OpenVDB - create_levelset_volume (usage)

gistfile1.cpp

  using GridT = openvdb::FloatGrid;
  auto grid1 = openvdb::tools::createLevelSetSphere<GridT>(
      512.0, openvdb::Vec3f(0, 0, 0), 1, 2);

  Sphere s0{glm::vec4(-512,-512,512,1), 16};
  LinearSphereSweptVolume volume0(s0, /*translation=*/glm::vec3(1024, 1024, 0));
  auto grid2 = create_levelset_volume<GridT>(volume0, 1, 2);
  openvdb::tools::csgDifference(*grid1, *grid2);

  s0 = Sphere{glm::vec4(-512,512,1024,1), 16};
  volume0 = LinearSphereSweptVolume(s0, /*translation=*/glm::vec3(1024,-1024, 0));
  grid2 = create_levelset_volume<GridT>(volume0, 2, 4);
  openvdb::tools::csgDifference(*grid1, *grid2);

  AABB volume1{vec3(-20, -20, -600), vec3(20, 20, 600)};
  grid2 = create_levelset_volume<GridT>(volume1, 1, 2);
  openvdb::tools::csgDifference(*grid1, *grid2);