Method BuildIntersectList

renderers/agg/src/clipper.cpp:1716–1758

//------------------------------------------------------------------------------

void Clipper::BuildIntersectList(const long64 topY)
{
  if ( !m_ActiveEdges ) return;

  //prepare for sorting ...
  TEdge* e = m_ActiveEdges;
  e->tmpX = TopX( *e, topY );
  m_SortedEdges = e;
  m_SortedEdges->prevInSEL = 0;
  e = e->nextInAEL;
  while( e )
  {
    e->prevInSEL = e->prevInAEL;
    e->prevInSEL->nextInSEL = e;
    e->nextInSEL = 0;
    e->tmpX = TopX( *e, topY );
    e = e->nextInAEL;
  }

  //bubblesort ...
  bool isModified = true;
  while( isModified && m_SortedEdges )
  {
    isModified = false;
    e = m_SortedEdges;
    while( e->nextInSEL )
    {
      TEdge *eNext = e->nextInSEL;
      IntPoint pt;
      if(e->tmpX > eNext->tmpX && IntersectPoint(*e, *eNext, pt))
      {
        AddIntersectNode( e, eNext, pt );
        SwapPositionsInSEL(e, eNext);
        isModified = true;
      }
      else
        e = eNext;
    }
    if( e->prevInSEL ) e->prevInSEL->nextInSEL = 0;
    else break;
  }
  m_SortedEdges = 0;
}
//------------------------------------------------------------------------------

bool Process1Before2(IntersectNode &node1, IntersectNode &node2)