70 lines
1.7 KiB
C++
70 lines
1.7 KiB
C++
#include <igl/eigs.h>
|
|
#include <igl/cotmatrix.h>
|
|
#include <igl/massmatrix.h>
|
|
#include <igl/Viewer/viewer.h>
|
|
#include <igl/parula.h>
|
|
#include <igl/read_triangle_mesh.h>
|
|
#include <Eigen/Sparse>
|
|
#include <iostream>
|
|
#include <queue>
|
|
|
|
Eigen::MatrixXd V,U;
|
|
Eigen::MatrixXi F;
|
|
int c=0;
|
|
double bbd = 1;
|
|
bool twod = 0;
|
|
int main(int argc, char * argv[])
|
|
{
|
|
using namespace Eigen;
|
|
using namespace std;
|
|
using namespace igl;
|
|
VectorXd D;
|
|
if(!read_triangle_mesh("../shared/beetle.off",V,F))
|
|
{
|
|
cout<<"failed to load mesh"<<endl;
|
|
}
|
|
twod = V.col(2).minCoeff()==V.col(2).maxCoeff();
|
|
bbd = (V.colwise().maxCoeff()-V.colwise().minCoeff()).norm();
|
|
SparseMatrix<double> L,M;
|
|
cotmatrix(V,F,L);
|
|
L = (-L).eval();
|
|
massmatrix(V,F,MASSMATRIX_TYPE_DEFAULT,M);
|
|
const size_t k = 5;
|
|
if(!eigs(L,M,k+1,EIGS_TYPE_SM,U,D))
|
|
{
|
|
cout<<"failed."<<endl;
|
|
}
|
|
U = ((U.array()-U.minCoeff())/(U.maxCoeff()-U.minCoeff())).eval();
|
|
|
|
igl::viewer::Viewer viewer;
|
|
viewer.callback_key_down = [&](igl::viewer::Viewer & viewer,unsigned char key,int)->bool
|
|
{
|
|
switch(key)
|
|
{
|
|
default:
|
|
return false;
|
|
case ' ':
|
|
{
|
|
U = U.rightCols(k).eval();
|
|
// Rescale eigen vectors for visualization
|
|
VectorXd Z =
|
|
bbd*0.5*U.col(c);
|
|
Eigen::MatrixXd C;
|
|
igl::parula(U.col(c).eval(),false,C);
|
|
c = (c+1)%U.cols();
|
|
if(twod)
|
|
{
|
|
V.col(2) = Z;
|
|
}
|
|
viewer.data.set_mesh(V,F);
|
|
viewer.data.compute_normals();
|
|
viewer.data.set_colors(C);
|
|
return true;
|
|
}
|
|
}
|
|
};
|
|
viewer.callback_key_down(viewer,' ',0);
|
|
viewer.core.show_lines = false;
|
|
viewer.launch();
|
|
}
|