[numeric] new surface width, in points (1 point == 1/72.0 inch)
height.in.points
[numeric] new surface height, in points (1 point == 1/72.0 inch)
Details
This function should only be called before any drawing operations
have been performed on the current page. The simplest way to do
this is to call this function immediately after creating the
surface or immediately after completing a page with either
cairoShowPage or cairoCopyPage.
Since 1.2