470 lines
22 KiB
C++
470 lines
22 KiB
C++
/****************************************************************************
|
|
* VCGLib o o *
|
|
* Visual and Computer Graphics Library o o *
|
|
* _ O _ *
|
|
* Copyright(C) 2004 \/)\/ *
|
|
* Visual Computing Lab /\/| *
|
|
* ISTI - Italian National Research Council | *
|
|
* \ *
|
|
* All rights reserved. *
|
|
* *
|
|
* 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. *
|
|
* *
|
|
* 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 (http://www.gnu.org/licenses/gpl.txt) *
|
|
* for more details. *
|
|
* *
|
|
****************************************************************************/
|
|
/***************************************************************************/
|
|
|
|
|
|
#ifndef __VCG_EXTENDED_MARCHING_CUBES
|
|
#define __VCG_EXTENDED_MARCHING_CUBES
|
|
|
|
#include <float.h>
|
|
#include <vcg/simplex/face/topology.h>
|
|
#include <vcg/complex/algorithms/update/normal.h>
|
|
#include <vcg/complex/algorithms/update/topology.h>
|
|
#include <vcg/complex/algorithms/clean.h>
|
|
#include "emc_lookup_table.h"
|
|
#include <eigenlib/Eigen/SVD>
|
|
|
|
namespace vcg
|
|
{
|
|
namespace tri
|
|
{
|
|
// Doxygen documentation
|
|
/** \addtogroup trimesh */
|
|
/*@{*/
|
|
|
|
/*
|
|
* Cube description:
|
|
* 3 ________ 2 _____2__
|
|
* /| /| / | /|
|
|
* / | / | 11/ 3 10/ |
|
|
* 7 /_______ / | /__6_|__ / |1
|
|
* | | |6 | | | |
|
|
* | 0|__|_____|1 | |__|_0|__|
|
|
* | / | / 7 8/ 5 /
|
|
* | / | / | / | /9
|
|
* |/_______|/ |/___4___|/
|
|
* 4 5
|
|
*/
|
|
|
|
//! This class implements the Extended Marching Cubes algorithm.
|
|
/*!
|
|
* The implementation is enough generic: this class works only on one volume cell for each
|
|
* call to <CODE>ProcessCell</CODE>. Using the field value at the cell corners, it adds to the
|
|
* mesh the triangles set approximating the surface that cross that cell.
|
|
* @param TRIMESH_TYPE (Template parameter) the mesh type that will be constructed
|
|
* @param WALKER_TYPE (Template parameter) the class that implements the traversal ordering of the volume.
|
|
**/
|
|
template<class TRIMESH_TYPE, class WALKER_TYPE>
|
|
class ExtendedMarchingCubes
|
|
{
|
|
public:
|
|
#if defined(__GNUC__)
|
|
typedef unsigned int size_t;
|
|
#else
|
|
#ifdef _WIN64
|
|
typedef unsigned __int64 size_t;
|
|
#else
|
|
typedef _W64 unsigned int size_t;
|
|
#endif
|
|
#endif
|
|
typedef typename vcg::tri::Allocator< TRIMESH_TYPE > AllocatorType;
|
|
typedef typename TRIMESH_TYPE::ScalarType ScalarType;
|
|
typedef typename TRIMESH_TYPE::VertexType VertexType;
|
|
typedef typename TRIMESH_TYPE::VertexPointer VertexPointer;
|
|
typedef typename TRIMESH_TYPE::VertexIterator VertexIterator;
|
|
typedef typename TRIMESH_TYPE::FaceType FaceType;
|
|
typedef typename TRIMESH_TYPE::FacePointer FacePointer;
|
|
typedef typename TRIMESH_TYPE::FaceIterator FaceIterator;
|
|
typedef typename TRIMESH_TYPE::CoordType CoordType;
|
|
typedef typename TRIMESH_TYPE::CoordType* CoordPointer;
|
|
|
|
struct LightEdge
|
|
{
|
|
LightEdge(size_t _face, size_t _edge):face(_face), edge(_edge) { }
|
|
size_t face, edge;
|
|
};
|
|
|
|
/*!
|
|
* Constructor
|
|
* \param mesh The mesh that will be constructed
|
|
* \param volume The volume describing the field
|
|
* \param walker The class implementing the traversal policy
|
|
* \param angle The feature detection threshold misuring the sharpness of a feature(default is 30 degree)
|
|
*/
|
|
ExtendedMarchingCubes(TRIMESH_TYPE &mesh, WALKER_TYPE &walker, ScalarType angle=30)
|
|
{
|
|
_mesh = &mesh;
|
|
_walker = &walker;
|
|
_featureAngle = vcg::math::ToRad(angle);
|
|
_initialized = _finalized = false;
|
|
};
|
|
|
|
/*!
|
|
* Execute the initialiazation.
|
|
* This method must be executed before the first call to <CODE>ApplyEMC</CODE>
|
|
*/
|
|
void Initialize()
|
|
{
|
|
assert(!_initialized && !_finalized);
|
|
_featureFlag = VertexType::NewBitFlag();
|
|
_initialized = true;
|
|
};
|
|
|
|
/*!
|
|
*
|
|
* This method must be executed after the last call to <CODE>ApplyEMC</CODE>
|
|
*/
|
|
void Finalize()
|
|
{
|
|
assert(_initialized && !_finalized);
|
|
FlipEdges();
|
|
|
|
VertexIterator v_iter = _mesh->vert.begin();
|
|
VertexIterator v_end = _mesh->vert.end();
|
|
for ( ; v_iter!=v_end; v_iter++)
|
|
v_iter->ClearUserBit( _featureFlag );
|
|
VertexType::DeleteBitFlag( _featureFlag );
|
|
_featureFlag = 0;
|
|
_mesh = NULL;
|
|
_walker = NULL;
|
|
_finalized = true;
|
|
};
|
|
|
|
/*!
|
|
* Apply the <I>extended marching cubes</I> algorithm to the volume cell identified by the two points <CODE>min</CODE> and <CODE>max</CODE>.
|
|
* All the three coordinates of the first point must be smaller than the respectives three coordinatas of the second point.
|
|
* \param min the first point
|
|
* \param max the second point
|
|
*/
|
|
void ProcessCell(const vcg::Point3i &min, const vcg::Point3i &max)
|
|
{
|
|
assert(_initialized && !_finalized);
|
|
assert(min[0]<max[0] && min[1]<max[1] && min[2]<max[2]);
|
|
_corners[0].X()=min.X(); _corners[0].Y()=min.Y(); _corners[0].Z()=min.Z();
|
|
_corners[1].X()=max.X(); _corners[1].Y()=min.Y(); _corners[1].Z()=min.Z();
|
|
_corners[2].X()=max.X(); _corners[2].Y()=max.Y(); _corners[2].Z()=min.Z();
|
|
_corners[3].X()=min.X(); _corners[3].Y()=max.Y(); _corners[3].Z()=min.Z();
|
|
_corners[4].X()=min.X(); _corners[4].Y()=min.Y(); _corners[4].Z()=max.Z();
|
|
_corners[5].X()=max.X(); _corners[5].Y()=min.Y(); _corners[5].Z()=max.Z();
|
|
_corners[6].X()=max.X(); _corners[6].Y()=max.Y(); _corners[6].Z()=max.Z();
|
|
_corners[7].X()=min.X(); _corners[7].Y()=max.Y(); _corners[7].Z()=max.Z();
|
|
|
|
unsigned char cubetype = 0;
|
|
if ((_field[0] = _walker->V(_corners[0].X(), _corners[0].Y(), _corners[0].Z())) >= 0) cubetype+= 1;
|
|
if ((_field[1] = _walker->V(_corners[1].X(), _corners[1].Y(), _corners[1].Z())) >= 0) cubetype+= 2;
|
|
if ((_field[2] = _walker->V(_corners[2].X(), _corners[2].Y(), _corners[2].Z())) >= 0) cubetype+= 4;
|
|
if ((_field[3] = _walker->V(_corners[3].X(), _corners[3].Y(), _corners[3].Z())) >= 0) cubetype+= 8;
|
|
if ((_field[4] = _walker->V(_corners[4].X(), _corners[4].Y(), _corners[4].Z())) >= 0) cubetype+= 16;
|
|
if ((_field[5] = _walker->V(_corners[5].X(), _corners[5].Y(), _corners[5].Z())) >= 0) cubetype+= 32;
|
|
if ((_field[6] = _walker->V(_corners[6].X(), _corners[6].Y(), _corners[6].Z())) >= 0) cubetype+= 64;
|
|
if ((_field[7] = _walker->V(_corners[7].X(), _corners[7].Y(), _corners[7].Z())) >= 0) cubetype+=128;
|
|
|
|
if (cubetype==0 || cubetype==255)
|
|
return;
|
|
|
|
size_t vertices_idx[12];
|
|
memset(vertices_idx, -1, 12*sizeof(size_t));
|
|
int code = EMCLookUpTable::EdgeTable(cubetype);
|
|
VertexPointer vp = NULL;
|
|
if ( 1&code ) { _walker->GetXIntercept(_corners[0], _corners[1], vp); vertices_idx[ 0] = vp - &_mesh->vert[0]; }
|
|
if ( 2&code ) { _walker->GetYIntercept(_corners[1], _corners[2], vp); vertices_idx[ 1] = vp - &_mesh->vert[0]; }
|
|
if ( 4&code ) { _walker->GetXIntercept(_corners[3], _corners[2], vp); vertices_idx[ 2] = vp - &_mesh->vert[0]; }
|
|
if ( 8&code ) { _walker->GetYIntercept(_corners[0], _corners[3], vp); vertices_idx[ 3] = vp - &_mesh->vert[0]; }
|
|
if ( 16&code ) { _walker->GetXIntercept(_corners[4], _corners[5], vp); vertices_idx[ 4] = vp - &_mesh->vert[0]; }
|
|
if ( 32&code ) { _walker->GetYIntercept(_corners[5], _corners[6], vp); vertices_idx[ 5] = vp - &_mesh->vert[0]; }
|
|
if ( 64&code ) { _walker->GetXIntercept(_corners[7], _corners[6], vp); vertices_idx[ 6] = vp - &_mesh->vert[0]; }
|
|
if ( 128&code ) { _walker->GetYIntercept(_corners[4], _corners[7], vp); vertices_idx[ 7] = vp - &_mesh->vert[0]; }
|
|
if ( 256&code ) { _walker->GetZIntercept(_corners[0], _corners[4], vp); vertices_idx[ 8] = vp - &_mesh->vert[0]; }
|
|
if ( 512&code ) { _walker->GetZIntercept(_corners[1], _corners[5], vp); vertices_idx[ 9] = vp - &_mesh->vert[0]; }
|
|
if (1024&code ) { _walker->GetZIntercept(_corners[2], _corners[6], vp); vertices_idx[10] = vp - &_mesh->vert[0]; }
|
|
if (2048&code ) { _walker->GetZIntercept(_corners[3], _corners[7], vp); vertices_idx[11] = vp - &_mesh->vert[0]; }
|
|
|
|
int m, n, vertices_num;
|
|
int components = EMCLookUpTable::TriTable(cubetype, 1)[0]; //unsigned int components = triTable[cubetype][1][0];
|
|
int *indices = &EMCLookUpTable::TriTable(cubetype, 1)[components+1]; //int *indices = &EMCLookUpTable::TriTable(cubetype, 1, components+1);
|
|
|
|
std::vector< size_t > vertices_list;
|
|
for (m=1; m<=components; m++)
|
|
{
|
|
// current sheet contains vertices_num vertices
|
|
vertices_num = EMCLookUpTable::TriTable(cubetype, 1)[m]; //vertices_num = triTable[cubetype][1][m];
|
|
|
|
// collect vertices
|
|
vertices_list.clear();
|
|
for (n=0; n<vertices_num; ++n)
|
|
vertices_list.push_back( vertices_idx[ indices[n] ] );
|
|
|
|
VertexPointer feature = FindFeature( vertices_list );
|
|
if (feature != NULL) // i.e. is a valid vertex
|
|
{
|
|
// feature -> create triangle fan around feature vertex
|
|
size_t feature_idx = feature - &_mesh->vert[0];
|
|
size_t face_idx = _mesh->face.size();
|
|
vertices_list.push_back( vertices_list[0] );
|
|
AllocatorType::AddFaces(*_mesh, (int) vertices_num);
|
|
for (int j=0; j<vertices_num; ++j, face_idx++)
|
|
{
|
|
_mesh->face[face_idx].V(0) = &_mesh->vert[ vertices_list[j ] ];
|
|
_mesh->face[face_idx].V(1) = &_mesh->vert[ vertices_list[j+1] ];
|
|
_mesh->face[face_idx].V(2) = &_mesh->vert[ feature_idx ];
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// no feature -> old marching cubes triangle table
|
|
for (int j=0; EMCLookUpTable::PolyTable(vertices_num, j) != -1; j+=3) //for (int j=0; polyTable[vertices_num][j] != -1; j+=3)
|
|
{
|
|
size_t face_idx = _mesh->face.size();
|
|
AllocatorType::AddFaces(*_mesh, 1);
|
|
//_mesh->face[ face_idx].V(0) = &_mesh->vert[ vertices_idx[ indices[ polyTable[vertices_num][j ] ] ] ];
|
|
//_mesh->face[ face_idx].V(1) = &_mesh->vert[ vertices_idx[ indices[ polyTable[vertices_num][j+1] ] ] ];
|
|
//_mesh->face[ face_idx].V(2) = &_mesh->vert[ vertices_idx[ indices[ polyTable[vertices_num][j+2] ] ] ];
|
|
_mesh->face[ face_idx].V(0) = &_mesh->vert[ vertices_idx[ indices[ EMCLookUpTable::PolyTable(vertices_num, j ) ] ] ];
|
|
_mesh->face[ face_idx].V(1) = &_mesh->vert[ vertices_idx[ indices[ EMCLookUpTable::PolyTable(vertices_num, j+1) ] ] ];
|
|
_mesh->face[ face_idx].V(2) = &_mesh->vert[ vertices_idx[ indices[ EMCLookUpTable::PolyTable(vertices_num, j+2) ] ] ];
|
|
}
|
|
}
|
|
indices += vertices_num;
|
|
|
|
}
|
|
}; // end of ApplyEMC
|
|
|
|
private:
|
|
/*!
|
|
*/
|
|
WALKER_TYPE *_walker;
|
|
/*!
|
|
*/
|
|
TRIMESH_TYPE *_mesh;
|
|
/*!
|
|
*/
|
|
bool _initialized;;
|
|
/*!
|
|
*/
|
|
bool _finalized;
|
|
/*!
|
|
* The feature detection threshold misuring the sharpness of a feature
|
|
*/
|
|
ScalarType _featureAngle;
|
|
/*!
|
|
* The flag used for marking the feature vertices.
|
|
*/
|
|
int _featureFlag;
|
|
/*!
|
|
* Array of the 8 corners of the volume cell being processed
|
|
*/
|
|
vcg::Point3i _corners[8];
|
|
/*!
|
|
* The field value at the cell corners
|
|
*/
|
|
ScalarType _field[8];
|
|
|
|
|
|
/*!
|
|
* Tests if the surface patch crossing the current cell contains a sharp feature
|
|
* \param vertices_idx The list of vertex indices intersecting the edges of the current cell
|
|
* \return The pointer to the new Vertex if a feature is detected; NULL otherwise.
|
|
*/
|
|
VertexPointer FindFeature(const std::vector<size_t> &vertices_idx)
|
|
{
|
|
unsigned int i, j, rank;
|
|
size_t vertices_num = (size_t) vertices_idx.size();
|
|
|
|
CoordType *points = new CoordType[ vertices_num ];
|
|
CoordType *normals = new CoordType[ vertices_num ];
|
|
Box3<ScalarType> bb;
|
|
for (i=0; i<vertices_num; i++)
|
|
{
|
|
points[i] = _mesh->vert[ vertices_idx[i] ].P();
|
|
normals[i].Import(_mesh->vert[ vertices_idx[i] ].N());
|
|
bb.Add(points[i]);
|
|
}
|
|
|
|
// move barycenter of points into (0, 0, 0)
|
|
CoordType center((ScalarType) 0.0, (ScalarType) 0.0, (ScalarType) 0.0);
|
|
for (i=0; i<vertices_num; ++i)
|
|
center += points[i];
|
|
center /= (ScalarType) vertices_num;
|
|
for (i=0; i<vertices_num; ++i)
|
|
points[i] -= center;
|
|
|
|
// normal angle criterion
|
|
double c, minC, maxC;
|
|
CoordType axis;
|
|
for (minC=1.0, i=0; i<vertices_num-1; ++i)
|
|
{
|
|
for (j=i+1; j<vertices_num; ++j)
|
|
{
|
|
c = normals[i]*normals[j];
|
|
if (c < minC)
|
|
{
|
|
minC = c;
|
|
axis = normals[i] ^ normals[j];
|
|
}
|
|
}
|
|
} //end for (minC=1.0, i=0; i<vertNumber; ++i)
|
|
|
|
if (minC > cos(_featureAngle))
|
|
return NULL; // invalid vertex
|
|
|
|
// ok, we have a feature: is it edge or corner, i.e. rank 2 or 3 ?
|
|
axis.Normalize();
|
|
for (minC=1.0, maxC=-1.0, i=0; i<vertices_num; ++i)
|
|
{
|
|
c = axis * normals[i];
|
|
if (c < minC) minC = c;
|
|
if (c > maxC) maxC = c;
|
|
}
|
|
c = std::max< double >(fabs(minC), fabs(maxC));
|
|
c = sqrt(1.0-c*c);
|
|
rank = (c > cos(_featureAngle) ? 2 : 3);
|
|
|
|
// setup linear system (find intersection of tangent planes)
|
|
//--vcg::ndim::Matrix<double> A((unsigned int) vertices_num, 3);
|
|
Eigen::MatrixXd A(vertices_num,3);
|
|
|
|
//--double *b = new double[ vertices_num ];
|
|
Eigen::MatrixXd b(vertices_num,1);
|
|
|
|
for (i=0; i<vertices_num; ++i)
|
|
{
|
|
//--A[i][0] = normals[i][0];
|
|
//--A[i][1] = normals[i][1];
|
|
//--A[i][2] = normals[i][2];
|
|
//--b[i] = (points[i] * normals[i]);
|
|
A(i,0) = normals[i][0];
|
|
A(i,1) = normals[i][1];
|
|
A(i,2) = normals[i][2];
|
|
b(i) = (points[i] * normals[i]);
|
|
}
|
|
|
|
// SVD of matrix A
|
|
Eigen::JacobiSVD<Eigen::MatrixXd> svd(A, Eigen::ComputeThinU | Eigen::ComputeThinV);
|
|
Eigen::MatrixXd sol(3,1);
|
|
sol=svd.solve(b);
|
|
|
|
// vcg::ndim::Matrix<double> V(3, 3);
|
|
// double *w = new double[vertices_num];
|
|
// vcg::SingularValueDecomposition< typename vcg::ndim::Matrix<double> > (A, w, V, LeaveUnsorted, 100);
|
|
|
|
// rank == 2 -> suppress smallest singular value
|
|
// if (rank == 2)
|
|
// {
|
|
// double smin = DBL_MAX; // the max value, as defined in <float.h>
|
|
// unsigned int sminid = 0;
|
|
// unsigned int srank = std::min< unsigned int >(vertices_num, 3u);
|
|
|
|
// for (i=0; i<srank; ++i)
|
|
// {
|
|
// if (w[i] < smin)
|
|
// {
|
|
// smin = w[i];
|
|
// sminid = i;
|
|
// }
|
|
// }
|
|
// w[sminid] = 0.0;
|
|
// }
|
|
//
|
|
// // SVD backsubstitution -> least squares, least norm solution x
|
|
// double *x = new double[3];
|
|
// vcg::SingularValueBacksubstitution< vcg::ndim::Matrix<double> >(A, w, V, x, b);
|
|
|
|
// transform x to world coords
|
|
//--CoordType point((ScalarType) x[0], (ScalarType) x[1], (ScalarType) x[2]);
|
|
CoordType point((ScalarType) sol(0), (ScalarType) sol(1), (ScalarType) sol(2));
|
|
point += center;
|
|
|
|
// Safety check if the feature point found by svd is
|
|
// out of the bbox of the vertices perhaps it is better to put it back in the center...
|
|
if(!bb.IsIn(point)) point = center;
|
|
|
|
// insert the feature-point
|
|
VertexPointer mean_point = &*AllocatorType::AddVertices( *_mesh, 1);
|
|
mean_point->SetUserBit(_featureFlag);
|
|
mean_point->P() = point;
|
|
mean_point->N().SetZero();
|
|
// delete []x;
|
|
delete []points;
|
|
delete []normals;
|
|
return mean_point;
|
|
} // end of FindFeature
|
|
|
|
/*!
|
|
* Postprocessing step performed during the finalization tha flip some of the mesh edges.
|
|
* The flipping criterion is quite simple: each edge is flipped if it will connect two
|
|
* feature samples after the flip.
|
|
*/
|
|
void FlipEdges()
|
|
{
|
|
std::vector< LightEdge > edges;
|
|
for (FaceIterator fi = _mesh->face.begin(); fi!=_mesh->face.end(); fi++)
|
|
{
|
|
size_t i = tri::Index(*_mesh,*fi);
|
|
if (fi->V(1) > fi->V(0)) edges.push_back( LightEdge(i,0) );
|
|
if (fi->V(2) > fi->V(1)) edges.push_back( LightEdge(i,1) );
|
|
if (fi->V(0) > fi->V(2)) edges.push_back( LightEdge(i,2) );
|
|
}
|
|
vcg::tri::UpdateTopology< TRIMESH_TYPE >::FaceFace( *_mesh );
|
|
|
|
// Select all the triangles that has a vertex shared with a non manifold edge.
|
|
int nonManifEdge = tri::Clean< TRIMESH_TYPE >::CountNonManifoldEdgeFF(*_mesh,true);
|
|
if(nonManifEdge >0)
|
|
tri::UpdateSelection< TRIMESH_TYPE >::FaceFromVertexLoose(*_mesh);
|
|
//qDebug("Got %i non manif edges",nonManifEdge);
|
|
|
|
typename std::vector< LightEdge >::iterator e_it = edges.begin();
|
|
typename std::vector< LightEdge >::iterator e_end = edges.end();
|
|
|
|
FacePointer g, f;
|
|
int w, z;
|
|
for( ; e_it!=e_end; e_it++)
|
|
{
|
|
f = &_mesh->face[e_it->face];
|
|
z = (int) e_it->edge;
|
|
|
|
// v2------v1 swap the diagonal only if v2 and v3 are feature and v0 and v1 are not.
|
|
// | / |
|
|
// | / |
|
|
// v0------v3
|
|
if (!(f->IsS()) && vcg::face::CheckFlipEdge< FaceType >(*f, z))
|
|
{
|
|
VertexPointer v0, v1, v2, v3;
|
|
v0 = f->V(z);
|
|
v1 = f->V1(z);
|
|
v2 = f->V2(z);
|
|
g = f->FFp(z);
|
|
w = f->FFi(z);
|
|
v3 = g->V2(w);
|
|
bool b0, b1, b2, b3;
|
|
b0 = !v0->IsUserBit(_featureFlag) ;
|
|
b1 = !v1->IsUserBit(_featureFlag) ;
|
|
b2 = v2->IsUserBit(_featureFlag) ;
|
|
b3 = v3->IsUserBit(_featureFlag) ;
|
|
if( b0 && b1 && b2 && b3)
|
|
vcg::face::FlipEdge< FaceType >(*f, z);
|
|
|
|
} // end if (vcg::face::CheckFlipEdge< _Face >(*f, z))
|
|
} // end for( ; e_it!=e_end; e_it++)
|
|
|
|
} //end of FlipEdges
|
|
|
|
|
|
}; // end of class ExtendedMarchingCubes
|
|
// /*! @} */
|
|
// end of Doxygen documentation
|
|
|
|
} // end of namespace tri
|
|
}; // end of namespace vcg
|
|
|
|
#endif // __VCG_EXTENDED_MARCHING_CUBES
|