(PECL ps >= 1.1.0)
ps_show_xy — Output text at given position
$psdoc,$text,$x,$yOutput a text at the given text position.
psdocResource identifier of the postscript file as returned by ps_new().
textThe text to be output.
xx-coordinate of the lower left corner of the box surrounding the text.
yy-coordinate of the lower left corner of the box surrounding the text.
成功时返回 true, 或者在失败时返回 false。