(PHP 5 <= 5.3.0, PECL ming SVN)
SWFShape::drawCurveTo — Draws a curve
$controlx
   , float $controly
   , float $anchorx
   , float $anchory
   [, float $targetx
   ], float $targety
   )This function is EXPERIMENTAL. The behaviour of this function, its name, and surrounding documentation may change without notice in a future release of PHP. This function should be used at your own risk.
   swfshape::drawcurveto() draws a quadratic curve 
   (using the current line style, set by swfshape::setline())
   from the current pen position to 
   (anchorx,anchory) 
   using (controlx,controly)
   as a control point. That is, head towards the control point, 
   then smoothly turn to the anchor point.
  
   With 6 parameters, it draws a cubic bezier to point
   (targetx, targety)
   with control points (controlx,
   controly) and
   (anchorx, anchory).