CreateBFont
vtk-examples/Cxx/VisualizationAlgorithms/CreateBFont
Description¶
A scanned image clipped with a scalar value of 1/2 its maximum intensity produces a mixture of quadrilaterals and triangles.
Info
See Figure 9-10 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¶
CreateBFont.cxx
#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkClipPolyData.h>
#include <vtkImageDataGeometryFilter.h>
#include <vtkImageGaussianSmooth.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPNMReader.h>
#include <vtkPointData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <iostream>
#include <string>
int main(int argc, char* argv[])
{
if (argc < 2)
{
std::cout << "Usage: " << argv[0] << " image.pgm e.g. B.pgm" << std::endl;
return EXIT_FAILURE;
}
// Now create the RenderWindow, Renderer and Interactor.
//
vtkNew<vtkNamedColors> colors;
vtkNew<vtkRenderer> ren1;
vtkNew<vtkRenderWindow> renWin;
renWin->AddRenderer(ren1);
vtkNew<vtkRenderWindowInteractor> iren;
iren->SetRenderWindow(renWin);
vtkNew<vtkPNMReader> imageIn;
imageIn->SetFileName(argv[1]);
vtkNew<vtkImageGaussianSmooth> gaussian;
gaussian->SetStandardDeviations(2, 2);
gaussian->SetDimensionality(2);
gaussian->SetRadiusFactors(1, 1);
gaussian->SetInputConnection(imageIn->GetOutputPort());
vtkNew<vtkImageDataGeometryFilter> geometry;
geometry->SetInputConnection(gaussian->GetOutputPort());
vtkNew<vtkClipPolyData> aClipper;
aClipper->SetInputConnection(geometry->GetOutputPort());
aClipper->SetValue(127.5);
aClipper->GenerateClipScalarsOff();
aClipper->InsideOutOn();
aClipper->GetOutput()->GetPointData()->CopyScalarsOff();
aClipper->Update();
vtkNew<vtkPolyDataMapper> mapper;
mapper->SetInputConnection(aClipper->GetOutputPort());
mapper->ScalarVisibilityOff();
vtkNew<vtkActor> letter;
letter->SetMapper(mapper);
ren1->AddActor(letter);
letter->GetProperty()->SetDiffuseColor(
colors->GetColor3d("LampBlack").GetData());
letter->GetProperty()->SetRepresentationToWireframe();
ren1->SetBackground(colors->GetColor3d("WhiteSmoke").GetData());
ren1->ResetCamera();
ren1->GetActiveCamera()->Dolly(1.2);
ren1->ResetCameraClippingRange();
renWin->SetSize(640, 480);
renWin->SetWindowName("CreateBFont");
// Render the image.
//
renWin->Render();
iren->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(CreateBFont)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "CreateBFont: 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(CreateBFont MACOSX_BUNDLE CreateBFont.cxx )
target_link_libraries(CreateBFont PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS CreateBFont
MODULES ${VTK_LIBRARIES}
)
Download and Build CreateBFont¶
Click here to download CreateBFont and its CMakeLists.txt file. Once the tarball CreateBFont.tar has been downloaded and extracted,
cd CreateBFont/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:
./CreateBFont
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.