vtk调整鼠标滚轮缩放

在vtk中，可以通过以下步骤调整鼠标滚轮缩放：

1. 创建vtkRenderWindowInteractor对象并将其与vtkRenderWindow相关联：

vtkRenderWindowInteractor *interactor = vtkRenderWindowInteractor::New();
interactor->SetRenderWindow(renderWindow);

2. 创建vtkInteractorStyle对象并将其与vtkRenderWindowInteractor相关联：

vtkInteractorStyle *style = vtkInteractorStyleTrackballCamera::New();
interactor->SetInteractorStyle(style);

3. 在vtkInteractorStyle对象中，重写OnMouseWheelForward和OnMouseWheelBackward方法以实现鼠标滚轮缩放：

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

    virtual void OnMouseWheelForward()
    {
        this->Zoom(1.1);
        this->Render();
    }

    virtual void OnMouseWheelBackward()
    {
        this->Zoom(0.9);
        this->Render();
    }
};

vtkObjectFactoryMacro(CustomInteractorStyle);

4. 将自定义的vtkInteractorStyle对象设置为vtkRenderWindowInteractor的交互样式：

CustomInteractorStyle *customStyle = CustomInteractorStyle::New();
interactor->SetInteractorStyle(customStyle);

这样，当用户滚动鼠标滚轮时，vtkRenderWindow将以适当的倍率进行缩放。