Mesh extrude

Example of extrude faces on mesh

• C++

  #include <MRMesh/MRBitSet.h>
  #include <MRMesh/MRBitSetParallelFor.h>
  #include <MRMesh/MRId.h>
  #include <MRMesh/MRMesh.h>
  #include <MRMesh/MRMeshExtrude.h>
  #include <MRMesh/MRMeshLoad.h>
  #include <MRMesh/MRMeshSave.h>
  #include <MRMesh/MRRegionBoundary.h>
   
  #include <iostream>
   
  int main()
  {
      // Load mesh
      auto loadRes = MR::MeshLoad::fromAnySupportedFormat( "mesh.stl" );
      if ( !loadRes.has_value() )
      {
          std::cerr << loadRes.error() << std::endl;
          return 1;
      }
      MR::Mesh& mesh = *loadRes;
   
      // Select faces to extrude
      MR::FaceBitSet facesToExtrude;
      facesToExtrude.autoResizeSet( MR::FaceId( 1 ) );
      facesToExtrude.autoResizeSet( MR::FaceId( 2 ) );
   
      // Create duplicated verts on region boundary
      MR::makeDegenerateBandAroundRegion( mesh, facesToExtrude );
   
      // Find vertices that will be moved
      auto vertsForMove = MR::getIncidentVerts( mesh.topology, facesToExtrude );
   
      MR::BitSetParallelFor( vertsForMove, [&] ( MR::VertId v )
      {
          // Move each vertex
          mesh.points[v] += MR::Vector3f::plusZ();
      } );
   
      // Invalidate internal caches after manual changing
      mesh.invalidateCaches();
   
      // Save mesh
      if ( auto saveRes = MR::MeshSave::toAnySupportedFormat( mesh, "extrudedMesh.stl" ); !saveRes )
      {
          std::cerr << saveRes.error() << std::endl;
          return 1;
      }
  }

• Python

  import meshlib.mrmeshpy as mrmeshpy
   
  # Load mesh
  mesh = mrmeshpy.loadMesh("mesh.stl")
   
  # Prepare region to extrude
  faces_to_extrude = mrmeshpy.FaceBitSet()
  faces_to_extrude.resize(3, False)
  faces_to_extrude.set(mrmeshpy.FaceId(1), True)
  faces_to_extrude.set(mrmeshpy.FaceId(2), True)
   
  # Create duplicated verts on region boundary
  mrmeshpy.makeDegenerateBandAroundRegion(mesh, faces_to_extrude)
   
  # Find vertices that will be moved
  verts_for_move = mrmeshpy.getIncidentVerts(mesh.topology, faces_to_extrude)
   
  # Move each vertex
  for v in range(verts_for_move.size()):
      if verts_for_move.test(mrmeshpy.VertId(v)):
          mesh.points.vec[v] += mrmeshpy.Vector3f(0.0, 0.0, 1.0)
   
  # Invalidate internal caches after manual changing
  mesh.invalidateCaches()
   
  # Save mesh
  mrmeshpy.saveMesh(mesh, "extrudedMesh.stl")

• C

  #include <MRMeshC/MRBitSet.h>
  #include <MRMeshC/MRMesh.h>
  #include <MRMeshC/MRMeshExtrude.h>
  #include <MRMeshC/MRMeshLoad.h>
  #include <MRMeshC/MRMeshSave.h>
  #include <MRMeshC/MRRegionBoundary.h>
   
  #include <stdlib.h>
   
  int main( int argc, char* argv[] )
  {
      // Load mesh
      MRMesh* mesh = mrMeshLoadFromAnySupportedFormat( "mesh.stl", NULL );
   
      // Select faces to extrude
      MRFaceBitSet* facesToExtrude = mrFaceBitSetNew( 0, false );
      mrBitSetAutoResizeSet( (MRBitSet*)facesToExtrude, 1, true );
      mrBitSetAutoResizeSet( (MRBitSet*)facesToExtrude, 2, true );
   
      // Create duplicated verts on region boundary
      mrMakeDegenerateBandAroundRegion( mesh, facesToExtrude );
   
      // Find vertices that will be moved
      MRVertBitSet* vertsToMove = mrGetIncidentVertsFromFaces( mrMeshTopology( mesh ), facesToExtrude );
      MRVector3f* points = mrMeshPointsRef( mesh );
      MRVector3f shift = mrVector3fPlusZ();
      for ( int i = 0; i < mrMeshPointsNum( mesh ); ++i )
          if ( mrBitSetTest( (MRBitSet*)vertsToMove, i ) )
              points[i] = mrVector3fAdd( &points[i], &shift );
   
      // Invalidate internal caches after manual changing
      mrMeshInvalidateCaches( mesh, true );
   
      // Save mesh
      mrMeshSaveToAnySupportedFormat( mesh, "extrudedMesh.stl", NULL, NULL );
   
      mrVertBitSetFree( vertsToMove );
      mrFaceBitSetFree( facesToExtrude );
      mrMeshFree( mesh );
      return EXIT_SUCCESS;
  }