SphereWidget2
VTKExamples/Cxx/Widgets/SphereWidget2
Description
The spherical coordinates of the widget's handle match the coordinates that it displays in the window. The world coordinates of the handle are also shown.
Code
SphereWidget2.cxx
#include <vtkCommand.h>
#include <vtkMath.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkSmartPointer.h>
#include <vtkSphere.h>
#include <vtkSphereRepresentation.h>
#include <vtkSphereWidget2.h>
// Callback that displays the sphere widget's spherical handle postion
// in both sphercial (relative to the widget's center) and cartesian global coordinates
class vtkSphereCallback : public vtkCommand
{
public:
static vtkSphereCallback *New()
{
return new vtkSphereCallback;
}
virtual void Execute(vtkObject *caller, unsigned long, void*)
{
vtkSphereWidget2 *sphereWidget =
reinterpret_cast<vtkSphereWidget2*>(caller);
double center[3], handlePosition[3];
vtkSphereRepresentation* sphereRepresentation =
vtkSphereRepresentation::SafeDownCast( sphereWidget->GetRepresentation() );
sphereRepresentation->GetHandlePosition( handlePosition );
sphereRepresentation->GetSphere( this->Sphere );
this->Sphere->GetCenter( center );
double radius = sqrt( static_cast<double>(vtkMath::Distance2BetweenPoints( center, handlePosition ) ) );
radius = (radius <= 0.0 ? 1.0 : radius );
double theta = vtkMath::DegreesFromRadians( atan2( ( handlePosition[1] - center[1] ), ( handlePosition[0] - center[0] ) ) );
double phi = vtkMath::DegreesFromRadians( acos( ( handlePosition[2] - center[2] ) / radius ) );
std::cout << "r, theta, phi: ("
<< std::setprecision(3)
<< radius << ", " << theta << ", " << phi << ") "
<< "x, y, z: ("
<< handlePosition[0] << ", "
<< handlePosition[1] << ", "
<< handlePosition[2] << ") "
<< std::endl;
}
vtkSphereCallback(){ this->Sphere = vtkSphere::New(); }
~vtkSphereCallback(){ this->Sphere->Delete(); }
vtkSphere* Sphere;
};
int main( int, char *[] )
{
// Create a renderer and a render window
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
// Create an interactor
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
// Create a sphere widget
vtkSmartPointer<vtkSphereWidget2> sphereWidget =
vtkSmartPointer<vtkSphereWidget2>::New();
sphereWidget->SetInteractor(renderWindowInteractor);
sphereWidget->CreateDefaultRepresentation();
vtkSphereRepresentation* sphereRepresentation =
vtkSphereRepresentation::SafeDownCast( sphereWidget->GetRepresentation() );
sphereRepresentation->HandleVisibilityOn();
vtkSmartPointer<vtkSphereCallback> sphereCallback =
vtkSmartPointer<vtkSphereCallback>::New();
sphereWidget->AddObserver( vtkCommand::InteractionEvent, sphereCallback );
renderWindow->Render();
renderWindowInteractor->Initialize();
renderWindow->Render();
sphereWidget->On();
// Begin mouse interaction
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(SphereWidget2)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(SphereWidget2 MACOSX_BUNDLE SphereWidget2.cxx)
target_link_libraries(SphereWidget2 ${VTK_LIBRARIES})
Download and Build SphereWidget2
Click here to download SphereWidget2 and its CMakeLists.txt file. Once the tarball SphereWidget2.tar has been downloaded and extracted,
cd SphereWidget2/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:
./SphereWidget2
WINDOWS USERS PLEASE NOTE: Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.