CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

OFF should be replaced by COFF according to the file format (or CNOFF if 
you have normals).

Sebastien.



On 1/20/20 11:51 AM, J. Scheurich wrote:
> Hi,
>
> How to read .OFF file color information via CGaL ?
>
> I wrote the following test program accoording to
>
> https://stackoverflow.com/questions/55955579/cgal-how-can-i-access-vertex-colors-after-loading-an-off-file 
>
>
> $ cat readoff.cpp
>
>
> // compile:   g++ -g -O0 readoff.cpp -lCGAL
> // test data: https://people.sc.fsu.edu/~jburkardt/data/off/facecube.off
> // output:
> // $ ./a.out
> // facecube.off: Success
> // color do not exist
>
> #include <CGAL/Simple_cartesian.h>
> typedef CGAL::Simple_cartesian<double> Kernel;
> #include <CGAL/Exact_predicates_exact_constructions_kernel.h>
> #include <CGAL/Surface_mesh.h>
> #include <CGAL/Polygon_mesh_processing/corefinement.h>
> #include <CGAL/Polygon_mesh_processing/self_intersections.h>
> #include <CGAL/Polygon_mesh_processing/triangulate_faces.h>
> #include <CGAL/boost/graph/dijkstra_shortest_paths.h>
> #include <CGAL/exceptions.h>
> #include <CGAL/IO/Color.h>
> #include <boost/graph/prim_minimum_spanning_tree.hpp>
> #include <boost/foreach.hpp>
> typedef Kernel::Point_3 Point;
> typedef CGAL::Surface_mesh<Point> Surface;
> typedef CGAL::Surface_mesh<Point> SurfaceMesh;
> typedef CGAL::Color Color;
> typedef Surface::Vertex_index vertex_index;
> typedef boost::graph_traits<Surface>::vertex_descriptor vertex_descriptor;
> typedef boost::graph_traits<Surface>::face_descriptor face_descriptor;
> typedef boost::graph_traits<Surface>::halfedge_descriptor
> halfedge_descriptor;
> std::vector<Point> verts;
> std::vector<Color> cols;
>
> int main(int argc, char **argv)
> {
>      const char *filename = "facecube.off";
>      std::ifstream input(filename);
>      SurfaceMesh *mesh = new SurfaceMesh();
>
>      if (!input || !(input >> *mesh)) {
>          perror(filename);
>      }
>
>      SurfaceMesh::Property_map<SurfaceMesh::Vertex_index, CGAL::Color>
> vcolors =
>          mesh->property_map<SurfaceMesh::Vertex_index, CGAL::Color >
>          ("v:color").first;
>
>      bool colorExists = mesh->property_map
>          <SurfaceMesh::Vertex_index, CGAL::Color>("v:color").second;
>      if (colorExists )
>          printf("color exists\n");
>      else
>          printf("color do not exist\n");
> }
>
> What is the problem ?
>
>
> so long
>
> MUFTI