Re: [Qemu-devel] [PATCH 1/3] Fix SDL problems with BGR displays

["Blue Swirl" <blauwirbel@gmail.com>]

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On 7/23/08, Blue Swirl <blauwirbel@gmail.com> wrote:
> On 7/23/08, Anthony Liguori <aliguori@us.ibm.com> wrote:
>  > Andreas Färber wrote:
>  >
>  > > Hi,
>  > >
>  > > Am 22.07.2008 um 22:51 schrieb Anthony Liguori:
>  > >
>  > >
>  > > > From: Avi Kivity <avi@qumranet.com>
>  > > >
>  > > > kvm: qemu: revert qemu's sdl.c rev 1.40
>  > > >
>  > > > this fixes problems with bgr displays.
>  > > >
>  > >
>  > > What problems exactly are you fixing? Could other backends such as Cocoa
>  > be affected, too?
>  > >
>  >
>  >  The original commit in question is 2974.  I don't have the ability to test
>  > Cocoa but we received a bug report about a BGR display regression shortly
>  > after this commit.  Reverting this particular part of the commit made the
>  > problem go away.  See
>  > http://thread.gmane.org/gmane.comp.emulators.kvm.devel/7773
>  >
>  >  Perhaps Blue Swirl can comment if reverting this part of the patch
>  > regresses some of the test cases he was working with when he committed the
>  > original patch?
>
>
> I can't reproduce the problem anymore, even reverting the patch
>  changes nothing at depth 16. There seems to be other bugs involved,
>  for example at depth 15 everything looks cosmic. Maybe VGA memory
>  accesses assume some host endianness which are wrong on big endian
>  host.
>

This patch gets 15 bit display working for me. SDL BitsPerPixel never
indicates any values other than multiples of 8, so we need to check
for strange depths. Any comments?

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