MixedDecimaterT_impl.hh

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//=============================================================================
//
//  CLASS MixedDecimaterT - IMPLEMENTATION
//
//=============================================================================
#define OPENMESH_MIXED_DECIMATER_DECIMATERT_CC
 
//== INCLUDES =================================================================
 
#include <OpenMesh/Tools/Decimater/MixedDecimaterT.hh>
 
#include <vector>
#if defined(OM_CC_MIPS)
#  include <float.h>
#else
#  include <cfloat>
#endif
 
//== NAMESPACE ===============================================================
namespace OpenMesh {
namespace Decimater {
 
//== IMPLEMENTATION ==========================================================
 
template<class Mesh>
MixedDecimaterT<Mesh>::MixedDecimaterT(Mesh& _mesh) :
  BaseDecimaterT<Mesh>(_mesh),McDecimaterT<Mesh>(_mesh), DecimaterT<Mesh>(_mesh) {
 
}
 
//-----------------------------------------------------------------------------
 
template<class Mesh>
MixedDecimaterT<Mesh>::~MixedDecimaterT() {
 
}
 
//-----------------------------------------------------------------------------
template<class Mesh>
size_t MixedDecimaterT<Mesh>::decimate(const size_t _n_collapses, const float _mc_factor, bool _only_selected) {
 
  if (_mc_factor > 1.0)
    return 0;
 
  size_t n_collapses_mc = static_cast<size_t>(_mc_factor*_n_collapses);
  size_t n_collapses_inc = static_cast<size_t>(_n_collapses - n_collapses_mc);
 
  size_t r_collapses = 0;
  if (_mc_factor > 0.0)
    r_collapses = McDecimaterT<Mesh>::decimate(n_collapses_mc,_only_selected);
 
  // returns, if the previous steps were aborted by the observer
  if (this->observer() && this->observer()->abort())
      return r_collapses;
 
  if (_mc_factor < 1.0)
    r_collapses += DecimaterT<Mesh>::decimate(n_collapses_inc,_only_selected);
 
  return r_collapses;
 
}
 
template<class Mesh>
size_t MixedDecimaterT<Mesh>::decimate_to_faces(const size_t  _n_vertices,const size_t _n_faces, const float _mc_factor , bool _only_selected){
 
  if (_mc_factor > 1.0)
    return 0;
 
  std::size_t r_collapses = 0;
  if (_mc_factor > 0.0)
  {
    bool constraintsOnly = (_n_vertices == 0) && (_n_faces == 1);
    if (!constraintsOnly) {
      size_t mesh_faces = this->mesh().n_faces();
      size_t mesh_vertices = this->mesh().n_vertices();
      //reduce the mesh only for _mc_factor
      size_t n_vertices_mc = static_cast<size_t>(mesh_vertices - _mc_factor * (mesh_vertices - _n_vertices));
      size_t n_faces_mc = static_cast<size_t>(mesh_faces - _mc_factor * (mesh_faces - _n_faces));
 
      r_collapses = McDecimaterT<Mesh>::decimate_to_faces(n_vertices_mc, n_faces_mc,_only_selected);
    } else {
 
      const size_t samples = this->samples();
 
      // MinimalSample count for the McDecimater
      const size_t min = 2;
 
      // Maximal number of samples for the McDecimater
      const size_t max = samples;
 
      // Number of incremental steps
      const size_t steps = 7;
 
      for ( size_t i = 0; i < steps; ++i ) {
 
        // Compute number of samples to be used
        size_t samples = int (double( min) + double(i)/(double(steps)-1.0) * (max-2) ) ;
 
        // We won't allow 1 here, as this is the last step in the incremental part
        float decimaterLevel = (float(i + 1)) * _mc_factor / (float(steps) );
 
        this->set_samples(samples);
        r_collapses += McDecimaterT<Mesh>::decimate_constraints_only(decimaterLevel,_only_selected);
      }
    }
  }
 
  //Update the mesh::n_vertices function, otherwise the next Decimater function will delete too much
  this->mesh().garbage_collection();
 
  // returns, if the previous steps were aborted by the observer
  if (this->observer() && this->observer()->abort())
      return r_collapses;
 
  //reduce the rest of the mesh
  if (_mc_factor < 1.0) {
    r_collapses += DecimaterT<Mesh>::decimate_to_faces(_n_vertices,_n_faces,_only_selected);
  }
 
 
  return r_collapses;
}
 
//=============================================================================
}// END_NS_MC_DECIMATER
} // END_NS_OPENMESH
//=============================================================================