Method TidyEdges

CPP/Clipper2Lib/src/clipper.rectclip.cpp:665–841

  }

  void RectClip64::TidyEdges(size_t idx, OutPt2List& cw, OutPt2List& ccw)
  {
    if (ccw.empty()) return;
    bool isHorz = ((idx == 1) || (idx == 3));
    bool cwIsTowardLarger = ((idx == 1) || (idx == 2));
    size_t i = 0, j = 0;
    OutPt2* p1, * p2, * p1a, * p2a, * op, * op2;

    while (i < cw.size())
    {
      p1 = cw[i];
      if (!p1 || p1->next == p1->prev)
      {
        cw[i++] = nullptr;
        j = 0;
        continue;
      }

      size_t jLim = ccw.size();
      while (j < jLim &&
        (!ccw[j] || ccw[j]->next == ccw[j]->prev)) ++j;

      if (j == jLim)
      {
        ++i;
        j = 0;
        continue;
      }

      if (cwIsTowardLarger)
      {
        // p1 >>>> p1a;
        // p2 <<<< p2a;
        p1 = cw[i]->prev;
        p1a = cw[i];
        p2 = ccw[j];
        p2a = ccw[j]->prev;
      }
      else
      {
        // p1 <<<< p1a;
        // p2 >>>> p2a;
        p1 = cw[i];
        p1a = cw[i]->prev;
        p2 = ccw[j]->prev;
        p2a = ccw[j];
      }

      if ((isHorz && !HasHorzOverlap(p1->pt, p1a->pt, p2->pt, p2a->pt)) ||
        (!isHorz && !HasVertOverlap(p1->pt, p1a->pt, p2->pt, p2a->pt)))
      {
        ++j;
        continue;
      }

      // to get here we're either splitting or rejoining
      bool isRejoining = cw[i]->owner_idx != ccw[j]->owner_idx;