//============================================================================
// bvvfc.cpp : bounding-volume hierarchy ViewFrustumCuller BASE class implementation
//============================================================================

#include "bvvfc.hpp"

#ifdef STATS_ON
  // STATS GATHERING VARIABLES
  float BVvfc::_NumBVcompleteIn_;
  float BVvfc::_NumBVcompleteInObjs_;
  float BVvfc::_NumBVpartial_;
  float BVvfc::_NumBVpartialObjs_;
  float BVvfc::_NumBVcompleteOut_; 
  float BVvfc::_NumBVcompleteOutObjs_;
  float BVvfc::_NumBVvisited_;
#endif

//--------------------------------------------------------------------------
// THE "STANDARD" CULLING TRAVERSAL ROUTINE:
// RECURSIVELY TRAVERSE THE BVtree AND DETERMINE MINIMAL OVERLAPPING NODE SET.
//--------------------------------------------------------------------------
void BVvfc::CullBVtree(BVtree* BVt)
{
  CallBackVisitedBV(BVt);
  if (BVt)
  {
    int OVERLAP=BVt->OverlapVF(VF);
    if (OVERLAP==COMPLETEIN)
    {
      CallBackCompleteInBV(BVt);
    }
    else if (OVERLAP==PARTIAL)
    {
      if (BVt->IsLeaf()) CallBackPartialBV(BVt);
      else { CullBVtree(BVt->N); CullBVtree(BVt->P); }
    }
    else // OVERLAP==COMPLETEOUT
    {
      CallBackCompleteOutBV(BVt);
    }
  }
}

//--------------------------------------------------------------------------
// ALTERNATIVE CULLING TRAVERSAL ROUTINE:
// Recursively traverses the BVtree to a specified level and checks for
// overlap with the nodes at this level (or higher if leaf is reached).
// A default value of -1 is used to traverse to the leaves. Assumes at least
// one node is present.
//--------------------------------------------------------------------------
void BVvfc::CullBVtreeToLevel(BVtree* BVt, int Level=-1)
{
  CallBackVisitedBV(BVt);
  if (Level==0 || BVt->IsLeaf())
  {
    int OVERLAP=BVt->OverlapVF(VF);
    if (OVERLAP==COMPLETEIN) CallBackCompleteInBV(BVt);
    else if (OVERLAP==PARTIAL) CallBackPartialBV(BVt);
    else CallBackCompleteOutBV(BVt);
  }
  else
  {
    CullBVtreeToLevel(BVt->N, Level-1);
    CullBVtreeToLevel(BVt->P, Level-1);
  };
};