[cairo] Size of PDF when splitting a PDF surface

[Chris Wilson]

On Wed, 18 Aug 2010 10:29:52 +0200, Thomas Petazzoni <thomas.petazzoni at enix.org> wrote:
> Is our way of extracting parts of a surface into another surface
> incorrect ? Is there a way of making sure that Cairo includes only once
> in the final PDF the contents of the original surface ?

The way you are generating the split PDF is valid, just Cairo is very
conservative in what it discards. Currently it doesn't do any culling on
the input geometry, though the mechanism are now in place that we could
easily enable culling of operations that only affect areas outside of the
PDF page boundaries. If you want to look for yourself, all one needs to do
is hook up the PDF draw routines to cairo_composite_rectangles_init*() and
return early if those routines indicate that the operation has zero ink
extents.

-- 
Chris Wilson, Intel Open Source Technology Centre