VTK图形处理之剪裁

剪裁

　　剪裁的操作基本上和剪切一样，需要使用一把“刀”（隐函数）并设置剪裁值。输入的数据集被分成了两部分：裁下的部分和裁掉的部分。默认只产生裁下的部分这个输出。

示例演示

CMakeLists.txt文件代码如下：

CMAKE_MINIMUM_REQUIRED(VERSION 2.8)PROJECT(ClipExample)FIND_PACKAGE(VTK REQUIRED)INCLUDE(${VTK_USE_FILE})ADD_EXECUTABLE(ClipExample Clip.cpp)TARGET_LINK_LIBRARIES(ClipExample ${VTK_LIBRARIES})

C++代码：

#include "vtkActor.h"#include "vtkXMLPolyDataReader.h"#include "vtkClipPolyData.h"#include "vtkPlane.h"#include "vtkPolyData.h"#include "vtkPolyDataMapper.h"#include "vtkPolyDataNormals.h"#include "vtkProperty.h"#include "vtkRenderWindow.h"#include "vtkRenderWindowInteractor.h"#include "vtkRenderer.h"#include "vtkSmartPointer.h"#include "vtkInteractorStyleTrackballCamera.h"int main(){    //read input data    vtkSmartPointer<vtkXMLPolyDataReader> reader = vtkSmartPointer<vtkXMLPolyDataReader>::New();    reader->SetFileName("E:\\TestData\\cow.vtp");    vtkSmartPointer<vtkPolyDataNormals> cow_normals = vtkSmartPointer<vtkPolyDataNormals>::New();    cow_normals->SetInputConnection(reader->GetOutputPort());    vtkSmartPointer<vtkPlane> plane = vtkSmartPointer<vtkPlane>::New();    plane->SetOrigin(0.25, 0.0, 0.0);    plane->SetNormal(-1, -1, 0);    vtkSmartPointer<vtkClipPolyData> clipper = vtkSmartPointer<vtkClipPolyData>::New();    clipper->SetInputConnection(cow_normals->GetOutputPort());    clipper->SetClipFunction(plane);    clipper->GenerateClipScalarsOn();    clipper->GenerateClippedOutputOn();    clipper->SetValue(0.5);    vtkSmartPointer<vtkPolyDataMapper> clip_mapper = vtkSmartPointer<vtkPolyDataMapper>::New();    clip_mapper->SetInputConnection(clipper->GetOutputPort());    clip_mapper->ScalarVisibilityOff();    vtkSmartPointer<vtkProperty> backProp = vtkSmartPointer<vtkProperty>::New();    backProp->SetDiffuseColor(1.00, 0.388, 0.278);    vtkSmartPointer<vtkActor> clip_actor = vtkSmartPointer<vtkActor>::New();    clip_actor->SetMapper(clip_mapper);    clip_actor->GetProperty()->SetColor(.200, .631, .788);    clip_actor->SetBackfaceProperty(backProp);    vtkSmartPointer<vtkPolyDataMapper> rest_mapper = vtkSmartPointer<vtkPolyDataMapper>::New();    rest_mapper->SetInputConnection(clipper->GetClippedOutputPort());    rest_mapper->ScalarVisibilityOff();    vtkSmartPointer<vtkActor> rest_actor = vtkSmartPointer<vtkActor>::New();    rest_actor->SetMapper(rest_mapper);    rest_actor->GetProperty()->SetRepresentationToWireframe();    vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();    renderer->AddActor(clip_actor);    renderer->AddActor(rest_actor);    renderer->SetBackground(1.0, 1.0, 1.0);    vtkSmartPointer<vtkRenderWindow> renWin = vtkSmartPointer<vtkRenderWindow>::New();    renWin->AddRenderer(renderer);    renWin->SetSize(640, 480);    renWin->Render();    renWin->SetWindowName("ClipExample");    vtkSmartPointer<vtkRenderWindowInteractor> iren =        vtkSmartPointer<vtkRenderWindowInteractor>::New();    iren->SetRenderWindow(renWin);    vtkSmartPointer<vtkInteractorStyleTrackballCamera> style =        vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();    iren->SetInteractorStyle(style);    iren->Initialize();    iren->Start();    return EXIT_SUCCESS;}

运行结果：

图中颜色显示部分是裁下的部分PolyData数据，而裁掉的部分以线框的形式显示。