WarpCombustor
vtk-examples/Cxx/VisualizationAlgorithms/WarpCombustor
Description¶
This example demonstrates how to extract "computational planes" from a structured dataset. Structured data has a natural, logical coordinate system based on i-j-k indices. Specifying imin,imax, jmin,jmax, kmin,kmax pairs can indicate a point, line, plane, or volume of data.
In this example, we extract three planes and warp them using scalar values in the direction of the local normal at each point. This gives a sort of "velocity profile" that indicates the nature of the flow.
Info
See Figure 9-4b in Chapter 9 The VTK Textbook.
Other languages
See (Python)
Question
If you have a question about this example, please use the VTK Discourse Forum
Code¶
WarpCombustor.cxx
#include <vtkActor.h>
#include <vtkAppendPolyData.h>
#include <vtkCamera.h>
#include <vtkMultiBlockDataSet.h>
#include <vtkMultiBlockPLOT3DReader.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkPolyDataNormals.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkStructuredGrid.h>
#include <vtkStructuredGridGeometryFilter.h>
#include <vtkStructuredGridOutlineFilter.h>
#include <vtkWarpScalar.h>
#include <iostream>
#include <string>
// This example demonstrates how to extract "computational planes" from a
// structured dataset. Structured data has a natural, logical coordinate
// system based on i-j-k indices. Specifying imin,imax, jmin,jmax, kmin,kmax
// pairs can indicate a point, line, plane, or volume of data.
//
// In this example, we extract three planes and warp them using scalar values
// in the direction of the local normal at each point. This gives a sort of
// "velocity profile" that indicates the nature of the flow.
int main(int argc, char* argv[])
{
if (argc < 3)
{
std::cout << "Usage: " << argv[0] << " combxyz.bin combq.bin" << std::endl;
return EXIT_FAILURE;
}
// Here we read data from a annular combustor. A combustor burns fuel and air
// in a gas turbine (e.g., a jet engine) and the hot gas eventually makes its
// way to the turbine section.
//
vtkNew<vtkMultiBlockPLOT3DReader> pl3d;
pl3d->SetXYZFileName(argv[1]);
pl3d->SetQFileName(argv[2]);
pl3d->SetScalarFunctionNumber(100);
pl3d->SetVectorFunctionNumber(202);
pl3d->Update();
vtkStructuredGrid* pl3dOutput =
dynamic_cast<vtkStructuredGrid*>(pl3d->GetOutput()->GetBlock(0));
// Planes are specified using a imin,imax, jmin,jmax, kmin,kmax coordinate
// specification. Min and max i,j,k values are clamped to 0 and maximum value.
//
vtkNew<vtkStructuredGridGeometryFilter> plane;
plane->SetInputData(pl3dOutput);
plane->SetExtent(10, 10, 1, 100, 1, 100);
vtkNew<vtkStructuredGridGeometryFilter> plane2;
plane2->SetInputData(pl3dOutput);
plane2->SetExtent(30, 30, 1, 100, 1, 100);
vtkNew<vtkStructuredGridGeometryFilter> plane3;
plane3->SetInputData(pl3dOutput);
plane3->SetExtent(45, 45, 1, 100, 1, 100);
// We use an append filter because that way we can do the warping, etc. just
// using a single pipeline and actor.
//
vtkNew<vtkAppendPolyData> appendF;
appendF->AddInputConnection(plane->GetOutputPort());
appendF->AddInputConnection(plane2->GetOutputPort());
appendF->AddInputConnection(plane3->GetOutputPort());
vtkNew<vtkWarpScalar> warp;
warp->SetInputConnection(appendF->GetOutputPort());
warp->UseNormalOn();
warp->SetNormal(1.0, 0.0, 0.0);
warp->SetScaleFactor(2.5);
vtkNew<vtkPolyDataNormals> normals;
normals->SetInputConnection(warp->GetOutputPort());
normals->SetFeatureAngle(60);
vtkNew<vtkPolyDataMapper> planeMapper;
planeMapper->SetInputConnection(normals->GetOutputPort());
planeMapper->SetScalarRange(pl3dOutput->GetScalarRange());
vtkNew<vtkActor> planeActor;
planeActor->SetMapper(planeMapper);
// The outline provides context for the data and the planes.
vtkNew<vtkStructuredGridOutlineFilter> outline;
outline->SetInputData(pl3dOutput);
vtkNew<vtkPolyDataMapper> outlineMapper;
outlineMapper->SetInputConnection(outline->GetOutputPort());
vtkNew<vtkNamedColors> colors;
vtkNew<vtkActor> outlineActor;
outlineActor->SetMapper(outlineMapper);
outlineActor->GetProperty()->SetColor(colors->GetColor3d("Black").GetData());
// Create the usual graphics stuff.
//
vtkNew<vtkRenderer> ren1;
vtkNew<vtkRenderWindow> renWin;
renWin->AddRenderer(ren1);
vtkNew<vtkRenderWindowInteractor> iren;
iren->SetRenderWindow(renWin);
ren1->AddActor(outlineActor);
ren1->AddActor(planeActor);
ren1->SetBackground(colors->GetColor3d("Silver").GetData());
renWin->SetSize(640, 480);
renWin->SetWindowName("WarpCombustor");
// Create an initial view.
ren1->GetActiveCamera()->SetClippingRange(3.95297, 50);
ren1->GetActiveCamera()->SetFocalPoint(8.88908, 0.595038, 29.3342);
ren1->GetActiveCamera()->SetPosition(-12.3332, 31.7479, 41.2387);
ren1->GetActiveCamera()->SetViewUp(0.060772, -0.319905, 0.945498);
iren->Initialize();
// Render the image.
//
renWin->Render();
iren->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(WarpCombustor)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "WarpCombustor: 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(WarpCombustor MACOSX_BUNDLE WarpCombustor.cxx )
target_link_libraries(WarpCombustor PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS WarpCombustor
MODULES ${VTK_LIBRARIES}
)
Download and Build WarpCombustor¶
Click here to download WarpCombustor and its CMakeLists.txt file. Once the tarball WarpCombustor.tar has been downloaded and extracted,
cd WarpCombustor/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:
./WarpCombustor
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.