On Wed, 18 Aug 2010 10:29:52 +0200, Thomas Petazzoni <[email protected]> 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
