OrcaSlicer/src/libigl/igl/cotmatrix_entries.cpp
tamasmeszaros 2ae2672ee9 Building igl statically and moving to the dep scripts
Fixing dep build script on Windows and removing some warnings.

Use bundled igl by default.

Not building with the dependency scripts if not explicitly stated. This way, it will stay in
Fix the libigl patch to include C source files in header only mode.
2019-06-19 14:52:55 +02:00

110 lines
4.9 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 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/.
#include "cotmatrix_entries.h"
#include "doublearea.h"
#include "squared_edge_lengths.h"
#include "edge_lengths.h"
#include "face_areas.h"
#include "volume.h"
#include "dihedral_angles.h"
#include "verbose.h"
template <typename DerivedV, typename DerivedF, typename DerivedC>
IGL_INLINE void igl::cotmatrix_entries(
const Eigen::MatrixBase<DerivedV>& V,
const Eigen::MatrixBase<DerivedF>& F,
Eigen::PlainObjectBase<DerivedC>& C)
{
using namespace std;
using namespace Eigen;
// simplex size (3: triangles, 4: tetrahedra)
int simplex_size = F.cols();
// Number of elements
int m = F.rows();
// Law of cosines + law of sines
switch(simplex_size)
{
case 3:
{
// Triangles
//Compute Squared Edge lengths
Matrix<typename DerivedC::Scalar,Dynamic,3> l2;
igl::squared_edge_lengths(V,F,l2);
//Compute Edge lengths
Matrix<typename DerivedC::Scalar,Dynamic,3> l;
l = l2.array().sqrt();
// double area
Matrix<typename DerivedC::Scalar,Dynamic,1> dblA;
doublearea(l,0.,dblA);
// cotangents and diagonal entries for element matrices
// correctly divided by 4 (alec 2010)
C.resize(m,3);
for(int i = 0;i<m;i++)
{
C(i,0) = (l2(i,1) + l2(i,2) - l2(i,0))/dblA(i)/4.0;
C(i,1) = (l2(i,2) + l2(i,0) - l2(i,1))/dblA(i)/4.0;
C(i,2) = (l2(i,0) + l2(i,1) - l2(i,2))/dblA(i)/4.0;
}
break;
}
case 4:
{
// edge lengths numbered same as opposite vertices
Matrix<typename DerivedC::Scalar,Dynamic,6> l;
edge_lengths(V,F,l);
Matrix<typename DerivedC::Scalar,Dynamic,4> s;
face_areas(l,s);
Matrix<typename DerivedC::Scalar,Dynamic,6> cos_theta,theta;
dihedral_angles_intrinsic(l,s,theta,cos_theta);
// volume
Matrix<typename DerivedC::Scalar,Dynamic,1> vol;
volume(l,vol);
// Law of sines
// http://mathworld.wolfram.com/Tetrahedron.html
Matrix<typename DerivedC::Scalar,Dynamic,6> sin_theta(m,6);
sin_theta.col(0) = vol.array() / ((2./(3.*l.col(0).array())).array() * s.col(1).array() * s.col(2).array());
sin_theta.col(1) = vol.array() / ((2./(3.*l.col(1).array())).array() * s.col(2).array() * s.col(0).array());
sin_theta.col(2) = vol.array() / ((2./(3.*l.col(2).array())).array() * s.col(0).array() * s.col(1).array());
sin_theta.col(3) = vol.array() / ((2./(3.*l.col(3).array())).array() * s.col(3).array() * s.col(0).array());
sin_theta.col(4) = vol.array() / ((2./(3.*l.col(4).array())).array() * s.col(3).array() * s.col(1).array());
sin_theta.col(5) = vol.array() / ((2./(3.*l.col(5).array())).array() * s.col(3).array() * s.col(2).array());
// http://arxiv.org/pdf/1208.0354.pdf Page 18
C = (1./6.) * l.array() * cos_theta.array() / sin_theta.array();
break;
}
default:
{
fprintf(stderr,
"cotmatrix_entries.h: Error: Simplex size (%d) not supported\n", simplex_size);
assert(false);
}
}
}
#ifdef IGL_STATIC_LIBRARY
// Explicit template instantiation
// generated by autoexplicit.sh
template void igl::cotmatrix_entries<Eigen::Matrix<double, -1, -1, 1, -1, -1>, Eigen::Matrix<int, -1, -1, 0, -1, -1>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::Matrix<double, -1, -1, 1, -1, -1> > const&, Eigen::MatrixBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> > const&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&);
// generated by autoexplicit.sh
template void igl::cotmatrix_entries<Eigen::Matrix<double, -1, -1, 0, -1, -1>, Eigen::Matrix<int, -1, -1, 0, -1, -1>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> > const&, Eigen::MatrixBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> > const&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&);
// generated by autoexplicit.sh
template void igl::cotmatrix_entries<Eigen::Matrix<double, -1, 3, 0, -1, 3>, Eigen::Matrix<int, -1, 4, 0, -1, 4>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::Matrix<double, -1, 3, 0, -1, 3> > const&, Eigen::MatrixBase<Eigen::Matrix<int, -1, 4, 0, -1, 4> > const&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&);
// generated by autoexplicit.sh
template void igl::cotmatrix_entries<Eigen::Matrix<double, -1, 3, 0, -1, 3>, Eigen::Matrix<int, -1, 3, 0, -1, 3>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::Matrix<double, -1, 3, 0, -1, 3> > const&, Eigen::MatrixBase<Eigen::Matrix<int, -1, 3, 0, -1, 3> > const&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&);
#endif