PANGO_ATTR_SHAPE. See PangoCairoShapeRendererFunc for
details.pangoCairoContextSetShapeRenderer(object, func, data)objectPangoContext] a PangoContext, from a pangocairo font mapfuncPangoCairoShapeRendererFunc] Callback function for rendering attributes of type
PANGO_ATTR_SHAPE, or NULL to disable shape rendering.datafunc.