(No version information available, might only be in SVN)
Specifies the type of hinting to do on font outlines. Hinting is the process of fitting outlines to the pixel grid in order to improve the appearance of the result. Since hinting outlines involves distorting them, it also reduces the faithfulness to the original outline shapes. Not all of the outline hinting styles are supported by all font backends.
CairoHintStyle::STYLE_DEFAULT
     Use the default hint style for font backend and target device
CairoHintStyle::STYLE_NONE
     Do not hint outlines
CairoHintStyle::STYLE_SLIGHT
     Hint outlines slightly to improve contrast while retaining good fidelity to the original shapes.
CairoHintStyle::STYLE_MEDIUM
     Hint outlines with medium strength giving a compromise between fidelity to the original shapes and contrast
CairoHintStyle::STYLE_FULL
     Hint outlines to maximize contrast