Contour Triangulation Example

Example of generating a triangulation from a contour.

• C++

  #include <MRMesh/MRImageLoad.h>
  #include <MRMesh/MRDistanceMap.h>
  #include <MRMesh/MRPolyline.h>
  #include <MRMesh/MRMesh.h>
  #include <MRMesh/MR2DContoursTriangulation.h>
  #include <MRMesh/MRMeshSave.h>
  #include <iostream>
   
  int main()
  {
      // load image as distance map
      auto imageLoadRes = MR::ImageLoad::fromAnySupportedFormat( "logo.jpg" );
      if ( !imageLoadRes.has_value() )
      {
          std::cerr << imageLoadRes.error() << "\n";
          return 1; // error while loading file
      }
      auto dmRes = MR::convertImageToDistanceMap( *imageLoadRes );
      if ( !dmRes.has_value() )
      {
          std::cerr << dmRes.error() << "\n";
          return 1; // error while converting image to distance map
      }
   
      auto pl2 = MR::distanceMapTo2DIsoPolyline( *dmRes, 210.0f );
      auto triangulationRes = MR::PlanarTriangulation::triangulateContours( pl2.contours() );
   
      auto saveRes = MR::MeshSave::toAnySupportedFormat( triangulationRes, "LogoMesh.ctm" );
      if ( !saveRes.has_value() )
      {
          std::cerr << saveRes.error() << "\n";
          return 1; // error while saving file
      }
      return 0;
  }

• Python

  from meshlib import mrmeshpy as mm
  from pathlib import Path
   
  dm = mm.loadDistanceMapFromImage("logo.jpg") # load image
  pl2 = mm.distanceMapTo2DIsoPolyline(dm, 210) # make iso lines from image
  logo_mesh = mm.PlanarTriangulation.triangulateContours(pl2.contours()) # triangulate isolines
   
  mm.saveMesh(logo_mesh, "LogoMesh.ctm")

• C

  #include <MRCMesh/MRImageLoad.h>
  #include <MRCMesh/MRDistanceMap.h>
  #include <MRCMesh/MRPolyline.h>
  #include <MRCMesh/MRMesh.h>
  #include <MRCMesh/MR2DContoursTriangulation.h>
  #include <MRCMesh/MRMeshSave.h>
  #include <MRCMisc/expected_MR_Mesh_std_string.h>
  #include <MRCMisc/expected_MR_Image_std_string.h>
  #include <MRCMisc/expected_MR_DistanceMap_std_string.h>
  #include <MRCMisc/expected_void_std_string.h>
  #include <MRCMisc/std_vector_std_vector_MR_Vector2f.h>
  #include <MRCMisc/std_string.h>
   
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
   
  int main( void )
  {
      int rc = EXIT_FAILURE;
      // load image as distance map
      MR_expected_MR_Image_std_string* imageLoadRes = MR_ImageLoad_fromAnySupportedFormat( "logo.jpg", NULL );
      MR_Image* image = MR_expected_MR_Image_std_string_GetMutableValue( imageLoadRes );
      if ( !image )
      {
          fprintf( stderr, "Failed to load image: %s\n", MR_std_string_Data( MR_expected_MR_Image_std_string_GetError( imageLoadRes ) ) );
          goto fail_load; // error while loading file
      }
   
      MR_expected_MR_DistanceMap_std_string* dmRes = MR_convertImageToDistanceMap( image, NULL, NULL );
      MR_DistanceMap* dm = MR_expected_MR_DistanceMap_std_string_GetMutableValue( dmRes );
      if ( !dm )
      {
          fprintf( stderr, "Failed to convert image to distance map: %s\n", MR_std_string_Data( MR_expected_MR_DistanceMap_std_string_GetError( dmRes ) ) );
          goto fail_conversion; // error while converting image to distance map
      }
   
      MR_Polyline2* pl2 = MR_distanceMapTo2DIsoPolyline_2( dm, 210.0f );
      MR_std_vector_std_vector_MR_Vector2f* conts = MR_Polyline2_contours( pl2, NULL );
   
      MR_Mesh* triangulationRes = MR_PlanarTriangulation_triangulateContours_std_vector_std_vector_MR_Vector2f( conts, NULL );
   
      MR_expected_void_std_string* saveEx = MR_MeshSave_toAnySupportedFormat_3( triangulationRes, "LogoMesh.ctm", NULL, NULL );
      if ( MR_expected_void_std_string_GetError( saveEx ) )
      {
          fprintf( stderr, "Failed to save mesh: %s\n", MR_std_string_Data( MR_expected_void_std_string_GetError( saveEx ) ) );
          goto fail_save; // error while saving file
      }
   
      rc = EXIT_SUCCESS;
  fail_save:
      MR_expected_void_std_string_Destroy( saveEx );
   
      MR_Mesh_Destroy( triangulationRes );
      MR_std_vector_std_vector_MR_Vector2f_Destroy( conts );
      MR_Polyline2_Destroy( pl2 );
  fail_conversion:
      MR_expected_MR_DistanceMap_std_string_Destroy( dmRes );
  fail_load:
      MR_expected_MR_Image_std_string_Destroy( imageLoadRes );
      return rc;
  }