StreamLines
vtk-examples/Cxx/Visualization/StreamLines
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Code¶
StreamLines.cxx
#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkMultiBlockDataSet.h>
#include <vtkMultiBlockPLOT3DReader.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPlaneSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkStreamTracer.h>
#include <vtkStructuredGridOutlineFilter.h>
#include <iostream>
#include <string>
int main(int argc, char* argv[])
{
if (argc < 3)
{
std::cerr << "Required arguments: xyzFile qFile e.g. combxyz.bin combq.bin"
<< std::endl;
return EXIT_FAILURE;
}
vtkNew<vtkNamedColors> namedColors;
std::string xyzFile = argv[1]; // "combxyz.bin";
std::string qFile = argv[2]; // "combq.bin";
vtkNew<vtkMultiBlockPLOT3DReader> pl3d;
pl3d->SetXYZFileName(xyzFile.c_str());
pl3d->SetQFileName(qFile.c_str());
pl3d->SetScalarFunctionNumber(100);
pl3d->SetVectorFunctionNumber(202);
pl3d->Update();
// Source of the streamlines
vtkNew<vtkPlaneSource> seeds;
seeds->SetXResolution(4);
seeds->SetYResolution(4);
seeds->SetOrigin(2, -2, 26);
seeds->SetPoint1(2, 2, 26);
seeds->SetPoint2(2, -2, 32);
// Streamline itself
vtkNew<vtkStreamTracer> streamLine;
pl3d->Update();
streamLine->SetInputData(pl3d->GetOutput()->GetBlock(0));
streamLine->SetSourceConnection(seeds->GetOutputPort());
streamLine->SetMaximumPropagation(100);
streamLine->SetInitialIntegrationStep(0.1);
streamLine->SetIntegrationDirectionToBoth();
// streamLine->SetStartPosition(2,-2,30);
// as alternative to the SetSource(), which can handle multiple
// streamlines, you can set a SINGLE streamline from
// SetStartPosition()
vtkNew<vtkPolyDataMapper> streamLineMapper;
streamLineMapper->SetInputConnection(streamLine->GetOutputPort());
vtkNew<vtkActor> streamLineActor;
streamLineActor->SetMapper(streamLineMapper);
streamLineActor->VisibilityOn();
// Outline-Filter for the grid
vtkNew<vtkStructuredGridOutlineFilter> outline;
outline->SetInputData(pl3d->GetOutput()->GetBlock(0));
vtkNew<vtkPolyDataMapper> outlineMapper;
outlineMapper->SetInputConnection(outline->GetOutputPort());
vtkNew<vtkActor> outlineActor;
outlineActor->SetMapper(outlineMapper);
outlineActor->GetProperty()->SetColor(
namedColors->GetColor3d("White").GetData());
// Create the RenderWindow, Renderer and Actors
vtkNew<vtkRenderer> renderer;
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->AddRenderer(renderer);
renderWindow->SetWindowName("StreamLines");
vtkNew<vtkRenderWindowInteractor> interactor;
interactor->SetRenderWindow(renderWindow);
vtkNew<vtkInteractorStyleTrackballCamera> style;
interactor->SetInteractorStyle(style);
renderer->AddActor(streamLineActor);
renderer->AddActor(outlineActor);
// Add the actors to the renderer, set the background and size
renderer->SetBackground(namedColors->GetColor3d("MidnightBlue").GetData());
renderWindow->SetSize(300, 300);
interactor->Initialize();
renderWindow->Render();
renderer->GetActiveCamera()->SetPosition(-32.8, -12.3, 46.3);
renderer->GetActiveCamera()->SetFocalPoint(8.3, 0.03, 29.8);
renderer->GetActiveCamera()->SetViewUp(0.2, 0.5, 0.9);
renderWindow->Render();
interactor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(StreamLines)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "StreamLines: 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(StreamLines MACOSX_BUNDLE StreamLines.cxx )
target_link_libraries(StreamLines PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS StreamLines
MODULES ${VTK_LIBRARIES}
)
Download and Build StreamLines¶
Click here to download StreamLines and its CMakeLists.txt file. Once the tarball StreamLines.tar has been downloaded and extracted,
cd StreamLines/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:
./StreamLines
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.