CGAL users discussion list

["J. Scheurich" <>]

On 21.01.20 21:35, Sebastien Loriot (GeometryFactory) wrote:
> OFF should be replaced by COFF according to the file format (or CNOFF
> if you have normals).

If i add COFF instead of OFF in facecube.off, i still get "color do not
exist" in the test program.

https://github.com/CGAL/cgal/pull/1013

talks about Scanner_OFF.h, how to use it ?

so long
MUFTI
> > 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");
> > }