Files
igl/examples/marching_cubes/example.cpp
T
2012-05-07 16:48:12 +00:00

74 lines
2.2 KiB
C++

#include <igl/marching_cubes.h>
#include <iostream>
#include <cstdio>
#include "igl/MCTables.hh"
typedef float ScalarType;
typedef unsigned IndexType;
int main(int argc, char * argv[])
{
Eigen::Matrix<ScalarType, 1, 3> bb_min, bb_max;
bb_min<<0.,0.,0.;
bb_max<<1.,1.,1.;
//diagonal
Eigen::Matrix<ScalarType, 1, 3> diff = bb_max - bb_min;
//center of the sphere
Eigen::Matrix<ScalarType, 1, 3> center = 0.5 * (bb_min + bb_max);
IndexType xres, yres, zres;
xres = yres = zres = 10;
ScalarType radius = 0.42;
//steps in x,y,z direction
ScalarType dx = diff[0] / (ScalarType)(xres-1);
ScalarType dy = diff[1] / (ScalarType)(yres-1);
ScalarType dz = diff[2] / (ScalarType)(zres-1);
Eigen::Matrix<ScalarType, Eigen::Dynamic, 3> points(xres*yres*zres,3);
Eigen::Matrix<ScalarType, Eigen::Dynamic, 1> values(xres*yres*zres,1);
Eigen::Matrix<ScalarType, Eigen::Dynamic, 3> vertices;
Eigen::Matrix<IndexType, Eigen::Dynamic, 3> faces;
std::cerr<<"Sphere -- construct grid"<<std::endl;
for (unsigned int x=0; x<xres; ++x)
for (unsigned int y=0; y<yres; ++y)
for (unsigned int z=0; z<zres; ++z)
{
int index = x + y*xres + z*xres*yres;
points.row(index) = bb_min +
ScalarType(x)*Eigen::Matrix<ScalarType, 1, 3>(dx,0.,0.) +
ScalarType(y)*Eigen::Matrix<ScalarType, 1, 3>(0.,dy,0.) +
ScalarType(z)*Eigen::Matrix<ScalarType, 1, 3>(0.,0.,dz);
values[index] = (points.row(index) - center).squaredNorm() - radius*radius;
}
std::cerr<<"Sphere -- marching cubes"<<std::endl;
igl::marching_cubes(values,
points,
xres,
yres,
zres,
vertices,
faces);
std::cerr<<"Sphere -- saving"<<std::endl;
FILE * fid = fopen("sphere.obj","w");
for (unsigned i = 0; i<vertices.rows(); ++i)
fprintf(fid,"v %.10g %.10g %.10g\n",vertices(i,0),vertices(i,1),vertices(i,2));
for (unsigned i = 0; i<faces.rows(); ++i)
fprintf(fid,"f %d %d %d\n",faces(i,0)+1,faces(i,1)+1,faces(i,2)+1);
fclose(fid);
std::cerr<<"Sphere -- done."<<std::endl;
return 0;
}