( resource im, bool on )
Activate the fast drawing antialiased methods for lines and wired polygons.
It does not support alpha components. It works using a direct blend
operation. It works only with truecolor images.
Thickness and styled are not supported.
Using antialiased primitives with transparent background color can end with
some unexpected results. The blend method uses the background color as any
other colors. The lack of alpha component support does not allow an alpha
based antialiasing method.
Note: This function is only available if
PHP is compiled with the bundled version of the GD library.
See also imagecreatetruecolor().