^image.circle(center x;center y;radius;line color)
The method draws an unfilled circle of a specified radius, outlined with given color, relative to the center with coordinates X and Y.
Example
$square[^image::create(100;100;0x000000)]
^square.circle(50;50;10;0xFFFFFF)
$response:body[^square.gif[]]
Browser will display a black square with a circle of 10 pixels radius drawn by a line with (50;50) as a center.