(PECL ps:1.1.0-1.3.5)
ps_arcn — Draws an arc clockwise
Draws a portion of a circle with at middle point at (x , y ). The arc starts at an angle of alpha and ends at an angle of beta . It is drawn clockwise (use ps_arc() to draw counterclockwise). The subpath added to the current path starts on the arc at angle beta and ends on the arc at angle alpha .
Resource identifier of the postscript file as returned by ps_new().
The x-coordinate of the circle's middle point.
The y-coordinate of the circle's middle point.
The radius of the circle
The starting angle given in degrees.
The end angle given in degrees.
如果成功则返回 TRUE，失败则返回 FALSE。