Reference TWidgetRectHelper

  TWidgetRectHelper = record helper for TRectF
  public
    { Round the position and size to whole pixels, offset by half a pixel when
      Width is odd so lines of that width are sharp }
    function Round(Width: LongWord = 1): TRectF;
    { Returns a point on the rectangle numbered like a keypad, 1 being the top
      left, 5 the center, and 9 the bottom right }
    function Sector(S: Integer): TPointF;
  end;