(PECL haru >= 0.0.1)
HaruPage::ellipse — Append an ellipse to the current path
$x
   , float $y
   , float $xray
   , float $yray
   )Appends an ellipse to the current path.
x
     Horizontal coordinate of the center.
y
     Vertical coordinate of the center.
xray
     The ray of the ellipse in the x direction.
yray
     The ray of the ellipse in the y direction.
   Returns TRUE on success.
  
发生错误时抛出 HaruException 异常。