^image.rectangle(x0;y0;x1;y1;line color)
The method draws on an image an unfilled rectangle with specified coordinates and specified line color.
Example $square[^image::create(100;100;0x000000)]
^square.rectangle(5;40;95;60;0xFFFFFF)
$response:body[^square.gif[]]
Browser will display a black 100x100 square with an unfilled 90x20 rectangle with white outline according to the given coordinates.