module Cairo_pdf:PDF backendsig
..end
typesurface =
[ `Any | `PDF ] Cairo.surface
val surface_create_for_channel : Pervasives.out_channel ->
width_in_points:float -> height_in_points:float -> surface
val surface_create_for_stream : (string -> unit) ->
width_in_points:float -> height_in_points:float -> surface
val set_dpi : [> `PDF ] Cairo.surface -> x_dpi:float -> y_dpi:float -> unit