/*===========================================================================*\
 *                                                                           *
 *                                IsoEx                                      *
 *        Copyright (C) 2002 by Computer Graphics Group, RWTH Aachen         *
 *                         www.rwth-graphics.de                              *
 *                                                                           *
 *---------------------------------------------------------------------------*
 *                                                                           *
 *                                License                                    *
 *                                                                           *
 *  This library is free software; you can redistribute it and/or modify it  *
 *  under the terms of the GNU Library General Public License as published   *
 *  by the Free Software Foundation, version 2.                              *
 *                                                                           *
 *  This library is distributed in the hope that it will be useful, but      *
 *  WITHOUT ANY WARRANTY; without even the implied warranty of               *
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU        *
 *  Library General Public License for more details.                         *
 *                                                                           *
 *  You should have received a copy of the GNU Library General Public        *
 *  License along with this library; if not, write to the Free Software      *
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.                *
 *                                                                           *
\*===========================================================================*/

//=============================================================================
//
//  CLASS MarchingCubesT - IMPLEMENTATION
//
//=============================================================================

#define ISOEX_MARCHINGCUBEST_C

//== INCLUDES =================================================================

#include "MarchingCubesT.hh"
#include "MCTablesIsoEx.hh"
#include <vector>
#include <iostream>

//== NAMESPACES ===============================================================

namespace IsoEx
{

//== IMPLEMENTATION ==========================================================


template <class Mesh, class Grid>
MarchingCubesT<Mesh,Grid>::
MarchingCubesT( const Grid& _grid, Mesh& _mesh, float _iso, const std::string &_vprop_v2edge_name )
      : grid_( _grid ),
      mesh_( _mesh ),
      iso_( _iso )
{
   if ( _vprop_v2edge_name != "" )
   {
      _mesh.add_property( vprop_v2edge_,_vprop_v2edge_name );
      use_prop_v2edge_ = true;
   }
   else use_prop_v2edge_ = false;

   CubeIterator cube_it( grid_.begin() ), cube_end( grid_.end() );
   for ( ; cube_it!=cube_end; ++cube_it )
      process_cube( *cube_it );
}


//-----------------------------------------------------------------------------


template <class Mesh, class Grid>
void
MarchingCubesT<Mesh,Grid>::
process_cube( CubeIdx _cidx )
{
   PointIdx           corner[8];
   VertexHandle       samples[12];
   unsigned char      cubetype( 0 );
   unsigned int       i;


   // get point indices of corner vertices
   for ( i=0; i<8; ++i )
      corner[i] = grid_.point_idx( _cidx, i );


   // determine cube type
   for ( i=0; i<8; ++i )
      if ( grid_.scalar_distance( corner[i] ) > iso_ )
         cubetype |= ( 1<<i );


   // trivial reject ?
   if ( cubetype == 0 || cubetype == 255 )
      return;

   // compute samples on cube's edges
   if ( edgeTable[cubetype]&1 )    samples[0]  = add_vertex( corner[0], corner[1] );
   if ( edgeTable[cubetype]&2 )    samples[1]  = add_vertex( corner[1], corner[2] );
   if ( edgeTable[cubetype]&4 )    samples[2]  = add_vertex( corner[3], corner[2] );
   if ( edgeTable[cubetype]&8 )    samples[3]  = add_vertex( corner[0], corner[3] );
   if ( edgeTable[cubetype]&16 )   samples[4]  = add_vertex( corner[4], corner[5] );
   if ( edgeTable[cubetype]&32 )   samples[5]  = add_vertex( corner[5], corner[6] );
   if ( edgeTable[cubetype]&64 )   samples[6]  = add_vertex( corner[7], corner[6] );
   if ( edgeTable[cubetype]&128 )  samples[7]  = add_vertex( corner[4], corner[7] );
   if ( edgeTable[cubetype]&256 )  samples[8]  = add_vertex( corner[0], corner[4] );
   if ( edgeTable[cubetype]&512 )  samples[9]  = add_vertex( corner[1], corner[5] );
   if ( edgeTable[cubetype]&1024 ) samples[10] = add_vertex( corner[2], corner[6] );
   if ( edgeTable[cubetype]&2048 ) samples[11] = add_vertex( corner[3], corner[7] );



   // connect samples by triangles
   for ( i=0; triTable[cubetype][0][i] != -1; i+=3 )
      mesh_.add_face( samples[triTable[cubetype][0][i  ]],
                      samples[triTable[cubetype][0][i+1]],
                      samples[triTable[cubetype][0][i+2]] );
}


//-----------------------------------------------------------------------------


template <class Mesh, class Grid>
typename MarchingCubesT<Mesh,Grid>::VertexHandle
MarchingCubesT<Mesh,Grid>::
add_vertex( PointIdx _p0, PointIdx _p1 )
{
   // find vertex if it has been computed already
   VertexHandle   vh = edge2vertex_.find( _p0, _p1 );
   if ( vh.is_valid() )  return vh;

   // generate new vertex
   const typename Mesh::Point&  p0( grid_.point( _p0 ) );
   const typename Mesh::Point&  p1( grid_.point( _p1 ) );

   float s0 = grid_.scalar_distance( _p0 );
   float s1 = grid_.scalar_distance( _p1 );
   if ( fabs( s1-s0 ) > 0.00000001 )
   {
      float t  = ( iso_-s0 ) / ( s1-s0 );
      vh = mesh_.add_vertex( typename Mesh::Point(p0 + ( p1-p0 )*t) );
      if ( use_prop_v2edge_ )
         mesh_.property( vprop_v2edge_,vh ) = EdgeKey<PointIdx>( _p0, _p1 );

      edge2vertex_.insert( _p0, _p1, vh );
      return vh;
   }
   else
   {
      std::cout << s0 << ", " <<s1 <<"!!!!!!!!!!!!!!!!!" <<( s1 - s0 ) << std::endl;
      return vh;
   }
}


//=============================================================================
} // namespace IsoEx
//=============================================================================