Re: [gtk-vnc-devel] Fix pixel shift for BGR format servers

["Daniel P. Berrange" <berrange redhat com>]

On Tue, Jul 10, 2007 at 10:15:44PM +0100, Daniel P. Berrange wrote:
> The code which currently calculates the pixel shift for converting data
> from remote to local encoding is assuming the server is in RGB format
> pixels. If I run a server in BGR format, then the colours are rather
> messed up. I've attached a patch which tries to correct it - although its
> not perfect because now, the code assume either RGB, or BGR - is it possible
> for a server to use GRB, or GBR ?!?!  If not then this may be sufficient.
> 
> I'm also not entirely convinced this is correct wrt to local server
> format, eg if your local desktop ran in BGR instead of RGB. I don't have
> any system I can make run in BGR locally though, so can't test.

Hmm, well for the local server, it turns out this question is totally
academic. GTK / Cairo  crash & burn if you try to run them in a BGR
pixel format

Error: Cairo does not yet support the requested image format:
        Depth: 16
        Alpha mask: 0x00000000
        Red   mask: 0x0000001f
        Green mask: 0x000007e0
        Blue  mask: 0x0000f800
Please file an enhacement request (quoting the above) at:
http://bugs.freedesktop.org/enter_bug.cgi?product=cairo
gnome_segv: cairo-image-surface.c:155: _cairo_format_from_pixman_format: Assertion `NOT_REACHED' failed.


So, merely being able to handle BGR from the remote server is sufficient
for now.

Dan.
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