VTK 视角的旋转、平移、缩放

在CAD/CAM软件中，都需要旋转、平移和缩放视角，来观察操作图形。由于VTK定义的交互的类型不是很适用，所有通过定义一套自己的交互方式。

在下面代码中，鼠标左键平移，滚轮缩放，右键旋转。

先定义一个交互类型。继承自vtkInteractorStyleTrackballCamera，并且交换按键。

class Normal3DCameraStyle : public vtkInteractorStyleTrackballCamera
{
public:
    static Normal3DCameraStyle* New();
    vtkTypeMacro(Normal3DCameraStyle, vtkInteractorStyleTrackballCamera);

    virtual void OnLeftButtonDown(void);
    virtual void OnLeftButtonUp(void);
    virtual void OnRightButtonDown(void);
    virtual void OnRightButtonUp(void);
    virtual void OnMiddleButtonDown(void);
    virtual void OnMiddleButtonUp(void);
    virtual void OnMouseWheelForward(void);
    virtual void OnMouseWheelBackward(void);
    virtual void OnMouseMove(void);
};

vtkStandardNewMacro(Normal3DCameraStyle);//必须加！！！！

void Normal3DCameraStyle::OnLeftButtonDown(void)
{
    vtkInteractorStyleTrackballCamera::OnMiddleButtonDown();
}

void Normal3DCameraStyle::OnLeftButtonUp(void)
{
    vtkInteractorStyleTrackballCamera::OnMiddleButtonUp();
}

void Normal3DCameraStyle::OnRightButtonDown(void)
{
    vtkInteractorStyleTrackballCamera::OnLeftButtonDown();
}

void Normal3DCameraStyle::OnRightButtonUp(void)
{
    vtkInteractorStyleTrackballCamera::OnLeftButtonUp();
}

void Normal3DCameraStyle::OnMiddleButtonDown(void)
{

}

void Normal3DCameraStyle::OnMiddleButtonUp(void)
{

}

void Normal3DCameraStyle::OnMouseWheelForward(void)
{
    vtkInteractorStyleTrackballCamera::OnMouseWheelForward();
};

void Normal3DCameraStyle::OnMouseWheelBackward(void)
{
    vtkInteractorStyleTrackballCamera::OnMouseWheelBackward();
};

void Normal3DCameraStyle::OnMouseMove(void)
{
    vtkInteractorStyleTrackballCamera::OnMouseMove();
}
  

添加Normal3DCameraStyle到交换器中

vtkNew<Normal3DCameraStyle> style;
ui.vtk_main->interactor()->SetInteractorStyle(style);

下面是完整代码

class Normal3DCameraStyle : public vtkInteractorStyleTrackballCamera
{
public:
    static Normal3DCameraStyle* New();
    vtkTypeMacro(Normal3DCameraStyle, vtkInteractorStyleTrackballCamera);

    virtual void OnLeftButtonDown(void);
    virtual void OnLeftButtonUp(void);
    virtual void OnRightButtonDown(void);
    virtual void OnRightButtonUp(void);
    virtual void OnMiddleButtonDown(void);
    virtual void OnMiddleButtonUp(void);
    virtual void OnMouseWheelForward(void);
    virtual void OnMouseWheelBackward(void);
    virtual void OnMouseMove(void);
};

vtkStandardNewMacro(Normal3DCameraStyle);//必须加！！！！

void Normal3DCameraStyle::OnLeftButtonDown(void)
{
    vtkInteractorStyleTrackballCamera::OnMiddleButtonDown();
}

void Normal3DCameraStyle::OnLeftButtonUp(void)
{
    vtkInteractorStyleTrackballCamera::OnMiddleButtonUp();
}

void Normal3DCameraStyle::OnRightButtonDown(void)
{
    vtkInteractorStyleTrackballCamera::OnLeftButtonDown();
}

void Normal3DCameraStyle::OnRightButtonUp(void)
{
    vtkInteractorStyleTrackballCamera::OnLeftButtonUp();
}

void Normal3DCameraStyle::OnMiddleButtonDown(void)
{

}

void Normal3DCameraStyle::OnMiddleButtonUp(void)
{

}

void Normal3DCameraStyle::OnMouseWheelForward(void)
{
    vtkInteractorStyleTrackballCamera::OnMouseWheelForward();
};

void Normal3DCameraStyle::OnMouseWheelBackward(void)
{
    vtkInteractorStyleTrackballCamera::OnMouseWheelBackward();
};

void Normal3DCameraStyle::OnMouseMove(void)
{
    vtkInteractorStyleTrackballCamera::OnMouseMove();
}  

QtVtkTest::QtVtkTest(QWidget *parent)
    : QMainWindow(parent)
{
    ui.setupUi(this);

    QSurfaceFormat::setDefaultFormat(QVTKOpenGLNativeWidget::defaultFormat());

    vtkNew<vtkRenderer> renderer;
    vtkNew<vtkNamedColors> colors;

    //定义球
    vtkNew<vtkSphereSource> sphereSource;
    sphereSource->SetRadius(5);
    sphereSource->SetCenter(5, 0, 0);
    vtkNew<vtkPolyDataMapper> sphereMapper;
    sphereMapper->SetInputConnection(sphereSource->GetOutputPort());
    vtkNew<vtkActor> sphereActor;
    sphereActor->SetMapper(sphereMapper);
    sphereActor->GetProperty()->SetColor(colors->GetColor4d("Green").GetData());
    sphereActor->GetProperty()->EdgeVisibilityOn(); //显示线框

    renderer->AddActor(sphereActor);

    renderer->SetBackground(colors->GetColor3d("SteelBlue").GetData());

    vtkNew<vtkGenericOpenGLRenderWindow> renderWindow;
    renderWindow->AddRenderer(renderer);
    renderWindow->SetWindowName("RenderWindowNoUIFile");

    ui.vtk_main->setRenderWindow(renderWindow);
    //
    vtkNew<Normal3DCameraStyle> style;
    ui.vtk_main->interactor()->SetInteractorStyle(style);
}