void addEntry(float ratio,
This function is EXPERIMENTAL. The behaviour of this function, the name of this function, and anything else documented about this function may change without notice in a future release of PHP. Use this function at your own risk.
swfgradient->addentry() adds an entry to the gradient list. ratio is a number between 0 and 1 indicating where in the gradient this color appears. Thou shalt add entries in order of increasing ratio.
red, green, blue is a color (RGB mode). Last parameter a is optional.