app_compute_signature.cc

This is an application example of the compute_gwzsig function usage and SignatureMeshT class.

See also:

zsig.hh

#include <zsig.hh>

#define DOMAIN_GRID_X 16
#define DOMAIN_GRID_Y 16
#define VALUE_TYPE long double

typedef zsig::SignatureMeshT< VALUE_TYPE > mesh_type;

typedef mesh_type::bbox_type bbox_type;

#define ZERNIKE_ORDER 8

typedef zsig::ZernikePolynomialsBasisT< ZERNIKE_ORDER, VALUE_TYPE > zpolbasis_type;

// Main
int main( int argc, char *argv[] ) {

        std::cout << "[zsig] Usage: " << argv[0] << " read.off write.sig\n";

        if( argc != 3 ) return 1;

        std::cout << "[zsig] Application 1 :: Computing Vertex Signatures\n";

        std::cout << "[zsig] Reading mesh: " << argv[1] << "\n";

        mesh_type mesh;

        mesh.read_off( argv[1] );

        std::cout << "[zsig] Building mesh additional information\n";

        mesh.build_bbox();

        mesh.build_neighborhood();

        mesh.build_fnormals();

        mesh.build_grid();

        bbox_type bb = mesh.bounding_box();

        std::cout << "[zsig] Mesh information:\n";

        std::cout << "[zsig] Mesh has " << mesh.size_of_vertices() << " vertices\n";
        std::cout << "[zsig] Mesh has " << mesh.size_of_faces() << " faces\n";
        std::cout << "[zsig] Mesh grid is " << mesh.grid_dimension() << " ^3 (grid dimension)\n";
        std::cout << "[zsig] Mesh's bounding box is [" << bb[0] << " : " << bb[1] << "]\n";
        std::cout << "[zsig] Mesh's diagonal distance is " << mesh.diagonal_distance() << "\n";

        std::cout << "[zsig] Computing Gaussian-weighted Zernike-based signatures\n";

        std::vector< zpolbasis_type > gwzsig;

        zsig::compute_gwzsig< ZERNIKE_ORDER, VALUE_TYPE, DOMAIN_GRID_X, DOMAIN_GRID_Y >( gwzsig, mesh );

        std::cout << "[zsig] Writing signature file: " << argv[2] << "\n";

        std::ofstream out( argv[2] );

        // signature file example header
        out << mesh.size_of_vertices() << " " // number of signatures
            << mesh.maximum_search_distance() << " " // signature plane radius
            << DOMAIN_GRID_X << " " // number of rows in signature
            << DOMAIN_GRID_Y << " " // number of columns in signature
            << ZERNIKE_ORDER << " " // zernike polynomial order
            << sizeof(VALUE_TYPE) // value type size in bytes
            << "\n";

        for (unsigned vid = 0; vid < mesh.size_of_vertices(); ++vid)
                out << gwzsig[vid] << "\n";

        out.close();

        std::cout << "[zsig] Done!\n";

        return 0;

}