Set the antialiasing mode of the rasterizer used for drawing shapes.
The antialias parameter can be one of the following constants:
#CAIRO_ANTIALIAS_DEFAULT-
Use the default antialiasing for the subsystem and target device.
#CAIRO_ANTIALIAS_NONE-
Use a bilevel alpha mask.
#CAIRO_ANTIALIAS_GRAY-
Perform single-color antialiasing (using shades of gray for black text on a white background, for example).
#CAIRO_ANTIALIAS_SUBPIXEL-
Perform antialiasing by taking advantage of the order of subpixel elements on devices such as LCD panels.
#CAIRO_ANTIALIAS_FAST-
Hint that the backend should perform some antialiasing but prefer speed over quality.
#CAIRO_ANTIALIAS_GOOD-
The backend should balance quality against performance.
#CAIRO_ANTIALIAS_BEST-
Hint that the backend should render at the highest quality, sacrificing speed if necessary.
Note that the antialias value is a hint, and a particular backend may or may not support
a particular value. At the current time, no backend supports #CAIRO_ANTIALIAS_SUBPIXEL when drawing
shapes.
Note that this option does not affect text rendering, instead see
cfontoptions:SetAntialias().