Reference IPath

  IPath = interface(ICloneable<IPathData>)
  public
    { Leave the current path opened and add a new sub path }
    procedure Add;
    { Remove the current path and make the previous sub path current }
    procedure Remove;
    { Close the current path and begin a new empty sub path }
    procedure Close;
    { Join previous path data to the end of the sub paths }
    procedure Join(Path: IPathData);
    { Clip all rendering by the path and remove all path data }
    procedure Clip;
    { Remove any existing clipping paths }
    procedure Unclip;
  end;