Free Form Deformation Example

Example of using Free Form deformation of the mesh

• C++

  #include <MRMesh/MRFreeFormDeformer.h>
  #include <MRMesh/MRMesh.h>
  #include <MRMesh/MRMeshLoad.h>
  #include <MRMesh/MRMeshSave.h>
   
  #include <iostream>
   
  int main()
  {
      // Load mesh
      auto mesh = MR::MeshLoad::fromAnySupportedFormat( "mesh.stl" );
      if ( !mesh.has_value() )
      {
          std::cerr << mesh.error() << std::endl;
          return 1;
      }
   
      // Construct deformer on mesh vertices
      MR::FreeFormDeformer ffDeformer( mesh->points, mesh->topology.getValidVerts() );
   
      // Compute mesh bounding box
      const auto box = mesh->computeBoundingBox();
   
      // Init deformer with 3x3 grid on mesh box
      ffDeformer.init( MR::Vector3i::diagonal( 3 ), box );
   
      // Move some control points of the grid to the center
      ffDeformer.setRefGridPointPosition( { 1, 1, 0 }, box.center() );
      ffDeformer.setRefGridPointPosition( { 1, 1, 2 }, box.center() );
      ffDeformer.setRefGridPointPosition( { 0, 1, 1 }, box.center() );
      ffDeformer.setRefGridPointPosition( { 2, 1, 1 }, box.center() );
      ffDeformer.setRefGridPointPosition( { 1, 0, 1 }, box.center() );
      ffDeformer.setRefGridPointPosition( { 1, 2, 1 }, box.center() );
   
      // Apply the deformation to the mesh vertices
      ffDeformer.apply();
   
      // Invalidate the mesh because of external vertex changes
      mesh->invalidateCaches();
   
      // Save deformed mesh
      if ( auto saveRes = MR::MeshSave::toAnySupportedFormat( *mesh, "deformed_mesh.stl" ); !saveRes )
      {
          std::cerr << saveRes.error() << std::endl;
          return 1;
      }
  }

• Python

  Note

  Python API version 3 and later

  from meshlib import mrmeshpy as mm
   
  # Load mesh
  mesh = mm.loadMesh("mesh.stl")
   
  # Compute mesh bounding box
  box = mesh.computeBoundingBox()
   
  # Construct deformer on mesh vertices
  ffDeformer = mm.FreeFormDeformer(mesh.points,mesh.topology.getValidVerts())
   
  # Init deformer with 3x3 grid on mesh box
  ffDeformer.init(mm.Vector3i.diagonal(3),box)
   
  # Move some control points of grid to the center
  ffDeformer.setRefGridPointPosition(mm.Vector3i(1,1,0),box.center())
  ffDeformer.setRefGridPointPosition(mm.Vector3i(1,1,2),box.center())
  ffDeformer.setRefGridPointPosition(mm.Vector3i(0,1,1),box.center())
  ffDeformer.setRefGridPointPosition(mm.Vector3i(2,1,1),box.center())
  ffDeformer.setRefGridPointPosition(mm.Vector3i(1,0,1),box.center())
  ffDeformer.setRefGridPointPosition(mm.Vector3i(1,2,1),box.center())
   
  # Apply deformation to mesh vertices
  ffDeformer.apply()
   
  # Invalidate mesh because of external vertices changes
  mesh.invalidateCaches()
   
  # Save deformed mesh
  mm.saveMesh(mesh,"deformed_mesh.stl")

• C

  #include <MRCMesh/MRFreeFormDeformer.h>
  #include <MRCMesh/MRMesh.h>
  #include <MRCMesh/MRMeshLoad.h>
  #include <MRCMesh/MRMeshSave.h>
  #include <MRCMisc/expected_MR_Mesh_std_string.h>
  #include <MRCMisc/std_string.h>
   
  #include <stdio.h>
  #include <stdlib.h>
   
  int main( void )
  {
      // Load mesh
      MR_expected_MR_Mesh_std_string* meshEx = MR_MeshLoad_fromAnySupportedFormat_2( "mesh.stl", NULL, NULL );
      MR_Mesh* mesh = MR_expected_MR_Mesh_std_string_GetMutableValue( meshEx );
   
      // Handle failure to load mesh
      if ( !mesh )
      {
          fprintf( stderr, "Failed to load mesh: %s\n", MR_std_string_Data( MR_expected_MR_Mesh_std_string_GetError( meshEx ) ) );
          MR_expected_MR_Mesh_std_string_Destroy( meshEx );
          return 1;
      }
   
      // Compute mesh bounding box
      MR_Box3f box = MR_Mesh_computeBoundingBox_1( mesh, NULL );
   
      // Construct deformer on mesh vertices
      MR_FreeFormDeformer* ffDeformer = MR_FreeFormDeformer_Construct_MR_Mesh( mesh, NULL );
   
      // Init deformer with 3x3 grid on mesh box
      MR_Vector3i resolution = MR_Vector3i_diagonal( 3 );
      MR_FreeFormDeformer_init( ffDeformer, &resolution, &box );
   
      // Move some control points of the grid to the center
      MR_Vector3i controlPoints[] = {
          { 1, 1, 0 },
          { 1, 1, 2 },
          { 0, 1, 1 },
          { 2, 1, 1 },
          { 1, 0, 1 },
          { 1, 2, 1 },
      };
      MR_Vector3f center = MR_Box3f_center( &box );
      for ( int i = 0; i < 6; ++i )
          MR_FreeFormDeformer_setRefGridPointPosition( ffDeformer, &controlPoints[i], &center );
   
      // Apply the deformation to the mesh vertices
      MR_FreeFormDeformer_apply( ffDeformer );
   
      // Invalidate the mesh because of external vertex changes
      MR_Mesh_invalidateCaches( mesh, NULL );
   
      // Save deformed mesh
      MR_MeshSave_toAnySupportedFormat_3( mesh, "deformed_mesh.stl", NULL, NULL );
   
      MR_FreeFormDeformer_Destroy( ffDeformer );
      MR_expected_MR_Mesh_std_string_Destroy( meshEx );
      return EXIT_SUCCESS;
  }

• C#

  public class FreeFormDeformationExample
  {
      public static void Run(string[] args)
      {
          try
          {
              // Load mesh
              var mesh = MR.MeshLoad.FromAnySupportedFormat("mesh.stl");
   
              // Compute mesh bounding box
              MR.Box3f box = mesh.GetBoundingBox();
   
              // Construct deformer on mesh vertices
              MR.FreeFormDeformer ffDeformer = new(mesh);
   
              // Init deformer with 3x3 grid on mesh box
              ffDeformer.Init(MR.Vector3i.Diagonal(3), box);
   
              // Move some control points of the grid to the center
              ffDeformer.SetRefGridPointPosition(new MR.Vector3i(1, 1, 0), box.Center());
              ffDeformer.SetRefGridPointPosition(new MR.Vector3i(1, 1, 2), box.Center());
              ffDeformer.SetRefGridPointPosition(new MR.Vector3i(0, 1, 1), box.Center());
              ffDeformer.SetRefGridPointPosition(new MR.Vector3i(2, 1, 1), box.Center());
              ffDeformer.SetRefGridPointPosition(new MR.Vector3i(1, 0, 1), box.Center());
              ffDeformer.SetRefGridPointPosition(new MR.Vector3i(1, 2, 1), box.Center());
   
              // Apply the deformation to the mesh vertices
              ffDeformer.Apply();
   
              // Invalidate the mesh because of external vertex changes
              mesh.InvalidateCaches();
   
              // Save deformed mesh
              MR.MeshSave.ToAnySupportedFormat(mesh, "deformed_mesh.stl");
          }
          catch (Exception e)
          {
              Console.WriteLine("Error: {0}", e.Message);
          }
      }
  }