c++ - How to cut a plane in a user-designed object using vtk? -

for example, want design sphere radius 256 , origin (0.0,0.0,0.0). , want cut plane through origin , display cross-section. wiki of vtk of how generate sphere :http://www.vtk.org/wiki/vtk/examples/cxx/geometricobjects/sphere , how slice image after reading pics:http://www.vtk.org/gitweb?p=vtk.git;a=blob;f=examples/imageprocessing/cxx/imageslicing.cxx . want combine 2 pieces of codes accomplish this. fails.because says input of vtkimagereslice should object of class vtkimagedata vtkploydata.so how change vtkpolydata vtkimagedata?here code.

#include "vtksmartpointer.h" #include "vtkimagereader2.h" #include "vtkmatrix4x4.h"  #include "vtkimagereslice.h" #include "vtklookuptable.h" #include "vtkimagemaptocolors.h" #include "vtkimageactor.h" #include "vtkrenderer.h" #include "vtkrenderwindow.h" #include "vtkrenderwindowinteractor.h" #include "vtkinteractorstyleimage.h" #include "vtkcommand.h" #include "vtkimagedata.h" #include "vtkimagemapper3d.h" #include "vtkstreamingdemanddrivenpipeline.h" #include "vtkinformation.h" #include "vtkspheresource.h" // mouse motion callback, turn "slicing" on , off class vtkimageinteractioncallback : public vtkcommand { public:  static vtkimageinteractioncallback *new() {     return new vtkimageinteractioncallback; };  vtkimageinteractioncallback() {     this->slicing = 0;     this->imagereslice = 0;     this->interactor = 0; };  void setimagereslice(vtkimagereslice *reslice) {     this->imagereslice = reslice; };  vtkimagereslice *getimagereslice() {     return this->imagereslice; };  void setinteractor(vtkrenderwindowinteractor *interactor) {     this->interactor = interactor; };  vtkrenderwindowinteractor *getinteractor() {     return this->interactor; };  virtual void execute(vtkobject *, unsigned long event, void *) {     vtkrenderwindowinteractor *interactor = this->getinteractor();      int lastpos[2];     interactor->getlasteventposition(lastpos);     int currpos[2];     interactor->geteventposition(currpos);      if (event == vtkcommand::leftbuttonpressevent)     {         this->slicing = 1;     }     else if (event == vtkcommand::leftbuttonreleaseevent)     {         this->slicing = 0;     }     else if (event == vtkcommand::mousemoveevent)     {         if (this->slicing)         {             vtkimagereslice *reslice = this->imagereslice;              // increment slice position deltay of mouse             int deltay = lastpos[1] - currpos[1];              reslice->update();             double slicespacing = reslice->getoutput()->getspacing()[2];             vtkmatrix4x4 *matrix = reslice->getresliceaxes();             // move center point slicing through             double point[4];             double center[4];             point[0] = 0.0;             point[1] = 0.0;             point[2] = slicespacing * deltay;             point[3] = 1.0;             matrix->multiplypoint(point, center);             matrix->setelement(0, 3, center[0]);             matrix->setelement(1, 3, center[1]);             matrix->setelement(2, 3, center[2]);             interactor->render();         }         else         {             vtkinteractorstyle *style = vtkinteractorstyle::safedowncast(                 interactor->getinteractorstyle());             if (style)             {                 style->onmousemove();             }         }     } };  private:  // actions (slicing only, now) int slicing;  // pointer vtkimagereslice vtkimagereslice *imagereslice;  // pointer interactor vtkrenderwindowinteractor *interactor; };  // program entry point int main(int argc, char *argv[]) { // generate sphere radius 256.0 , origin (0.0,0.0,0.0) vtksmartpointer<vtkspheresource> sphere = vtksmartpointer<vtkspheresource>::new(); sphere->setcenter(0.0, 0.0, 0.0); sphere->setradius(256.0); sphere->update();  static double sagittalelements[16] = {     0, 0, -1, 0,     1, 0, 0, 0,     0, -1, 0, 0,     0, 0, 0, 1 };   // set slice orientation vtksmartpointer<vtkmatrix4x4> resliceaxes =     vtksmartpointer<vtkmatrix4x4>::new(); resliceaxes->deepcopy(sagittalelements); // set point through slice resliceaxes->setelement(0, 3, 0); resliceaxes->setelement(1, 3, 0); resliceaxes->setelement(2, 3, 0);  // extract slice in desired orientation vtksmartpointer<vtkimagereslice> reslice =     vtksmartpointer<vtkimagereslice>::new(); reslice->setinputconnection(sphere->getoutputport()); reslice->setoutputdimensionality(2); reslice->setresliceaxes(resliceaxes); reslice->setinterpolationmodetolinear();  // create greyscale lookup table vtksmartpointer<vtklookuptable> table =     vtksmartpointer<vtklookuptable>::new(); table->setrange(0, 2000); // image intensity range table->setvaluerange(0.0, 1.0); // black white table->setsaturationrange(0.0, 0.0); // no color saturation table->setramptolinear(); table->build();  // map image through lookup table vtksmartpointer<vtkimagemaptocolors> color =     vtksmartpointer<vtkimagemaptocolors>::new(); color->setlookuptable(table); color->setinputconnection(reslice->getoutputport());  // display image vtksmartpointer<vtkimageactor> actor =     vtksmartpointer<vtkimageactor>::new(); actor->getmapper()->setinputconnection(color->getoutputport());  vtksmartpointer<vtkrenderer> renderer =     vtksmartpointer<vtkrenderer>::new(); renderer->addactor(actor);  vtksmartpointer<vtkrenderwindow> window =     vtksmartpointer<vtkrenderwindow>::new(); window->addrenderer(renderer);  // set interaction vtksmartpointer<vtkinteractorstyleimage> imagestyle =     vtksmartpointer<vtkinteractorstyleimage>::new(); vtksmartpointer<vtkrenderwindowinteractor> interactor =     vtksmartpointer<vtkrenderwindowinteractor>::new(); interactor->setinteractorstyle(imagestyle); window->setinteractor(interactor); window->render();  vtksmartpointer<vtkimageinteractioncallback> callback =     vtksmartpointer<vtkimageinteractioncallback>::new(); callback->setimagereslice(reslice); callback->setinteractor(interactor);  imagestyle->addobserver(vtkcommand::mousemoveevent, callback); imagestyle->addobserver(vtkcommand::leftbuttonpressevent, callback); imagestyle->addobserver(vtkcommand::leftbuttonreleaseevent, callback);  // start interaction // start() method doesn't return until window closed user interactor->start();  return exit_success; } 

thanks kun yang

no conversion needed. use vtkclippolydata poly -> poly filter.