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/*=========================================================================
Program: Visualization Toolkit
Module: Cone6.cxx
Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
All rights reserved.
See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notice for more information.
=========================================================================*/
//
// This example introduces 3D widgets. 3D widgets take advantage of the
// event/observer design pattern introduced previously. They typically
// have a particular representation in the scene which can be interactively
// selected and manipulated using the mouse and keyboard. As the widgets
// are manipulated, they in turn invoke events such as StartInteractionEvent,
// InteractionEvent, and EndInteractionEvent which can be used to manipulate
// the scene that the widget is embedded in. 3D widgets work in the context
// of the event loop which was set up in the previous example.
//
// Note: there are more 3D widget examples in VTK/Examples/GUI/.
//
// First include the required header files for the VTK classes we are using.
#include "vtkConeSource.h"
#include "vtkPolyDataMapper.h"
#include "vtkRenderWindow.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkCamera.h"
#include "vtkActor.h"
#include "vtkRenderer.h"
#include "vtkCommand.h"
#include "vtkBoxWidget.h"
#include "vtkTransform.h"
#include "vtkInteractorStyleTrackballCamera.h"
//
// Similar to Cone2.cxx, we define a callback for interaction.
//
class vtkMyCallback : public vtkCommand
{
public:
static vtkMyCallback *New()
{ return new vtkMyCallback; }
void Execute(vtkObject *caller, unsigned long, void*) VTK_OVERRIDE
{
vtkTransform *t = vtkTransform::New();
vtkBoxWidget *widget = reinterpret_cast<vtkBoxWidget*>(caller);
widget->GetTransform(t);
widget->GetProp3D()->SetUserTransform(t);
t->Delete();
}
};
int main()
{
//
// Next we create an instance of vtkConeSource and set some of its
// properties. The instance of vtkConeSource "cone" is part of a
// visualization pipeline (it is a source process object); it produces data
// (output type is vtkPolyData) which other filters may process.
//
vtkConeSource *cone = vtkConeSource::New();
cone->SetHeight( 3.0 );
cone->SetRadius( 1.0 );
cone->SetResolution( 10 );
//
// In this example we terminate the pipeline with a mapper process object.
// (Intermediate filters such as vtkShrinkPolyData could be inserted in
// between the source and the mapper.) We create an instance of
// vtkPolyDataMapper to map the polygonal data into graphics primitives. We
// connect the output of the cone souece to the input of this mapper.
//
vtkPolyDataMapper *coneMapper = vtkPolyDataMapper::New();
coneMapper->SetInputConnection( cone->GetOutputPort() );
//
// Create an actor to represent the cone. The actor orchestrates rendering
// of the mapper's graphics primitives. An actor also refers to properties
// via a vtkProperty instance, and includes an internal transformation
// matrix. We set this actor's mapper to be coneMapper which we created
// above.
//
vtkActor *coneActor = vtkActor::New();
coneActor->SetMapper( coneMapper );
//
// Create the Renderer and assign actors to it. A renderer is like a
// viewport. It is part or all of a window on the screen and it is
// responsible for drawing the actors it has. We also set the background
// color here.
//
vtkRenderer *ren1= vtkRenderer::New();
ren1->AddActor( coneActor );
ren1->SetBackground( 0.1, 0.2, 0.4 );
//
// Finally we create the render window which will show up on the screen.
// We put our renderer into the render window using AddRenderer. We also
// set the size to be 300 pixels by 300.
//
vtkRenderWindow *renWin = vtkRenderWindow::New();
renWin->AddRenderer( ren1 );
renWin->SetSize( 300, 300 );
//
// The vtkRenderWindowInteractor class watches for events (e.g., keypress,
// mouse) in the vtkRenderWindow. These events are translated into
// event invocations that VTK understands (see VTK/Common/vtkCommand.h
// for all events that VTK processes). Then observers of these VTK
// events can process them as appropriate.
vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
iren->SetRenderWindow(renWin);
//
// By default the vtkRenderWindowInteractor instantiates an instance
// of vtkInteractorStyle. vtkInteractorStyle translates a set of events
// it observes into operations on the camera, actors, and/or properties
// in the vtkRenderWindow associated with the vtkRenderWinodwInteractor.
// Here we specify a particular interactor style.
vtkInteractorStyleTrackballCamera *style =
vtkInteractorStyleTrackballCamera::New();
iren->SetInteractorStyle(style);
//
// Here we use a vtkBoxWidget to transform the underlying coneActor (by
// manipulating its transformation matrix). Many other types of widgets
// are available for use, see the documentation for more details.
//
// The SetInteractor method is how 3D widgets are associated with the render
// window interactor. Internally, SetInteractor sets up a bunch of callbacks
// using the Command/Observer mechanism (AddObserver()). The place factor
// controls the initial size of the widget with respect to the bounding box
// of the input to the widget.
vtkBoxWidget *boxWidget = vtkBoxWidget::New();
boxWidget->SetInteractor(iren);
boxWidget->SetPlaceFactor(1.25);
//
// Place the interactor initially. The input to a 3D widget is used to
// initially position and scale the widget. The EndInteractionEvent is
// observed which invokes the SelectPolygons callback.
//
boxWidget->SetProp3D(coneActor);
boxWidget->PlaceWidget();
vtkMyCallback *callback = vtkMyCallback::New();
boxWidget->AddObserver(vtkCommand::InteractionEvent, callback);
//
// Normally the user presses the "i" key to bring a 3D widget to life. Here
// we will manually enable it so it appears with the cone.
//
boxWidget->On();
//
// Start the event loop.
//
iren->Initialize();
iren->Start();
//
// Free up any objects we created. All instances in VTK are deleted by
// using the Delete() method.
//
cone->Delete();
coneMapper->Delete();
coneActor->Delete();
callback->Delete();
boxWidget->Delete();
ren1->Delete();
renWin->Delete();
iren->Delete();
style->Delete();
return 0;
}
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