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>
   
  int main()
  {
      // Load mesh
      auto mesh = MR::MeshLoad::fromAnySupportedFormat( "mesh.stl" );
      assert( mesh );
   
      // Compute mesh bounding box
      const auto box = mesh->computeBoundingBox();
   
      // Construct deformer on mesh vertices
      MR::FreeFormDeformer ffDeformer( mesh->points, mesh->topology.getValidVerts() );
   
      // 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
      MR::MeshSave::toAnySupportedFormat( *mesh, "deformed_mesh.stl" );
  }

• 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 <MRMeshC/MRFreeFormDeformer.h>
  #include <MRMeshC/MRMesh.h>
  #include <MRMeshC/MRMeshLoad.h>
  #include <MRMeshC/MRMeshSave.h>
   
  #include <stdlib.h>
   
  int main( int argc, char* argv[] )
  {
      // Load mesh
      MRMesh* mesh = mrMeshLoadFromAnySupportedFormat( "mesh.stl", NULL );
   
      // Compute mesh bounding box
      MRBox3f box = mrMeshComputeBoundingBox( mesh, NULL );
   
      // Construct deformer on mesh vertices
      MRFreeFormDeformer* ffDeformer = mrFreeFormDeformerNewFromMesh( mesh, NULL );
   
      // Init deformer with 3x3 grid on mesh box
      MRVector3i resolution = mrVector3iDiagonal( 3 );
      mrFreeFormDeformerInit( ffDeformer, &resolution, &box );
   
      // Move some control points of the grid to the center
      MRVector3i controlPoints[] = {
          { 1, 1, 0 },
          { 1, 1, 2 },
          { 0, 1, 1 },
          { 2, 1, 1 },
          { 1, 0, 1 },
          { 1, 2, 1 },
      };
      MRVector3f center = mrBox3fCenter( &box );
      for ( int i = 0; i < 6; ++i )
          mrFreeFormDeformerSetRefGridPointPosition( ffDeformer, &controlPoints[i], &center );
   
      // Apply the deformation to the mesh vertices
      mrFreeFormDeformerApply( ffDeformer );
   
      // Invalidate the mesh because of external vertex changes
      mrMeshInvalidateCaches( mesh, true );
   
      // Save deformed mesh
      mrMeshSaveToAnySupportedFormat( mesh, "deformed_mesh.stl", NULL, NULL );
   
      mrFreeFormDeformerFree( ffDeformer );
      mrMeshFree( mesh );
      return EXIT_SUCCESS;
  }