DrawText
vtk-examples/Cxx/Visualization/DrawText
Description¶
This example writes "Hello world" in the bottom left corner of the render window. The text size and color are set. There are many properties that can be set that control how the text is changed when the render window is resized, but they are not covered in this example.
This example draws text in 2D. For an example using 3D text that can be placed on the scene like a regular vtkActor, see VectorText. For an example of drawing text, also in 2D, but into a vtkImageData object rather than into the render window, see ImageText.
Seealso
Other languages
See (Java)
Question
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Code¶
DrawText.cxx
#include <vtkActor.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>
#include <vtkTextActor.h>
#include <vtkTextProperty.h>
int main(int, char*[])
{
vtkNew<vtkNamedColors> colors;
// Create a sphere
vtkNew<vtkSphereSource> sphereSource;
sphereSource->SetCenter(0.0, 0.0, 0.0);
sphereSource->SetRadius(5.0);
sphereSource->Update();
// Create a mapper
vtkNew<vtkPolyDataMapper> mapper;
mapper->SetInputData(sphereSource->GetOutput());
// Create an actor
vtkNew<vtkActor> actor;
actor->SetMapper(mapper);
// Create a renderer
vtkNew<vtkRenderer> renderer;
actor->GetProperty()->SetColor(colors->GetColor3d("MistyRose").GetData());
renderer->AddActor(actor);
renderer->SetBackground(colors->GetColor3d("SlateGray").GetData());
// Create a render window
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->AddRenderer(renderer);
renderWindow->SetWindowName("DrawText");
// Create an interactor
vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
renderWindowInteractor->SetRenderWindow(renderWindow);
// Setup the text and add it to the renderer
vtkNew<vtkTextActor> textActor;
textActor->SetInput("Hello world");
textActor->SetPosition2(10, 40);
textActor->GetTextProperty()->SetFontSize(24);
textActor->GetTextProperty()->SetColor(colors->GetColor3d("Gold").GetData());
renderer->AddActor2D(textActor);
// Render and interact
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(DrawText)
find_package(VTK COMPONENTS
vtkCommonColor
vtkCommonCore
vtkCommonDataModel
vtkFiltersSources
vtkInteractionStyle
vtkRenderingContextOpenGL2
vtkRenderingCore
vtkRenderingFreeType
vtkRenderingGL2PSOpenGL2
vtkRenderingOpenGL2
QUIET
)
if (NOT VTK_FOUND)
message("Skipping DrawText: ${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(DrawText MACOSX_BUNDLE DrawText.cxx )
target_link_libraries(DrawText PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(DrawText MACOSX_BUNDLE DrawText.cxx )
target_link_libraries(DrawText PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS DrawText
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build DrawText¶
Click here to download DrawText and its CMakeLists.txt file. Once the tarball DrawText.tar has been downloaded and extracted,
cd DrawText/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:
./DrawText
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.