[cairo] Overflow bug painting from PixBuf?

[Chris Wilson]

Excerpts from Arjen Nienhuis's message of Thu Oct 15 00:24:14 +0100 2009:
> I'm using cairo 1.8.8 and python to create some png files.

[snip]

> This works fine until dst_x / scale > 32000. Then garbage is copied to
> ctx. This also occurs with the PDF backend.
> 
> This means I cannot put a small thumbnail on the right side of an
> image. (see attachment, the last photo is missing)
> 
> Is this a known bug? Is there anything I can do? Pre-scaling the
> pixbuf might work.

It is a known bug, a limitation of the fixed-point 16.16 matrix that we
use to transform images with pixman. In cairo-1.9.2, we have a
workaround that takes advantage of the fact that we can do the
translation independently of the matrix that extends our operating range
a bit (but still leaves worse than desired inaccuracies). In short, try
1.9.2, it's probably good enough for the task at hand.

Hope this helps, and you have fun with cairo!
-ickle
-- 
Chris Wilson, Intel Open Source Technology Centre