otbGluPolygonDrawingHelper.cxx

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

  Program:   ORFEO Toolbox
  Language:  C++
  Date:      $Date$
  Version:   $Revision$


  Copyright (c) Centre National d'Etudes Spatiales. All rights reserved.
  See OTBCopyright.txt 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 notices for more information.

=========================================================================*/
#include <iostream>

#include "otbGluPolygonDrawingHelper.h"
#include "otbMacro.h"

// This is defined in windows only, and it is needed for FunctionPointerType
// to be properly defined.

// There are function prototype conflits under cygwin between standard w32 API
// and standard C ones
#ifndef CALLBACK
#if defined(_WINDOWS) || defined(__CYGWIN__)
#define CALLBACK __stdcall
#else
#define CALLBACK
#endif
#endif

extern "C"
{
typedef GLvoid (CALLBACK * FunctionPointerType)();

void CALLBACK CombineCallback(GLdouble coords[3], GLdouble * /*data*/[4], GLfloat /*weights*/[4], GLdouble **dataOut)
{
  GLdouble * vertex = new GLdouble[3];
  vertex[0] = coords[0];
  vertex[1] = coords[1];
  vertex[2] = coords[2];
  *dataOut = vertex;
}

void CALLBACK ErrorCallback(GLenum errorCode)
{
  const GLubyte * estring = gluErrorString(errorCode);
  std::cout << "Glu Tesselation error: " << estring << std::endl;
}

void CALLBACK BeginCallback(GLenum prim)
{
  glBegin(prim);
}
void CALLBACK EndCallback()
{
  glEnd();
}

void CALLBACK VertexCallback(void * data)
{
  glVertex3dv((GLdouble*) data);
}

} // end extern C

namespace otb
{

GluPolygonDrawingHelper::GluPolygonDrawingHelper()
{
  // Instantiation of the tesselator object
  m_PointVector.clear();
  m_GluTesselator = gluNewTess();

  // Color
  m_Color[0] = 0;
  m_Color[1] = 0;
  m_Color[2] = 0;
  m_Color[3] = 0;

  // Setting up the tesselator callbacks
  gluTessCallback(m_GluTesselator, GLU_TESS_BEGIN, (FunctionPointerType) BeginCallback);
  gluTessCallback(m_GluTesselator, GLU_TESS_END, (FunctionPointerType) EndCallback);
  gluTessCallback(m_GluTesselator, GLU_TESS_ERROR, (FunctionPointerType) ErrorCallback);
  gluTessCallback(m_GluTesselator, GLU_TESS_VERTEX, (FunctionPointerType) VertexCallback);
  gluTessCallback(m_GluTesselator, GLU_TESS_COMBINE, (FunctionPointerType) CombineCallback);
}

GluPolygonDrawingHelper::~GluPolygonDrawingHelper()
{
  gluDeleteTess(m_GluTesselator);
}

void GluPolygonDrawingHelper::SetWindingRule(GLdouble windingRule)
{
  gluTessProperty(m_GluTesselator, GLU_TESS_WINDING_RULE, windingRule);
}

void GluPolygonDrawingHelper::SetBoundaryOnly(GLdouble boundaryOnly)
{
  gluTessProperty(m_GluTesselator, GLU_TESS_BOUNDARY_ONLY, boundaryOnly);
}

void GluPolygonDrawingHelper::Color3d(double r, double g, double b)
{
  m_Color[0] = r;
  m_Color[1] = g;
  m_Color[2] = b;
  m_Color[3] = 1.;
}

void GluPolygonDrawingHelper::Color4d(double r, double g, double b, double alpha)
{
  m_Color[0] = r;
  m_Color[1] = g;
  m_Color[2] = b;
  m_Color[3] = alpha;
}

void GluPolygonDrawingHelper::Vertex2d(double x, double y)
{
  PointType p;
  p[0] = x;
  p[1] = y;
  p[2] = 0;
  m_PointVector.push_back(p);

}

void GluPolygonDrawingHelper::Vertex3d(double x, double y, double z)
{
  PointType p;
  p[0] = x;
  p[1] = y;
  p[2] = z;
  m_PointVector.push_back(p);
}

void GluPolygonDrawingHelper::RenderPolygon()
{
  // Set up a malloced space for the polygon data.
  GLdouble **               data = new GLdouble *[m_PointVector.size()];
  unsigned int              i = 0;
  PointVectorType::iterator it;
  for (it = m_PointVector.begin(); it != m_PointVector.end(); ++i, ++it)
    {
    data[i] = new GLdouble[3];
    data[i][0] = (*it)[0];
    data[i][1] = (*it)[1];
    data[i][2] = (*it)[2];
    }
  // Set the color
  glColor4d(m_Color[0], m_Color[1], m_Color[2], m_Color[3]);
  gluTessBeginPolygon(m_GluTesselator, NULL);
  gluTessBeginContour(m_GluTesselator);

  for (i = 0; i < m_PointVector.size(); ++i)
    {
    gluTessVertex(m_GluTesselator, data[i], data[i]);
    }
  gluTessEndContour(m_GluTesselator);
  gluTessEndPolygon(m_GluTesselator);

  for (i = 0; i < m_PointVector.size(); ++i)
    {
    delete[] data[i];
    }
  delete[] data;

  m_PointVector.clear();
}
} // end namespace otb