File size: 2,485 Bytes
5b89cb9 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 | #include <igl/boundary_facets.h>
#include <igl/cotmatrix.h>
#include <igl/invert_diag.h>
#include <igl/jet.h>
#include <igl/massmatrix.h>
#include <igl/min_quad_with_fixed.h>
#include <igl/readOFF.h>
#include <igl/opengl/glfw/Viewer.h>
#include <Eigen/Sparse>
#include <iostream>
int main(int argc, char *argv[])
{
using namespace Eigen;
using namespace std;
MatrixXd V;
MatrixXi F;
igl::readOFF(TUTORIAL_SHARED_PATH "/cheburashka.off",V,F);
// Two fixed points
VectorXi b(2,1);
// Left hand, left foot
b<<4331,5957;
VectorXd bc(2,1);
bc<<1,-1;
// Construct Laplacian and mass matrix
SparseMatrix<double> L,M,Minv,Q;
igl::cotmatrix(V,F,L);
igl::massmatrix(V,F,igl::MASSMATRIX_TYPE_VORONOI,M);
igl::invert_diag(M,Minv);
// Bi-Laplacian
Q = L * (Minv * L);
// Zero linear term
VectorXd B = VectorXd::Zero(V.rows(),1);
VectorXd Z,Z_const;
{
// Alternative, short hand
igl::min_quad_with_fixed_data<double> mqwf;
// Empty constraints
VectorXd Beq;
SparseMatrix<double> Aeq;
igl::min_quad_with_fixed_precompute(Q,b,Aeq,true,mqwf);
igl::min_quad_with_fixed_solve(mqwf,B,bc,Beq,Z);
}
{
igl::min_quad_with_fixed_data<double> mqwf;
// Constraint forcing difference of two points to be 0
SparseMatrix<double> Aeq(1,V.rows());
// Right hand, right foot
Aeq.insert(0,6074) = 1;
Aeq.insert(0,6523) = -1;
Aeq.makeCompressed();
VectorXd Beq(1,1);
Beq(0) = 0;
igl::min_quad_with_fixed_precompute(Q,b,Aeq,true,mqwf);
igl::min_quad_with_fixed_solve(mqwf,B,bc,Beq,Z_const);
}
// Use same color axes
const double min_z = std::min(Z.minCoeff(),Z_const.minCoeff());
const double max_z = std::max(Z.maxCoeff(),Z_const.maxCoeff());
// Plot the mesh with pseudocolors
igl::opengl::glfw::Viewer viewer;
viewer.data().set_mesh(V, F);
viewer.data().show_lines = false;
viewer.data().set_data(Z,min_z,max_z);
viewer.callback_key_down =
[&Z,&Z_const,&min_z,&max_z](igl::opengl::glfw::Viewer& viewer,unsigned char key,int mod)->bool
{
if(key == ' ')
{
static bool toggle = true;
viewer.data().set_data(toggle?Z_const:Z,min_z,max_z);
toggle = !toggle;
return true;
}else
{
return false;
}
};
cout<<
"Press [space] to toggle between unconstrained and constrained."<<endl;
viewer.launch();
}
|