Skip to content

LOxGrid

vtk-examples/Cxx/VisualizationAlgorithms/LOxGrid


Desription

Portion of computational grid for the LOx post.

Other languages

See (Python)

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

LOxGrid.cxx

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkLookupTable.h>
#include <vtkMultiBlockDataSet.h>
#include <vtkMultiBlockPLOT3DReader.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPointSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkStreamTracer.h>
#include <vtkStructuredGrid.h>
#include <vtkStructuredGridGeometryFilter.h>
#include <vtkStructuredGridOutlineFilter.h>
#include <vtkTubeFilter.h>

//// LOx post CFD case study

int main(int argc, char* argv[])
{
  if (argc < 3)
  {
    std::cout << "Usage: " << argv[0] << " postxyz.bin postq.bin" << std::endl;
    return EXIT_FAILURE;
  }
  // read data
  //
  vtkNew<vtkMultiBlockPLOT3DReader> pl3d;
  pl3d->AutoDetectFormatOn();
  pl3d->SetXYZFileName(argv[1]);
  pl3d->SetQFileName(argv[2]);
  pl3d->SetScalarFunctionNumber(153);
  pl3d->SetVectorFunctionNumber(200);
  pl3d->Update();

  vtkStructuredGrid* sg =
      dynamic_cast<vtkStructuredGrid*>(pl3d->GetOutput()->GetBlock(0));

  vtkNew<vtkNamedColors> colors;

  // blue to red lut
  //
  vtkNew<vtkLookupTable> lut;
  lut->SetHueRange(0.667, 0.0);

  // computational planes
  vtkNew<vtkStructuredGridGeometryFilter> floorComp;
  floorComp->SetExtent(0, 37, 0, 75, 0, 0);
  floorComp->SetInputData(sg);
  floorComp->Update();

  vtkNew<vtkPolyDataMapper> floorMapper;
  floorMapper->SetInputConnection(floorComp->GetOutputPort());
  floorMapper->ScalarVisibilityOff();
  floorMapper->SetLookupTable(lut);

  vtkNew<vtkActor> floorActor;
  floorActor->SetMapper(floorMapper);
  floorActor->GetProperty()->SetRepresentationToWireframe();
  floorActor->GetProperty()->SetColor(colors->GetColor3d("Beige").GetData());
  floorActor->GetProperty()->SetLineWidth(2);

  vtkNew<vtkStructuredGridGeometryFilter> subFloorComp;

  subFloorComp->SetExtent(0, 37, 0, 15, 22, 22);
  subFloorComp->SetInputData(sg);

  vtkNew<vtkPolyDataMapper> subFloorMapper;
  subFloorMapper->SetInputConnection(subFloorComp->GetOutputPort());
  subFloorMapper->SetLookupTable(lut);
  subFloorMapper->SetScalarRange(sg->GetScalarRange());

  vtkNew<vtkActor> subFloorActor;

  subFloorActor->SetMapper(subFloorMapper);

  vtkNew<vtkStructuredGridGeometryFilter> subFloor2Comp;
  subFloor2Comp->SetExtent(0, 37, 60, 75, 22, 22);
  subFloor2Comp->SetInputData(sg);

  vtkNew<vtkPolyDataMapper> subFloor2Mapper;
  subFloor2Mapper->SetInputConnection(subFloor2Comp->GetOutputPort());
  subFloor2Mapper->SetLookupTable(lut);
  subFloor2Mapper->SetScalarRange(sg->GetScalarRange());

  vtkNew<vtkActor> subFloor2Actor;

  subFloor2Actor->SetMapper(subFloor2Mapper);

  vtkNew<vtkStructuredGridGeometryFilter> postComp;

  postComp->SetExtent(10, 10, 0, 75, 0, 37);
  postComp->SetInputData(sg);

  vtkNew<vtkPolyDataMapper> postMapper;
  postMapper->SetInputConnection(postComp->GetOutputPort());
  postMapper->SetLookupTable(lut);
  postMapper->SetScalarRange(sg->GetScalarRange());

  vtkNew<vtkActor> postActor;
  postActor->SetMapper(postMapper);
  postActor->GetProperty()->SetColor(colors->GetColor3d("Beige").GetData());

  vtkNew<vtkStructuredGridGeometryFilter> fanComp;
  fanComp->SetExtent(0, 37, 38, 38, 0, 37);
  fanComp->SetInputData(sg);

  vtkNew<vtkPolyDataMapper> fanMapper;
  fanMapper->SetInputConnection(fanComp->GetOutputPort());
  fanMapper->SetLookupTable(lut);
  fanMapper->SetScalarRange(sg->GetScalarRange());

  vtkNew<vtkActor> fanActor;

  fanActor->SetMapper(fanMapper);
  fanActor->GetProperty()->SetColor(colors->GetColor3d("Beige").GetData());

  // streamers
  //
  // spherical seed points
  vtkNew<vtkPointSource> rake;
  rake->SetCenter(-0.74, 0, 0.3);
  rake->SetNumberOfPoints(10);

  // a line of seed points
  vtkNew<vtkStructuredGridGeometryFilter> seedsComp;
  seedsComp->SetExtent(10, 10, 37, 39, 1, 35);
  seedsComp->SetInputData(sg);

  vtkNew<vtkStreamTracer> streamers;
  streamers->SetInputConnection(pl3d->GetOutputPort());

  //    streamers SetSource [rake GetOutput]
  streamers->SetSourceConnection(seedsComp->GetOutputPort());
  streamers->SetMaximumPropagation(250);
  streamers->SetInitialIntegrationStep(.2);
  streamers->SetMinimumIntegrationStep(.01);
  streamers->SetIntegratorType(2);
  streamers->Update();

  vtkNew<vtkTubeFilter> tubes;
  tubes->SetInputConnection(streamers->GetOutputPort());
  tubes->SetNumberOfSides(8);
  tubes->SetRadius(0.08);
  tubes->SetVaryRadius(0);

  vtkNew<vtkPolyDataMapper> mapTubes;

  mapTubes->SetInputConnection(tubes->GetOutputPort());
  mapTubes->SetScalarRange(sg->GetScalarRange());

  vtkNew<vtkActor> tubesActor;
  tubesActor->SetMapper(mapTubes);

  // outline
  vtkNew<vtkStructuredGridOutlineFilter> outline;
  outline->SetInputData(sg);

  vtkNew<vtkPolyDataMapper> outlineMapper;
  outlineMapper->SetInputConnection(outline->GetOutputPort());

  vtkNew<vtkActor> outlineActor;
  outlineActor->SetMapper(outlineMapper);
  outlineActor->GetProperty()->SetColor(colors->GetColor3d("Beige").GetData());

  // Create graphics stuff
  vtkNew<vtkRenderer> ren1;
  vtkNew<vtkRenderWindow> renWin;
  renWin->AddRenderer(ren1);

  vtkNew<vtkRenderWindowInteractor> iren;
  iren->SetRenderWindow(renWin);

  // Add the actors to the renderer, set the background and size
  //
  ren1->AddActor(outlineActor);
  ren1->AddActor(floorActor);
  ren1->AddActor(subFloorActor);
  ren1->AddActor(subFloor2Actor);
  ren1->AddActor(postActor);
  ren1->AddActor(fanActor);
  ren1->AddActor(tubesActor);

  vtkNew<vtkCamera> aCam;
  aCam->SetFocalPoint(0.00657892, 0, 2.41026);
  aCam->SetPosition(-1.94838, -47.1275, 39.4607);
  aCam->SetViewUp(0.00653193, 0.617865, 0.786257);
  ren1->ResetCamera();
  aCam->Dolly(1.);
  aCam->SetClippingRange(1, 100);

  ren1->SetBackground(colors->GetColor3d("SlateGray").GetData());
  ren1->SetActiveCamera(aCam);
  renWin->SetSize(640, 480);
  renWin->SetWindowName("LOxGrid");

  renWin->Render();
  iren->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(LOxGrid)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersCore
  vtkFiltersFlowPaths
  vtkFiltersGeometry
  vtkFiltersSources
  vtkIOParallel
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping LOxGrid: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(LOxGrid MACOSX_BUNDLE LOxGrid.cxx )
  target_link_libraries(LOxGrid PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(LOxGrid MACOSX_BUNDLE LOxGrid.cxx )
  target_link_libraries(LOxGrid PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS LOxGrid
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build LOxGrid

Click here to download LOxGrid and its CMakeLists.txt file. Once the tarball LOxGrid.tar has been downloaded and extracted,

cd LOxGrid/build

If VTK is installed:

cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

Build the project:

make

and run it:

./LOxGrid

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.