Logo Search packages:      
Sourcecode: blender version File versions

LOD_QSDecimator.cpp

/**
 * $Id: LOD_QSDecimator.cpp,v 1.6 2002/12/28 17:45:46 hos Exp $
 * ***** BEGIN GPL/BL DUAL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version. The Blender
 * Foundation also sells licenses for use in proprietary software under
 * the Blender License.  See http://www.blender.org/BL/ for information
 * about this.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL/BL DUAL LICENSE BLOCK *****
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "LOD_QSDecimator.h"

#include "LOD_ExternBufferEditor.h"

using namespace std;

      LOD_QSDecimator *
LOD_QSDecimator::
New(
      LOD_ManMesh2 &mesh,
      LOD_ExternNormalEditor &face_editor,
      LOD_ExternBufferEditor &extern_editor
){

      MEM_SmartPtr<LOD_QSDecimator> output 
            = new LOD_QSDecimator(mesh,face_editor,extern_editor);

      MEM_SmartPtr<LOD_EdgeCollapser > collapser(LOD_EdgeCollapser::New());
      MEM_SmartPtr<LOD_QuadricEditor> q_editor(LOD_QuadricEditor::New(mesh));

      if (
            output == NULL ||
            collapser == NULL ||
            q_editor == NULL 
      ) {
            return NULL;
      }
      output->m_collapser = collapser.Release();
      output->m_quadric_editor = q_editor.Release();
      return output.Release();
}     



      bool
LOD_QSDecimator::
Arm(
){
      MT_assert(!m_is_armed);
      bool heap_result = BuildHeap();
      if (!heap_result) {
            return false;
      }
      m_is_armed = true;
      return true;
}
      
      bool
LOD_QSDecimator::
Step(
){
      return CollapseEdge();
}


LOD_QSDecimator::
LOD_QSDecimator(
      LOD_ManMesh2 &mesh,
      LOD_ExternNormalEditor &face_editor,
      LOD_ExternBufferEditor &extern_editor
) :
      m_mesh(mesh),
      m_face_editor(face_editor),
      m_extern_editor(extern_editor),
      m_is_armed (false)
{     
      m_deg_edges.reserve(32);
      m_deg_faces.reserve(32);
      m_deg_vertices.reserve(32);
      m_update_faces.reserve(32);
      m_new_edges.reserve(32);
      m_update_vertices.reserve(32);
};

      bool
LOD_QSDecimator::
CollapseEdge(
){
      
      // find an edge to collapse
      
      // FIXME force an edge collapse
      // or return false

      std::vector<LOD_Edge> & edges = m_mesh.EdgeSet();
      std::vector<LOD_Vertex> & verts = m_mesh.VertexSet();
      std::vector<LOD_Quadric> & quadrics = m_quadric_editor->Quadrics();
      int size = edges.size();

      if (size == 0) return false;

      const int heap_top = m_heap->Top();

      if (heap_top == -1 || edges[heap_top].HeapKey() <= -MT_INFINITY) {
            return false;
      }
      
      // compute the target position
      MT_Vector3 new_vertex = m_quadric_editor->TargetVertex(edges[heap_top]);
      LOD_Quadric & q0 = quadrics[edges[heap_top].m_verts[0]];
      LOD_Quadric & q1 = quadrics[edges[heap_top].m_verts[1]];

      LOD_Vertex &v0 = verts[edges[heap_top].m_verts[0]];
      LOD_Vertex &v1 = verts[edges[heap_top].m_verts[1]];

      LOD_Quadric sum = q0;
      sum += q1;


      if (m_collapser->CollapseEdge(
                  heap_top,
                  m_mesh,
                  m_deg_edges,
                  m_deg_faces,
                  m_deg_vertices,
                  m_new_edges,
                  m_update_faces,
                  m_update_vertices
      )) {

            // assign new vertex position

             v0.pos = new_vertex;
             v1.pos = new_vertex;

            // sum the quadrics of v0 and v1
            q0 = sum;
            q1 = sum;

            // ok update the primitive properties

            m_face_editor.Update(m_update_faces);     
            m_face_editor.UpdateVertexNormals(m_update_vertices);

            // update the external vertex buffer 
            m_extern_editor.CopyModifiedVerts(m_mesh,m_update_vertices);

            // update the external face buffer
            m_extern_editor.CopyModifiedFaces(m_mesh,m_update_faces);

            // update the edge heap
            UpdateHeap(m_deg_edges,m_new_edges);

            m_quadric_editor->Remove(m_deg_vertices);
            m_face_editor.Remove(m_deg_faces);
            m_face_editor.RemoveVertexNormals(m_deg_vertices);          
                        
            // delete the primitives

            DeletePrimitives(m_deg_edges,m_deg_faces,m_deg_vertices);

      } else {
            // the edge could not be collapsed at the moment - so
            // we adjust it's priority and add it back to the heap.
            m_heap->Remove(&edges[0],0);
            edges[heap_top].HeapKey() = - MT_INFINITY;
            m_heap->Insert(&edges[0],heap_top);
      }

      //clear all the temporary buffers

      m_deg_faces.clear();
      m_deg_edges.clear();
      m_deg_vertices.clear();
      
      m_update_faces.clear();
      m_update_vertices.clear();
      m_new_edges.clear();

      return true;

}     

      void
LOD_QSDecimator::
DeletePrimitives(
      const vector<LOD_EdgeInd> & degenerate_edges,
      const vector<LOD_FaceInd> & degenerate_faces,
      const vector<LOD_VertexInd> & degenerate_vertices
) {

      // assumes that the 3 vectors are sorted in descending order.

      // Delete Degnerate primitives
      //////////////////////////////


      // delete the old edges - we have to be very careful here
      // mesh.delete() swaps edges to be deleted with the last edge in 
      // the edge buffer. However the next edge to be deleted may have
      // been the last edge in the buffer!

      // One way to solve this is to sort degenerate_edges in descending order.
      // And then delete them in that order.
      
      // it is also vital that degenerate_edges contains no duplicates

      vector<LOD_EdgeInd>::const_iterator edge_it = degenerate_edges.begin();
      vector<LOD_EdgeInd>::const_iterator edge_end = degenerate_edges.end();

      for (; edge_it != edge_end; ++edge_it) {
            m_mesh.DeleteEdge(*edge_it,m_heap);
      }



      vector<LOD_FaceInd>::const_iterator face_it = degenerate_faces.begin();
      vector<LOD_FaceInd>::const_iterator face_end = degenerate_faces.end();
      
      for (;face_it != face_end; ++face_it) {
            m_mesh.DeleteFace(m_extern_editor,*face_it);
      }

      vector<LOD_VertexInd>::const_iterator vertex_it = degenerate_vertices.begin();
      vector<LOD_VertexInd>::const_iterator vertex_end = degenerate_vertices.end();
      
      for (;vertex_it != vertex_end; ++vertex_it) {
            m_mesh.DeleteVertex(m_extern_editor,*vertex_it);
      }
}


      bool
LOD_QSDecimator::
BuildHeap(
){
      // build the quadrics 

      if (m_quadric_editor->BuildQuadrics(m_face_editor,true) == false) return false;


      m_heap = CTR_UHeap<LOD_Edge>::New();
      // load in edge pointers to the heap

      std::vector<LOD_Edge> & edge_set= m_mesh.EdgeSet();
      std::vector<LOD_Edge>::const_iterator edge_end = edge_set.end();
      std::vector<LOD_Edge>::iterator edge_start = edge_set.begin();

      std::vector<int> & heap_vector = m_heap->HeapVector();

      for (int i = 0; i < edge_set.size(); ++i) {
            edge_set[i].HeapPos() = i;
            heap_vector.push_back(i);
      }
      
      m_heap->MakeHeap(&edge_set[0]);

      return true;
}

      void
LOD_QSDecimator::
UpdateHeap(
      std::vector<LOD_EdgeInd> &deg_edges,
      std::vector<LOD_EdgeInd> &new_edges
){
      // first of all compute values for the new edges 
      // and bung them on the heap.

      std::vector<LOD_Edge>  & edge_set= m_mesh.EdgeSet();

      std::vector<LOD_EdgeInd>::const_iterator edge_it = new_edges.begin();
      std::vector<LOD_EdgeInd>::const_iterator end_it = new_edges.end();


      // insert all the new edges         
      ///////////////////////////

      // compute edge costs ffor the new edges

      m_quadric_editor->ComputeEdgeCosts(new_edges);

      // inser the new elements into the heap

      for (; edge_it != end_it; ++edge_it) {          
            m_heap->Insert(&edge_set[0],*edge_it);
      }


      // remove all the old values from the heap

      edge_it = deg_edges.begin();
      end_it = deg_edges.end();

      for (; edge_it != end_it; ++edge_it) {
            LOD_Edge &e = edge_set[*edge_it];
            m_heap->Remove(&edge_set[0],e.HeapPos());

            e.HeapPos() = 0xffffffff;

      }
}
      

Generated by  Doxygen 1.6.0   Back to index