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FireFlow

vtk-examples/Cxx/VisualizationAlgorithms/FireFlow

Description

The example illustrates how to combine a geometric description of a scene with a fluid flow solution. The vtkVRMLImporter read the geometry file which is a .wrl file. The file contains 32 actors. The vtkXMLUnstructuredGridReader reads the solution.

vtkStreamTracer generates streamline seeds with points generated by vtkPointSource. vtkContourFilter generates an isosurface of the velocity. A vtkSphereSource shows the sphere used in the vtkPointSource filter.

For an interactive version of this example, see FireFlowDemo.

Cite

The solution and geometry data is from the Mayavi project. Mayavi is a python application that provides an easy to use interface to many vtk filters. Both a command-line and GUI interface are provided. If you use the Mayavi data or the Mayavi application, please use the following citation in any published work: Ramachandran, P. and Varoquaux, G., Mayavi: 3D Visualization of Scientific Data IEEE Computing in Science & Engineering, 13 (2), pp. 40-51 (2011).

Question

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

Code

FireFlow.cxx

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkContourFilter.h>
#include <vtkGenericOutlineFilter.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 <vtkSphereSource.h>
#include <vtkStreamTracer.h>
#include <vtkTubeFilter.h>
#include <vtkUnstructuredGrid.h>
#include <vtkVRMLImporter.h>
#include <vtkXMLUnstructuredGridReader.h>

#include <iostream>
#include <string>

int main(int argc, char* argv[])
{
  if (argc < 3)
  {
    std::cerr << "Usage: " << argv[0]
              << "  geometry.wrl velocity.vtu e.g. room_vis.wrl fire_ug.vtu"
              << std::endl;
    return EXIT_FAILURE;
  }
  vtkNew<vtkNamedColors> colors;
  vtkColor3d isoSurfaceColor = colors->GetColor3d("WhiteSmoke");
  vtkColor3d sphereColor = colors->GetColor3d("hotpink");
  vtkColor3d backgroundColor = colors->GetColor3d("SlateGray");

  vtkNew<vtkRenderer> renderer;
  renderer->UseHiddenLineRemovalOn();

  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);

  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  renderWindowInteractor->SetRenderWindow(renderWindow);

  // Import the VRML Files that define the geometry.
  vtkNew<vtkVRMLImporter> vrmlImport;
  vrmlImport->SetRenderWindow(renderWindow);
  vrmlImport->SetFileName(argv[1]);
  vrmlImport->Update();

  // Read the UnstructuredGrid define the solution.
  vtkNew<vtkXMLUnstructuredGridReader> solution;
  solution->SetFileName(argv[2]);
  solution->Update();

  // Create an outline.
  vtkNew<vtkGenericOutlineFilter> outline;
  outline->SetInputConnection(solution->GetOutputPort());

  // Create Seeds.
  vtkNew<vtkPointSource> seeds;
  seeds->SetRadius(0.2);
  seeds->SetCenter(3.5, 0.625, 1.25);
  seeds->SetNumberOfPoints(50);

  // Create streamlines.
  vtkNew<vtkStreamTracer> streamTracer;
  streamTracer->SetIntegrationDirectionToBoth();
  streamTracer->SetInputConnection(solution->GetOutputPort());
  streamTracer->SetSourceConnection(seeds->GetOutputPort());
  streamTracer->SetMaximumPropagation(50);
  streamTracer->SetInitialIntegrationStep(.2);
  streamTracer->SetMinimumIntegrationStep(.01);
  streamTracer->SetIntegratorType(1);
  streamTracer->SetComputeVorticity(1);

  vtkNew<vtkTubeFilter> tubes;
  tubes->SetInputConnection(streamTracer->GetOutputPort());
  tubes->SetNumberOfSides(8);
  tubes->SetRadius(.02);
  tubes->SetVaryRadius(0);

  vtkNew<vtkPolyDataMapper> mapTubes;
  mapTubes->SetInputConnection(tubes->GetOutputPort());
  mapTubes->SetScalarRange(solution->GetOutput()->GetScalarRange());

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

  // Create an Isosurface.
  vtkNew<vtkContourFilter> isoSurface;
  isoSurface->SetValue(0, 550.0);
  isoSurface->SetInputConnection(solution->GetOutputPort());

  vtkNew<vtkPolyDataMapper> isoSurfaceMapper;
  isoSurfaceMapper->SetInputConnection(isoSurface->GetOutputPort());
  isoSurfaceMapper->ScalarVisibilityOff();

  vtkNew<vtkActor> isoSurfaceActor;
  isoSurfaceActor->SetMapper(isoSurfaceMapper);
  isoSurfaceActor->GetProperty()->SetOpacity(.5);
  isoSurfaceActor->GetProperty()->SetDiffuseColor(isoSurfaceColor.GetData());

  vtkNew<vtkSphereSource> sphere;
  sphere->SetCenter(seeds->GetCenter());
  sphere->SetRadius(seeds->GetRadius());
  sphere->SetThetaResolution(20);
  sphere->SetPhiResolution(11);
  ;
  vtkNew<vtkPolyDataMapper> sphereMapper;
  sphereMapper->SetInputConnection(sphere->GetOutputPort());

  vtkNew<vtkActor> sphereActor;
  sphereActor->SetMapper(sphereMapper);
  sphereActor->GetProperty()->SetOpacity(1.0);
  sphereActor->GetProperty()->SetSpecular(.4);
  sphereActor->GetProperty()->SetSpecularPower(80);
  sphereActor->GetProperty()->SetDiffuseColor(sphereColor.GetData());

  renderer->AddActor(tubesActor);
  renderer->AddActor(sphereActor);
  renderer->AddActor(isoSurfaceActor);

  renderer->SetBackground(backgroundColor.GetData());
  renderWindow->SetSize(640, 512);
  renderWindow->SetWindowName("FireFlow");
  renderWindow->Render();

  renderer->GetActiveCamera()->Azimuth(20.0);
  renderer->GetActiveCamera()->Elevation(10.0);
  renderer->GetActiveCamera()->Dolly(1.25);
  renderer->ResetCameraClippingRange();

  renderWindow->Render();

  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(FireFlow)

find_package(VTK COMPONENTS 
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "FireFlow: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(FireFlow MACOSX_BUNDLE FireFlow.cxx )
  target_link_libraries(FireFlow PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS FireFlow
  MODULES ${VTK_LIBRARIES}
)

Download and Build FireFlow

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

cd FireFlow/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:

./FireFlow

WINDOWS USERS

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