dust3d/third_party/libigl/include/igl/WindingNumberAABB.h

378 lines
11 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
// # MUTUAL DEPENDENCY ISSUE FOR HEADER ONLY VERSION
// MUST INCLUDE winding_number.h first before guard:
#include "winding_number.h"
#ifndef IGL_WINDINGNUMBERAABB_H
#define IGL_WINDINGNUMBERAABB_H
#include "WindingNumberTree.h"
namespace igl
{
template <
typename Point,
typename DerivedV,
typename DerivedF >
class WindingNumberAABB : public WindingNumberTree<Point,DerivedV,DerivedF>
{
protected:
Point min_corner;
Point max_corner;
typename DerivedV::Scalar total_positive_area;
public:
enum SplitMethod
{
CENTER_ON_LONGEST_AXIS = 0,
MEDIAN_ON_LONGEST_AXIS = 1,
NUM_SPLIT_METHODS = 2
} split_method;
public:
inline WindingNumberAABB():
total_positive_area(std::numeric_limits<typename DerivedV::Scalar>::infinity()),
split_method(MEDIAN_ON_LONGEST_AXIS)
{}
inline WindingNumberAABB(
const Eigen::MatrixBase<DerivedV> & V,
const Eigen::MatrixBase<DerivedF> & F);
inline WindingNumberAABB(
const WindingNumberTree<Point,DerivedV,DerivedF> & parent,
const Eigen::MatrixBase<DerivedF> & F);
// Initialize some things
inline void set_mesh(
const Eigen::MatrixBase<DerivedV> & V,
const Eigen::MatrixBase<DerivedF> & F);
inline void init();
inline bool inside(const Point & p) const;
inline virtual void grow();
// Compute min and max corners
inline void compute_min_max_corners();
inline typename DerivedV::Scalar max_abs_winding_number(const Point & p) const;
inline typename DerivedV::Scalar max_simple_abs_winding_number(const Point & p) const;
};
}
// Implementation
#include "winding_number.h"
#include "barycenter.h"
#include "median.h"
#include "doublearea.h"
#include "per_face_normals.h"
#include <limits>
#include <vector>
#include <iostream>
// Minimum number of faces in a hierarchy element (this is probably dependent
// on speed of machine and compiler optimization)
#ifndef WindingNumberAABB_MIN_F
# define WindingNumberAABB_MIN_F 100
#endif
template <typename Point, typename DerivedV, typename DerivedF>
inline void igl::WindingNumberAABB<Point,DerivedV,DerivedF>::set_mesh(
const Eigen::MatrixBase<DerivedV> & V,
const Eigen::MatrixBase<DerivedF> & F)
{
igl::WindingNumberTree<Point,DerivedV,DerivedF>::set_mesh(V,F);
init();
}
template <typename Point, typename DerivedV, typename DerivedF>
inline void igl::WindingNumberAABB<Point,DerivedV,DerivedF>::init()
{
using namespace Eigen;
assert(max_corner.size() == 3);
assert(min_corner.size() == 3);
compute_min_max_corners();
Eigen::Matrix<typename DerivedV::Scalar,Eigen::Dynamic,1> dblA;
doublearea(this->getV(),this->getF(),dblA);
total_positive_area = dblA.sum()/2.0;
}
template <typename Point, typename DerivedV, typename DerivedF>
inline igl::WindingNumberAABB<Point,DerivedV,DerivedF>::WindingNumberAABB(
const Eigen::MatrixBase<DerivedV> & V,
const Eigen::MatrixBase<DerivedF> & F):
WindingNumberTree<Point,DerivedV,DerivedF>(V,F),
min_corner(),
max_corner(),
total_positive_area(
std::numeric_limits<typename DerivedV::Scalar>::infinity()),
split_method(MEDIAN_ON_LONGEST_AXIS)
{
init();
}
template <typename Point, typename DerivedV, typename DerivedF>
inline igl::WindingNumberAABB<Point,DerivedV,DerivedF>::WindingNumberAABB(
const WindingNumberTree<Point,DerivedV,DerivedF> & parent,
const Eigen::MatrixBase<DerivedF> & F):
WindingNumberTree<Point,DerivedV,DerivedF>(parent,F),
min_corner(),
max_corner(),
total_positive_area(
std::numeric_limits<typename DerivedV::Scalar>::infinity()),
split_method(MEDIAN_ON_LONGEST_AXIS)
{
init();
}
template <typename Point, typename DerivedV, typename DerivedF>
inline void igl::WindingNumberAABB<Point,DerivedV,DerivedF>::grow()
{
using namespace std;
using namespace Eigen;
// Clear anything that already exists
this->delete_children();
//cout<<"cap.rows(): "<<this->getcap().rows()<<endl;
//cout<<"F.rows(): "<<this->getF().rows()<<endl;
// Base cases
if(
this->getF().rows() <= (WindingNumberAABB_MIN_F>0?WindingNumberAABB_MIN_F:0) ||
(this->getcap().rows() - 2) >= this->getF().rows())
{
// Don't grow
return;
}
// Compute longest direction
int max_d = -1;
typename DerivedV::Scalar max_len =
-numeric_limits<typename DerivedV::Scalar>::infinity();
for(int d = 0;d<min_corner.size();d++)
{
if( (max_corner[d] - min_corner[d]) > max_len )
{
max_len = (max_corner[d] - min_corner[d]);
max_d = d;
}
}
// Compute facet barycenters
Eigen::Matrix<typename DerivedV::Scalar,Eigen::Dynamic,Eigen::Dynamic> BC;
barycenter(this->getV(),this->getF(),BC);
// Blerg, why is selecting rows so difficult
typename DerivedV::Scalar split_value;
// Split in longest direction
switch(split_method)
{
case MEDIAN_ON_LONGEST_AXIS:
// Determine median
median(BC.col(max_d),split_value);
break;
default:
assert(false);
case CENTER_ON_LONGEST_AXIS:
split_value = 0.5*(max_corner[max_d] + min_corner[max_d]);
break;
}
//cout<<"c: "<<0.5*(max_corner[max_d] + min_corner[max_d])<<" "<<
// "m: "<<split_value<<endl;;
vector<int> id( this->getF().rows());
for(int i = 0;i<this->getF().rows();i++)
{
if(BC(i,max_d) <= split_value)
{
id[i] = 0; //left
}else
{
id[i] = 1; //right
}
}
const int lefts = (int) count(id.begin(),id.end(),0);
const int rights = (int) count(id.begin(),id.end(),1);
if(lefts == 0 || rights == 0)
{
// badly balanced base case (could try to recut)
return;
}
assert(lefts+rights == this->getF().rows());
DerivedF leftF(lefts, this->getF().cols());
DerivedF rightF(rights,this->getF().cols());
int left_i = 0;
int right_i = 0;
for(int i = 0;i<this->getF().rows();i++)
{
if(id[i] == 0)
{
leftF.row(left_i++) = this->getF().row(i);
}else if(id[i] == 1)
{
rightF.row(right_i++) = this->getF().row(i);
}else
{
assert(false);
}
}
assert(right_i == rightF.rows());
assert(left_i == leftF.rows());
// Finally actually grow children and Recursively grow
WindingNumberAABB<Point,DerivedV,DerivedF> * leftWindingNumberAABB =
new WindingNumberAABB<Point,DerivedV,DerivedF>(*this,leftF);
leftWindingNumberAABB->grow();
this->children.push_back(leftWindingNumberAABB);
WindingNumberAABB<Point,DerivedV,DerivedF> * rightWindingNumberAABB =
new WindingNumberAABB<Point,DerivedV,DerivedF>(*this,rightF);
rightWindingNumberAABB->grow();
this->children.push_back(rightWindingNumberAABB);
}
template <typename Point, typename DerivedV, typename DerivedF>
inline bool igl::WindingNumberAABB<Point,DerivedV,DerivedF>::inside(const Point & p) const
{
assert(p.size() == max_corner.size());
assert(p.size() == min_corner.size());
for(int i = 0;i<p.size();i++)
{
//// Perfect matching is **not** robust
//if( p(i) < min_corner(i) || p(i) >= max_corner(i))
// **MUST** be conservative
if( p(i) < min_corner(i) || p(i) > max_corner(i))
{
return false;
}
}
return true;
}
template <typename Point, typename DerivedV, typename DerivedF>
inline void igl::WindingNumberAABB<Point,DerivedV,DerivedF>::compute_min_max_corners()
{
using namespace std;
// initialize corners
for(int d = 0;d<min_corner.size();d++)
{
min_corner[d] = numeric_limits<typename Point::Scalar>::infinity();
max_corner[d] = -numeric_limits<typename Point::Scalar>::infinity();
}
this->center = Point(0,0,0);
// Loop over facets
for(int i = 0;i<this->getF().rows();i++)
{
for(int j = 0;j<this->getF().cols();j++)
{
for(int d = 0;d<min_corner.size();d++)
{
min_corner[d] =
this->getV()(this->getF()(i,j),d) < min_corner[d] ?
this->getV()(this->getF()(i,j),d) : min_corner[d];
max_corner[d] =
this->getV()(this->getF()(i,j),d) > max_corner[d] ?
this->getV()(this->getF()(i,j),d) : max_corner[d];
}
// This is biased toward vertices incident on more than one face, but
// perhaps that's good
this->center += this->getV().row(this->getF()(i,j));
}
}
// Average
this->center.array() /= this->getF().size();
//cout<<"min_corner: "<<this->min_corner.transpose()<<endl;
//cout<<"Center: "<<this->center.transpose()<<endl;
//cout<<"max_corner: "<<this->max_corner.transpose()<<endl;
//cout<<"Diag center: "<<((this->max_corner + this->min_corner)*0.5).transpose()<<endl;
//cout<<endl;
this->radius = (max_corner-min_corner).norm()/2.0;
}
template <typename Point, typename DerivedV, typename DerivedF>
inline typename DerivedV::Scalar
igl::WindingNumberAABB<Point,DerivedV,DerivedF>::max_abs_winding_number(const Point & p) const
{
using namespace std;
// Only valid if not inside
if(inside(p))
{
return numeric_limits<typename DerivedV::Scalar>::infinity();
}
// Q: we know the total positive area so what's the most this could project
// to? Remember it could be layered in the same direction.
return numeric_limits<typename DerivedV::Scalar>::infinity();
}
template <typename Point, typename DerivedV, typename DerivedF>
inline typename DerivedV::Scalar
igl::WindingNumberAABB<Point,DerivedV,DerivedF>::max_simple_abs_winding_number(
const Point & p) const
{
using namespace std;
using namespace Eigen;
// Only valid if not inside
if(inside(p))
{
return numeric_limits<typename DerivedV::Scalar>::infinity();
}
// Max simple is the same as sum of positive winding number contributions of
// bounding box
// begin precomputation
//MatrixXd BV((int)pow(2,3),3);
typedef
Eigen::Matrix<typename DerivedV::Scalar,Eigen::Dynamic,Eigen::Dynamic>
MatrixXS;
typedef
Eigen::Matrix<typename DerivedF::Scalar,Eigen::Dynamic,Eigen::Dynamic>
MatrixXF;
MatrixXS BV((int)(1<<3),3);
BV <<
min_corner[0],min_corner[1],min_corner[2],
min_corner[0],min_corner[1],max_corner[2],
min_corner[0],max_corner[1],min_corner[2],
min_corner[0],max_corner[1],max_corner[2],
max_corner[0],min_corner[1],min_corner[2],
max_corner[0],min_corner[1],max_corner[2],
max_corner[0],max_corner[1],min_corner[2],
max_corner[0],max_corner[1],max_corner[2];
MatrixXF BF(2*2*3,3);
BF <<
0,6,4,
0,2,6,
0,3,2,
0,1,3,
2,7,6,
2,3,7,
4,6,7,
4,7,5,
0,4,5,
0,5,1,
1,5,7,
1,7,3;
MatrixXS BFN;
per_face_normals(BV,BF,BFN);
// end of precomputation
// Only keep those with positive dot products
MatrixXF PBF(BF.rows(),BF.cols());
int pbfi = 0;
Point p2c = 0.5*(min_corner+max_corner)-p;
for(int i = 0;i<BFN.rows();i++)
{
if(p2c.dot(BFN.row(i)) > 0)
{
PBF.row(pbfi++) = BF.row(i);
}
}
PBF.conservativeResize(pbfi,PBF.cols());
return igl::winding_number(BV,PBF,p);
}
#endif