EVE/EveBase/TEveJetConeGL.cxx

   1 // @(#)root/eve:$Id$
   2 // Author: Matevz Tadel 2007
   3
   4 /*************************************************************************
   5  * Copyright (C) 1995-2007, Rene Brun and Fons Rademakers.               *
   6  * All rights reserved.                                                  *
   7  *                                                                       *
   8  * For the licensing terms see $ROOTSYS/LICENSE.                         *
   9  * For the list of contributors see $ROOTSYS/README/CREDITS.             *
  10  *************************************************************************/
  11
  12 #include "TEveJetConeGL.h"
  13 #include "TEveJetCone.h"
  14
  15 #include "TMath.h"
  16
  17 #include "TGLRnrCtx.h"
  18 #include "TGLIncludes.h"
  19
  20 //______________________________________________________________________________
  21 // OpenGL renderer class for TEveJetCone.
  22 //
  23
  24 ClassImp(TEveJetConeGL)
  25
  26 //______________________________________________________________________________
  27 TEveJetConeGL::TEveJetConeGL() :
  28    TGLObject(), fM(0)
  29 {
  30    // Constructor.
  31
  32    // fDLCache = kFALSE; // Disable display list.
  33 }
  34
  35 /******************************************************************************/
  36
  37 //______________________________________________________________________________
  38 Bool_t TEveJetConeGL::SetModel(TObject* obj, const Option_t* /*opt*/)
  39 {
  40    // Set model object.
  41
  42    if (SetModelCheckClass(obj, TEveJetCone::Class())) {
  43       fM = dynamic_cast<TEveJetCone*>(obj);
  44       return kTRUE;
  45    }
  46    return kFALSE;
  47 }
  48
  49 //______________________________________________________________________________
  50 void TEveJetConeGL::SetBBox()
  51 {
  52    // Set bounding box.
  53
  54    // !! This ok if master sub-classed from TAttBBox
  55    SetAxisAlignedBBox(((TEveJetCone*)fExternalObj)->AssertBBox());
  56 }
  57
  58 /******************************************************************************/
  59
  60 //______________________________________________________________________________
  61 void TEveJetConeGL::DirectDraw(TGLRnrCtx & rnrCtx) const
  62 {
  63    // Render with OpenGL.
  64
  65    printf("TEveJetConeGL::DirectDraw LOD %d\n", rnrCtx.CombiLOD());
  66
  67    glPushAttrib(GL_ENABLE_BIT | GL_POLYGON_BIT);
  68
  69    glDisable(GL_CULL_FACE);
  70    glEnable(GL_NORMALIZE);
  71
  72    glBegin(GL_TRIANGLE_FAN);
  73    glVertex3fv(fM->fApex);
  74    if ( fM->fBasePoints.size() > 2)
  75    {
  76       TEveJetCone::vTEveVector_ci prev = fM->fBasePoints.end(); --prev;
  77       TEveJetCone::vTEveVector_ci i    = fM->fBasePoints.begin();
  78       TEveJetCone::vTEveVector_ci next = i; ++next;
  79
  80       TEveVector norm_buf;
  81       TEveVector beg_normal = TMath::Cross((*i - fM->fApex).Arr(), (*next - *prev).Arr(), norm_buf.Arr());
  82
  83       glNormal3fv(beg_normal);
  84       glVertex3fv(fM->fBasePoints.front());
  85
  86       prev = i;  i = next;  ++next;
  87
  88       while (i != fM->fBasePoints.begin())
  89       {
  90          glNormal3fv(TMath::Cross((*i - fM->fApex).Arr(), (*next - *prev).Arr(), norm_buf.Arr()));
  91          glVertex3fv(*i);
  92
  93          prev = i;
  94          i    = next;
  95          ++next; if (next == fM->fBasePoints.end()) next = fM->fBasePoints.begin();
  96       }
  97
  98       glNormal3fv(beg_normal);
  99       glVertex3fv(fM->fBasePoints.front());
 100    }
 101    glEnd();
 102
 103    glPopAttrib();
 104 }