A #cairo_font_face_t specifies all aspects of a font other than the size or font matrix (a font matrix is used to distort a font by shearing it or scaling it unequally in the two directions) . A font face can be set on a #cairo_t by using cairo.context.Context.setFontFace; the size and font matrix are set with cairo.context.Context.setFontSize and cairo.context.Context.setFontMatrix.