Disable npot texture support on AMD cards on XP.

Disable npot texture support on AMD cards on XP.

We had been seeing some BSODs due to this.


BUG=

Committed: https://code.google.com/p/angleproject/source/detail?r=1264

[John Bauman, 2012-08-27 16:13:32]

ping

[dgkoch, 2012-08-27 17:33:52]

The patch seems fine enough from a code POV. But killing NPOT on all AMD cards
on XP seems a bit extreme.  It can't be narrowed down any further?

[John Bauman, 2012-08-27 17:39:26]

On 2012/08/27 17:33:52, dgkoch wrote:
> The patch seems fine enough from a code POV. But killing NPOT on all AMD cards
> on XP seems a bit extreme.  It can't be narrowed down any further?

No, the BSOD can happen on all AMD cards, with any NPOT texture that has more
than 1 miplevel. Chrome doesn't expose this extension to web content (except
through pepper, and that's probably pretty uncommon), so getting rid of it won't
affect us much.

[dgkoch, 2012-08-27 17:42:21]

On 2012/08/27 17:39:26, John Bauman wrote:
> On 2012/08/27 17:33:52, dgkoch wrote:
> > The patch seems fine enough from a code POV. But killing NPOT on all AMD
cards
> > on XP seems a bit extreme.  It can't be narrowed down any further?
> 
> No, the BSOD can happen on all AMD cards, with any NPOT texture that has more
> than 1 miplevel. Chrome doesn't expose this extension to web content (except
> through pepper, and that's probably pretty uncommon), so getting rid of it
won't
> affect us much.

It's not limited to certain drivers either (new/old?).  One would think using
npot textures on d3d9 would be pretty common..

Anyhow LGTM if that's what you need to do.

[John Bauman, 2012-08-27 17:44:34]

On 2012/08/27 17:42:21, dgkoch wrote:
> On 2012/08/27 17:39:26, John Bauman wrote:
> > On 2012/08/27 17:33:52, dgkoch wrote:
> > > The patch seems fine enough from a code POV. But killing NPOT on all AMD
> cards
> > > on XP seems a bit extreme.  It can't be narrowed down any further?
> > 
> > No, the BSOD can happen on all AMD cards, with any NPOT texture that has
more
> > than 1 miplevel. Chrome doesn't expose this extension to web content (except
> > through pepper, and that's probably pretty uncommon), so getting rid of it
> won't
> > affect us much.
> 
> It's not limited to certain drivers either (new/old?).  One would think using
> npot textures on d3d9 would be pretty common..

Every driver version we know of has the bug. I'm not sure how common NPOT
textures with multiple miplevels are, but maybe our specific usecase makes us
somewhat more likely to hit the bug than otherwise.
> 
> Anyhow LGTM if that's what you need to do.