/// <summary>
/// 添加洞
/// </summary>
/// <param name="line"></param>
public void AddHole(PolyLine line)
{
line.SafeCloseLine();
line.Counterclockwise();
_lines.Add(line);
}
/// <summary>
/// 添加边界
/// </summary>
/// <param name="line"></param>
public void AddEdge(PolyLine line)
{
line.SafeCloseLine();
line.Clockwise();
_lines.Add(line);
}