void SWFButton::addShape    ( SWFShape $shape   , int $flags   )

SWFButton::addShapeAdds a shape to a button

shape

An SWFShape instance

flags

The following flags are valid: SWFBUTTON_UP, SWFBUTTON_OVER, SWFBUTTON_DOWN and SWFBUTTON_HIT.

SWFBUTTON_HIT isn't ever displayed, it defines the hit region for the button. That is, everywhere the hit shape would be drawn is considered a "touchable" part of the button.