/// <summary>
/// 将一个actor保存为stl格式
/// </summary>
/// <param name="actor"></param>
void SaveActorToStl(vtkActor actor, string stlFileName)
{
//通过actor模型生成stl文件
vtkPolyDataMapper mapper = (vtkPolyDataMapper)actor.GetMapper();//获取mapper
vtkPolyData polyData = vtkPolyData.New();
polyData = mapper.GetInput();//从mapper中提取数据
vtkTriangleFilter filter = vtkTriangleFilter.New();
filter.SetInput(polyData);//三角化后才能保存为正常的stl格式
vtkSTLWriter stlWriter = vtkSTLWriter.New();
stlWriter.SetFileName(stlFileName);
stlWriter.SetInputConnection(filter.GetOutputPort());//提取数据
stlWriter.Write();
}