AffineWidget
Repository source: AffineWidget
Description¶
This example demonstrates use of a vtkAffineWidget to apply transforms to a 3D prop in the x-y plane.
Other languages
See (PythonicAPI)
Question
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Code¶
AffineWidget.cxx
#include <vtkActor.h>
#include <vtkAffineRepresentation2D.h>
#include <vtkAffineWidget.h>
#include <vtkAppendPolyData.h>
#include <vtkCallbackCommand.h>
#include <vtkCommand.h>
#include <vtkInteractorStyleSwitch.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 <vtkSphereSource.h>
#include <vtkTransform.h>
namespace {
class vtkAffineCallback : public vtkCallbackCommand
{
public:
static vtkAffineCallback* New()
{
return new vtkAffineCallback;
}
virtual void Execute(vtkObject* caller, unsigned long, void*);
vtkAffineCallback() : Actor(0), AffineRep(0)
{
this->Transform = vtkTransform::New();
}
~vtkAffineCallback()
{
this->Transform->Delete();
}
vtkActor* Actor;
vtkAffineRepresentation2D* AffineRep;
vtkTransform* Transform;
};
} // namespace
int main(int, char*[])
{
vtkNew<vtkNamedColors> colors;
// Create two spheres: a larger one and a smaller one on top of the larger one
// to show a reference point while rotating
vtkNew<vtkSphereSource> sphereSource;
sphereSource->Update();
vtkNew<vtkSphereSource> sphereSource2;
sphereSource2->SetRadius(0.075);
sphereSource2->SetCenter(0, 0.5, 0);
sphereSource2->Update();
// Append the two spheres into one vtkPolyData
vtkNew<vtkAppendPolyData> append;
append->AddInputConnection(sphereSource->GetOutputPort());
append->AddInputConnection(sphereSource2->GetOutputPort());
// Create a plane centered over the larger sphere with 4x4 sub sections
vtkNew<vtkPlaneSource> planeSource;
planeSource->SetXResolution(4);
planeSource->SetYResolution(4);
planeSource->SetOrigin(-1, -1, 0);
planeSource->SetPoint1(1, -1, 0);
planeSource->SetPoint2(-1, 1, 0);
// Create a mapper and actor for the plane: show it as a wireframe
vtkNew<vtkPolyDataMapper> planeMapper;
planeMapper->SetInputConnection(planeSource->GetOutputPort());
vtkNew<vtkActor> planeActor;
planeActor->SetMapper(planeMapper);
planeActor->GetProperty()->SetRepresentationToWireframe();
planeActor->GetProperty()->SetColor(colors->GetColor3d("Red").GetData());
// Create a mapper and actor for the spheres
vtkNew<vtkPolyDataMapper> mapper;
mapper->SetInputConnection(append->GetOutputPort());
vtkNew<vtkActor> actor;
actor->SetMapper(mapper);
// Create a renderer and render window
vtkNew<vtkRenderer> renderer;
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->AddRenderer(renderer);
renderWindow->SetWindowName("AffineWidget");
renderer->AddActor(actor);
renderer->AddActor(planeActor);
renderer->GradientBackgroundOn();
renderer->SetBackground(colors->GetColor3d("LightSkyBlue").GetData());
renderer->SetBackground2(colors->GetColor3d("MidnightBlue").GetData());
// Create an interactor
vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
renderWindowInteractor->SetRenderWindow(renderWindow);
dynamic_cast<vtkInteractorStyleSwitch*>(
renderWindowInteractor->GetInteractorStyle())
->SetCurrentStyleToTrackballCamera();
// Create an affine widget to manipulate the actor
// the widget currently only has a 2D representation and therefore applies
// transforms in the X-Y plane only
vtkNew<vtkAffineWidget> affineWidget;
affineWidget->SetInteractor(renderWindowInteractor);
affineWidget->CreateDefaultRepresentation();
dynamic_cast<vtkAffineRepresentation2D*>(affineWidget->GetRepresentation())
->PlaceWidget(actor->GetBounds());
vtkNew<vtkAffineCallback> affineCallback;
affineCallback->Actor = actor;
affineCallback->AffineRep = dynamic_cast<vtkAffineRepresentation2D*>(
affineWidget->GetRepresentation());
affineWidget->AddObserver(vtkCommand::InteractionEvent, affineCallback);
affineWidget->AddObserver(vtkCommand::EndInteractionEvent, affineCallback);
renderWindow->Render();
renderWindowInteractor->Initialize();
renderWindow->Render();
affineWidget->On();
// begin mouse interaction
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
namespace {
void vtkAffineCallback::Execute(vtkObject*, unsigned long vtkNotUsed(event),
void*)
{
this->AffineRep->GetTransform(this->Transform);
this->Actor->SetUserTransform(this->Transform);
}
} // namespace
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(AffineWidget)
find_package(VTK COMPONENTS
CommonColor
CommonCore
CommonTransforms
FiltersCore
FiltersSources
InteractionStyle
InteractionWidgets
RenderingContextOpenGL2
RenderingCore
RenderingFreeType
RenderingGL2PSOpenGL2
RenderingOpenGL2
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "AffineWidget: 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(AffineWidget MACOSX_BUNDLE AffineWidget.cxx )
target_link_libraries(AffineWidget PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS AffineWidget
MODULES ${VTK_LIBRARIES}
)
Download and Build AffineWidget¶
Click here to download AffineWidget and its CMakeLists.txt file. Once the tarball AffineWidget.tar has been downloaded and extracted,
cd AffineWidget/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:
./AffineWidget
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.