VTK 实例18：柱体的交互

#include "vtkAutoInit.h" 
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);

#include <vtkSmartPointer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkCylinderSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkProperty.h>

int main()
{
    //定义一个vtkCylinderSource类型的对象cylinder
    //vtkCylinderSource主要是生成一个中心在渲染场景原点的柱体，类型为（vtkPolyData)
    vtkSmartPointer<vtkCylinderSource> cylinder = 
        vtkSmartPointer<vtkCylinderSource>::New();
    cylinder->SetHeight( 3.0 );//设置柱体的高
    cylinder->SetRadius( 1.0 );//设置柱体横截面半径
    cylinder->SetResolution( 10 ); //设置柱体横截面的等边多边形的边数

    //将输入的数据转换为几何图元（点、线、多边形）进行渲染
    vtkSmartPointer<vtkPolyDataMapper> cylinderMapper = 
        vtkSmartPointer<vtkPolyDataMapper>::New();
    cylinderMapper->SetInputConnection( cylinder->GetOutputPort() ); 

    vtkSmartPointer<vtkActor> cylinderActor = 
        vtkSmartPointer<vtkActor>::New();
    //设置生成几何图元的Mapper,即连接一个Actor到可视化管线的末端
    cylinderActor->SetMapper( cylinderMapper );
    cylinderActor->GetProperty()->SetColor(1.0, 0.0, 0.0);

    vtkSmartPointer<vtkRenderer> renderer = 
        vtkSmartPointer<vtkRenderer>::New();
    renderer->AddActor( cylinderActor );
    renderer->SetBackground( 1.0, 1.0, 1.0 );

    //将操作系统与VTK渲染引擎连接到一起
    vtkSmartPointer<vtkRenderWindow> renWin = 
        vtkSmartPointer<vtkRenderWindow>::New();
    renWin->AddRenderer( renderer );//加入vtkRenderer对象
    renWin->SetSize( 640, 480 );//设置窗口大小，像素为单位
    renWin->Render();//场景渲染
    renWin->SetWindowName("RenderCylinder");

    //提供平台独立的响应鼠标、键盘和时钟事件的交互机制
    vtkSmartPointer<vtkRenderWindowInteractor> iren = 
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
    iren->SetRenderWindow(renWin);

    //交互器样式的一种，可通过控制相机对物体作旋转、放大、缩小等操作
    vtkSmartPointer<vtkInteractorStyleTrackballCamera> style = 
        vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();
    iren->SetInteractorStyle(style);

    iren->Initialize();
    iren->Start();

    return EXIT_SUCCESS;
}