[实验]用VTK给立方体贴纹理

今天需要用vtk实现贴图功能，搜遍网上居然都没有找到很好的学习资料，只是找到一篇写于07年的“vtk中的纹理贴图详解”里面有一个例子，是在一个平面上贴图，但我要实现的是三维空间中的贴图，类似于在一个立方体上面贴图，有参考的例子了，开始实验：

1、VTK纹理贴图基础：

见vtk中的纹理贴图详解(点击进入)

 

 

2、实验开始：

 

预定义

 #define NFACE 6
 #define NLINE 4
 #define M_GET_LENGTH3D(x, y, z)   sqrt((double)((x)*(x) + (y)*(y) + (z)*(z)))//---------------------------------------------------------
 typedef struct _T_PT3D_T_
 {
  double      x, y, z;
 }
 PT3D;

 

先是定义数据，先是生成一个vtkUnstructuredGrid的立方体数据

  //首先定义立方体的8个点
  //       a-----------b   //顶
  //       /           /
  //     /           /
  //     c-----------d //       aa-----------bb  //底
  //       /           /
  //     /           /
  //     cc-----------dd
  PT3D pa,pb,pc,pd,paa,pbb,pcc,pdd;
  paa.x = paa.y = paa.z = 0;
  pbb.x = pbb.z = 0; pbb.y = 1;
  pcc.y = pcc.z = 0; pcc.x = 1;
  pdd.x = pdd.y = 1; pdd.z = 0;
  pa.x = pa.y = 0; pa.z = 1;
  pb.y = pb.z = 1; pb.x = 0;
  pc.x = pc.z = 1; pc.y = 0;
  pd.x = pd.y = pd.z = 1; vtkUnstructuredGrid *mycube = vtkUnstructuredGrid::New();
  vtkPoints *points = vtkPoints::New();
  points->InsertPoint(0, paa.x, paa.y, paa.z);//0->aa
  points->InsertPoint(1, pbb.x, pbb.y, pbb.z);//1->bb
  points->InsertPoint(2, pcc.x, pcc.y, pcc.z);//2->cc
  points->InsertPoint(3, pdd.x, pdd.y, pdd.z);//3->dd
  points->InsertPoint(4, pa.x, pa.y, pa.z);//4->a
  points->InsertPoint(5, pb.x, pb.y, pb.z);//5->b
  points->InsertPoint(6, pc.x, pc.y, pc.z);//6->c
  points->InsertPoint(7, pd.x, pd.y, pd.z);//7->d
  mycube->SetPoints(points);
  //int facesIndex[6][4] = {{  下   },{  上   },{  左   },{  右   },{  前   },{  后   }};
  //int facesIndex[6][4] = {{aa-bb-dd-cc},{a-b-d-c},{aa-a-c-cc},{bb-b-d-dd},{cc-c-d-dd},{aa-a-b-bb}};
  int facesIndex[NFACE][NLINE] = {{0,1,3,2},{4,5,7,6},{0,4,6,2},{1,5,7,3},{2,6,7,3},{0,4,5,1}};
  //int facesIndex[NFACE][NLINE] = {{6,0,2},{6,0,1},{6,2,3},{6,1,3}};


  for (int iFace = 0; iFace < NFACE; iFace++)
  {
   mycube->InsertNextCell(VTK_POLYGON,NLINE,facesIndex[iFace]);
  }

 

然后读取纹理数据，纹理文件见附件

 //读取纹理图像
 vtkBMPReader *bmpReader = vtkBMPReader::New();
 bmpReader->SetFileName("D:\\CPlusPlusOpenSource\\MyTest\\01VTKtest\\test_project\\masonry.bmp");
 vtkTexture *atext = vtkTexture::New();
 atext->SetInputConnection(bmpReader->GetOutputPort());
 atext->InterpolateOn();

生成polydata

 //将点和多边形加入polydata
  vtkCellArray *faces = mycube->GetCells();
  vtkPolyData *profile = vtkPolyData::New();
  profile->SetPoints(points);
  profile->SetPolys(faces);

 

纹理配制，这里面主要试验的就是tmapper三个参数的设置

 //计算多边形的发向量。
  vtkPolyDataNormals *normal = vtkPolyDataNormals::New();
  normal->SetInput(profile);

  //设置多边形的纹理映射模式
  //设置为plane模式
  vtkTextureMapToPlane *tmapper = vtkTextureMapToPlane::New();
  tmapper->SetInputConnection(normal->GetOutputPort());

  //设置纹理st坐标系的顶点坐标 和两点坐标，定义了st坐标系
  //下面这一部分就是下面要试验的！
  tmapper->SetOrigin(paa.x, paa.y, paa.z);
  tmapper->SetPoint1(pa.x, pa.y, pa.z);
  tmapper->SetPoint2(pbb.x, pbb.y, pbb.z);
  //对纹理映射进行计算
  vtkTransformTextureCoords *xform = vtkTransformTextureCoords::New();
  xform->SetInputConnection(tmapper->GetOutputPort());
  //设置贴图重复比例 第一项是指s 第二项是指t 第三项是指r 一般是1
  //14：1是根据上面点坐标的数据估算出来的。如果将t坐标定义为1，那么就将纹理向s方向贴14格，也就是说，纹理在这个面片上横着14张，这里因为是正方形直接用1，1
  xform->SetScale(10, 1, 1);

最后是数据的显示

 //将数据放入polydata
  vtkPolyDataMapper *weightedTransMapper = vtkPolyDataMapper::New();
  weightedTransMapper->SetInputConnection(xform->GetOutputPort());

  //将数据放入actor
  vtkActor *weightedTransActor = vtkActor::New();
  weightedTransActor->SetMapper(weightedTransMapper);
  weightedTransActor->SetTexture(atext);


  //进行显示
  vtkRenderer *ren1 = vtkRenderer::New();
  vtkRenderWindow *renWin = vtkRenderWindow::New();
  renWin->AddRenderer(ren1);
  vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
  vtkInteractorStyleTrackballCamera *style = vtkInteractorStyleTrackballCamera::New();
  iren->SetInteractorStyle(style);
  iren->SetRenderWindow(renWin); ren1->AddActor(weightedTransActor);
  //ren1->SetBackground(0.1, 0.2, 0.5);
  ren1->SetBackground(0.3, 0.3, 0.3);
  renWin->SetSize(788, 588);

   ren1->GetActiveCamera()->Azimuth(90);
   ren1->GetActiveCamera()->Dolly(0);
  ren1->ResetCamera();
  ren1->GetActiveCamera()->Zoom(1);

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

3 实验结果

下面两个是实验不规则六面体和三角面贴图的效果

 

4 结果分析

基于上面的例子发现最后还是只能一片片贴，效率还是很低的，感觉这里面是要把不同的面片按照法线的方向来分类，一类用一个vtkTransformTextureCoords（vtkTextureMapToPlane），但不知道具体怎么操作~

5 源码

源码见附件，另外附件里的源码做了一个小小的优化，里面使用了vtkAppendPolyData把vtkTransformTextureCoords的结果append到一起，然后render，这样生成的速度还是很慢，但是至少交互的速度还行

啊，没找到传附件的地方。。。先插入纹理原件吧：（本来是bmp插进来变成jif自己转一下吧）

 

源码直接贴到下面吧，其实跟上面的步骤也差不多：

CubeTexture.cpp

 

 //          vtk中的纹理贴图要用 vtkTextureMapToPlane vtkTextureMapToSphere        //
 //              vtkTextureMapToCylinder与 vtkTransformTextureCoords                //
 //                      配合使用才能达到最好的效果。                            //
 //                                                                                //
 //                  目前vtk只支持2维纹理，3维纹理似乎并不支持。                      //
 //                                                                                //
 //                      那么vtk的纹理是如何工作的呢？？                             //
 //                                                                                //
 //                  那么我们通过自己的一段代码来解释一下：                       //
 //                                                                                //
 //               http://blog.csdn.net/yqxx/article/details/1671900                //
 //                                                                                //
 //                  在原代码的基础上修改成立方体贴纹理                             //
 //                      2011年8月27日  [email protected]                           //


 #include "vtkActor.h"
 #include "vtkCamera.h"
 #include "vtkBMPReader.h"
 #include "vtkCellArray.h"
 #include "vtkPoints.h"
 #include "vtkPolyData.h"
 #include "vtkPolyDataMapper.h"
 #include "vtkPolyDataNormals.h"
 #include "vtkRenderWindow.h"
 #include "vtkRenderWindowInteractor.h"
 #include "vtkRenderer.h"
 #include "vtkTexture.h"
 #include "vtkTextureMapToPlane.h"
 #include "vtkTextureMapToSphere.h"
 #include "vtkTransformTextureCoords.h"
 #include "vtkTextureMapToCylinder.h"
 #include "vtkProperty.h"
 #include
 #include
 #include
 #include
 #include

 // #define NFACE 4
 // #define NLINE 3
 #define NFACE 6
 #define NLINE 4
 #define M_GET_LENGTH3D(x, y, z)         sqrt((double)((x)*(x) + (y)*(y) + (z)*(z)))

 //---------------------------------------------------------
 typedef struct _T_PT3D_T_
 {
     double                      x, y, z;
 }
 PT3D;

 int main()
 {
     //首先定义立方体的8个点
     //       a-----------b   //顶
     //       /           /
     //      /           /
     //     c-----------d

     //       aa-----------bb  //底
     //       /           /
     //      /           /
     //     cc-----------dd
     PT3D pa,pb,pc,pd,paa,pbb,pcc,pdd;
     paa.x = paa.y = paa.z = 0;
     pbb.x = pbb.z = 0; pbb.y = 1;
     pcc.y = pcc.z = 0; pcc.x = 1;
     pdd.x = pdd.y = 1; pdd.z = 0;
     pa.x = pa.y = 0; pa.z = 1;
     pb.y = pb.z = 1; pb.x = 0;
     pc.x = pc.z = 1; pc.y = 0;
     pd.x = pd.y = pd.z = 1;

     vtkUnstructuredGrid *mycube = vtkUnstructuredGrid::New();
     vtkPoints *points = vtkPoints::New();
     points->InsertPoint(0, paa.x, paa.y, paa.z);//0->aa
     points->InsertPoint(1, pbb.x, pbb.y, pbb.z);//1->bb
     points->InsertPoint(2, pcc.x, pcc.y, pcc.z);//2->cc
     points->InsertPoint(3, pdd.x, pdd.y, pdd.z);//3->dd
     points->InsertPoint(4, pa.x, pa.y, pa.z);//4->a
     points->InsertPoint(5, pb.x, pb.y, pb.z);//5->b
     points->InsertPoint(6, pc.x, pc.y, pc.z);//6->c
     points->InsertPoint(7, pd.x, pd.y, pd.z);//7->d
     mycube->SetPoints(points);
     //int facesIndex[6][4] = {{  下   },{  上   },{  左   },{  右   },{  前   },{  后   }};
     //int facesIndex[6][4] = {{aa-bb-dd-cc},{a-b-d-c},{aa-a-c-cc},{bb-b-d-dd},{cc-c-d-dd},{aa-a-b-bb}};
     int facesIndex[NFACE][NLINE] = {{0,1,3,2},{4,5,7,6},{0,4,6,2},{1,5,7,3},{2,6,7,3},{0,4,5,1}};
     //int facesIndex[NFACE][NLINE] = {{6,0,2},{6,0,1},{6,2,3},{6,1,3}};


     for (int iFace = 0; iFace < NFACE; iFace++)
     {
         mycube->InsertNextCell(VTK_POLYGON,NLINE,facesIndex[iFace]);
     }

     //使用vtkUnstructuredGrid是为了跟我后面要写的程序对接，实际上可以直接通过下面的方式定义顶点索引
     //vtkCellArray *faces = vtkCellArray::New();
     //faces->InsertNextCell(4);//face aa-bb-cc-dd(下)
     //faces->InsertCellPoint(0);
     //faces->InsertCellPoint(1);
     //faces->InsertCellPoint(2);
     //faces->InsertCellPoint(3);

     //faces->InsertNextCell(4);//face a-b-c-d(上)
     //faces->InsertCellPoint(4);
     //faces->InsertCellPoint(5);
     //faces->InsertCellPoint(6);
     //faces->InsertCellPoint(7);

     //faces->InsertNextCell(4);//face aa-a-c-cc(左)
     //faces->InsertCellPoint(0);
     //faces->InsertCellPoint(4);
     //faces->InsertCellPoint(6);
     //faces->InsertCellPoint(2);

     //faces->InsertNextCell(4);//face bb-b-d-dd(右)
     //faces->InsertCellPoint(1);
     //faces->InsertCellPoint(5);
     //faces->InsertCellPoint(7);
     //faces->InsertCellPoint(3);

     //faces->InsertNextCell(4);//face cc-c-d-dd(前)
     //faces->InsertCellPoint(2);
     //faces->InsertCellPoint(6);
     //faces->InsertCellPoint(7);
     //faces->InsertCellPoint(3);

     //faces->InsertNextCell(4);//face aa-a-b-bb(后)
     //faces->InsertCellPoint(0);
     //faces->InsertCellPoint(4);
     //faces->InsertCellPoint(5);
     //faces->InsertCellPoint(1);

     //读取纹理图像
     vtkBMPReader *bmpReader = vtkBMPReader::New();
     bmpReader->SetFileName("D:\\CPlusPlusOpenSource\\MyTest\\01VTKtest\\test_project\\masonry.bmp");
     vtkTexture *atext = vtkTexture::New();
     atext->SetInputConnection(bmpReader->GetOutputPort());
     atext->InterpolateOn();

     //将点和多边形加入polydata
     vtkCellArray *faces = mycube->GetCells();
     //vtkPolyData *profile = vtkPolyData::New();
     vtkIdType *indices;
     vtkIdType numberOfPoints;
     PT3D pt0,pt1,pt2;
     //vtkAssembly * CubeAssembly = vtkAssembly::New();
     vtkAppendPolyData * CaVectorAppendPoly = vtkAppendPolyData::New();
     for (faces->InitTraversal();faces->GetNextCell(numberOfPoints, indices);)
     {
         vtkPolyData *profile = vtkPolyData::New();
         vtkCellArray *lines = vtkCellArray::New();
         lines->InsertNextCell(numberOfPoints);//#number of points
         for (vtkIdType i = 0; i < numberOfPoints; i++)
         {
             lines->InsertCellPoint(indices[i]);
             //lines->InsertCellPoint(i);
             double point[3];
             points->GetPoint(indices[i], point);
             if (numberOfPoints < 4)
             {
                 if (i == 1)
                 {
                     pt0.x = point[0];pt0.y = point[1];pt0.z = point[2];
                 }
                 if (i == 2)
                 {
                     pt1.x = point[0];pt1.y = point[1];pt1.z = point[2];
                 }
                 if (i == 0)
                 {
                     pt2.x = point[0];pt2.y = point[1];pt2.z = point[2];
                 }
             }
             else //提供对三角面片的支持
             {
                 if (i == 0)
                 {
                     pt0.x = point[0];pt0.y = point[1];pt0.z = point[2];
                 }
                 if (i == 1)
                 {
                     pt1.x = point[0];pt1.y = point[1];pt1.z = point[2];
                 }
                 if (i == 3)
                 {
                     pt2.x = point[0];pt2.y = point[1];pt2.z = point[2];
                 }

             }
         }
         profile->SetPoints(points);
         profile->SetPolys(lines);

         //计算多边形的法向量。
         vtkPolyDataNormals *normal = vtkPolyDataNormals::New();
         normal->SetInput(profile);

         //设置多边形的纹理映射模式
         //设置为plane模式
         vtkTextureMapToPlane *tmapper = vtkTextureMapToPlane::New();
         tmapper->SetInputConnection(normal->GetOutputPort());

         //设置纹理st坐标系的顶点坐标 和两点坐标，定义了st坐标系
         tmapper->SetOrigin(pt0.x, pt0.y, pt0.z);
         tmapper->SetPoint1(pt1.x, pt1.y, pt1.z);
         tmapper->SetPoint2(pt2.x, pt2.y, pt2.z);

         //对纹理映射进行计算
         vtkTransformTextureCoords *xform = vtkTransformTextureCoords::New();
         xform->SetInputConnection(tmapper->GetOutputPort());
         //设置贴图重复比例 第一项是指s 第二项是指t 第三项是指r 一般是1
         //14：1是根据上面点坐标的数据估算出来的。如果将t坐标定义为1，那么就将纹理向s方向贴14格，也就是说，纹理在这个面片上横着14张
         xform->SetScale(1, 1, 1);

         //append，这样只需要一个actor
         CaVectorAppendPoly->AddInput((vtkPolyData*)xform->GetOutput());
     }

     //将数据放入polydata
     vtkPolyDataMapper *weightedTransMapper = vtkPolyDataMapper::New();
     weightedTransMapper->SetInputConnection(CaVectorAppendPoly->GetOutputPort());

     //将数据放入actor
     vtkActor *weightedTransActor = vtkActor::New();
     weightedTransActor->SetMapper(weightedTransMapper);
     weightedTransActor->SetTexture(atext);

     atext->Delete();
     points->Delete();

     //进行显示
     vtkRenderer *ren1 = vtkRenderer::New();
     vtkRenderWindow *renWin = vtkRenderWindow::New();
     renWin->AddRenderer(ren1);
     vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
     vtkInteractorStyleTrackballCamera *style = vtkInteractorStyleTrackballCamera::New();
     iren->SetInteractorStyle(style);
     iren->SetRenderWindow(renWin);

     //ren1->AddActor(weightedTransActor);
     ren1->AddActor(weightedTransActor);
     //ren1->SetBackground(0.1, 0.2, 0.5);
     ren1->SetBackground(0.3, 0.3, 0.3);
     renWin->SetSize(788, 588);

     ren1->GetActiveCamera()->Azimuth(90);
     ren1->GetActiveCamera()->Dolly(0);
     ren1->ResetCamera();
     ren1->GetActiveCamera()->Zoom(1);

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

     return 0;
 }

From:  http://blog.csdn.net/nowen/article/details/6725760