Method TryToReplace

tools/poly_borders/borders_data.cpp:308–384

}

base::ControlFlow BordersData::TryToReplace(size_t curBorderId, size_t & curLeftPointId, size_t curRightPointId)
{
  auto & curPolygon = m_bordersPolygons[curBorderId];
  if (curRightPointId >= curPolygon.m_points.size())
    return base::ControlFlow::Break;

  if (curPolygon.IsFrozen(curRightPointId, curRightPointId))
  {
    curLeftPointId = curRightPointId - 1;
    return base::ControlFlow::Break;
  }

  auto & leftMarkedPoint = curPolygon.m_points[curLeftPointId];
  auto & rightMarkedPoint = curPolygon.m_points[curRightPointId];

  auto op = rightMarkedPoint.GetLink(curBorderId);
  if (!op)
    return base::ControlFlow::Continue;

  Link rightLink = *op;
  Link leftLink = *leftMarkedPoint.GetLink(curBorderId);

  if (leftLink.m_borderId != rightLink.m_borderId)
    return base::ControlFlow::Continue;

  auto const anotherBorderId = leftLink.m_borderId;
  auto const anotherLeftPointId = leftLink.m_pointId;
  auto const anotherRightPointId = rightLink.m_pointId;
  auto & anotherPolygon = m_bordersPolygons[anotherBorderId];

  if (anotherPolygon.IsFrozen(std::min(anotherLeftPointId, anotherRightPointId),
                              std::max(anotherLeftPointId, anotherRightPointId)))
  {
    return base::ControlFlow::Continue;
  }

  auto const anotherSubpolygon =
      AppendPointsWithAnyDirection(anotherPolygon.m_points, anotherLeftPointId, anotherRightPointId);

  auto const curSubpolygon = AppendPointsWithAnyDirection(curPolygon.m_points, curLeftPointId, curRightPointId);

  if (!NeedReplace(curSubpolygon, anotherSubpolygon))
    return base::ControlFlow::Break;

  // We want to decrease the amount of points in polygons. So we will replace the greater amounts of
  // points by smaller amounts of points.
  bool const curLenIsLess = curSubpolygon.size() < anotherSubpolygon.size();

  size_t dstFrom = curLenIsLess ? anotherLeftPointId : curLeftPointId;
  size_t dstTo = curLenIsLess ? anotherRightPointId : curRightPointId;

  size_t srcFrom = curLenIsLess ? curLeftPointId : anotherLeftPointId;
  size_t srcTo = curLenIsLess ? curRightPointId : anotherRightPointId;

  size_t const borderIdWhereAreaWillBeChanged = curLenIsLess ? anotherBorderId : curBorderId;
  size_t const srcBorderId = curLenIsLess ? curBorderId : anotherBorderId;

  bool const reversed = IsReversedIntervals(dstFrom, dstTo, srcFrom, srcTo);