for those new this all this, "anchor" is where you want to end up and "control" is the point you would go to if you were drawing a square.
for example, this would draw a quarter circle
$s->drawCurveTo(200, 200, 100, 200);
(PHP 4 >= 4.0.5)
SWFShape::drawCurveTo — Draws a curve
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
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
with control points (