bounds2[3], float tol,
                                         float x[3]);

protected:
  vtkPolygon();
  ~vtkPolygon();

  // variables used by instances of this class
  float   Tolerance; // Intersection tolerance
  int     SuccessfulTriangulation; // Stops recursive tri. if necessary
  float   Normal[3]; //polygon normal
  vtkIdList *Tris;
  vtkTriangle *Triangle;
  vtkQuad *Quad;
  vtkFloatArray *TriScalars;
  vtkLine *Line;

  // Helper methods for triangulation------------------------------
  int EarCutTriangulation();

private:
  vtkPolygon(const vtkPolygon&);  // Not implemented.
  void operator=(const vtkPolygon&);  // Not implemented.
};

#endif

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