question: public void straight ( double x , double y ) { double dx = x - pen . x ; double dy = y - pen . y ; if ( convertToTwips ) { dx *= SwfConstants . TWIPS_PER_PIXEL ; dy *= SwfConstants . TWIPS_PER_PIXEL ; } if ( dx == 0 && dy == 0 ) { return ; } else { int intdx = ( int ) Math . rint ( dx ) ; int intdy = ( int ) Math . rint ( dy ) ; addLineSubdivideAware ( intdx , intdy ) ; pen . x = x ; pen . y = y ; dxSumTwips += intdx ; dySumTwips += intdy ; } }
target:  Calculates the change or 'delta' in position between the current pen location and a given co-ordinate pair. This delta is used to create a straight-edge shape record in SWF, i.e. a simple line.