[PATCH 1/3] wined3d: Don't shift geometry for d3d10/11.

Stefan Dösinger stefan at codeweavers.com
Thu Aug 12 15:01:56 CDT 2021

Am Donnerstag, 12. August 2021, 20:32:22 EAT schrieb Henri Verbeet:

> Perhaps Windows imposes additional restrictions on GL, but as far as
> I'm aware the only thing the GL spec requires in this regard is the
> following:
> <snip>

Ya, makes a lot more sense now why we have the x nudge too.

> Are we using shader offsets or ARB_clip_control/viewport offsets in
> the broken case? I wouldn't be entirely surprised if some drivers
> don't handle fractional viewport offsets entirely correctly. If
> possible, it may be worth trying to switch to the shader offset
> implementation to see if it makes any difference. Is there any
> multi-sampling or sample shading involved?

I haven't made much sense of it yet. I tested both ways of applying the offset, 
so far I can't tell a difference. That said, on MacOS we disable clip_control 
because our test that checks for broken fractional viewport offset fails. (I 
think; I have to re-check why we don't have clip control, but for whatever 
reason, we don't have clip control on mac). Forcing clip control off on Linux 
doesn't break the game.

> Note that I don't personally remember the Spore bug being about the
> filling convention; I remember the bug, but if you told me it was
> about the half-pixel offset instead I'd believe you.

It was both, I think. The way I remember it (and it's 13 years ago, so I might 
remember wrong): It used to work on Geforce 7 cards (and probably r500), but 
was broken on Geforce 8 cards. You added the half pixel offset thing to fix it 
(or added it for offscreen rendering, or something). That fixed it on geforce 8, 
but broke it on geforce 7. Adding the nudge some time later fixed it on both, 
or so we thought: https://bugs.winehq.org/show_bug.cgi?id=43708 says it still 
happens somewhere.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: This is a digitally signed message part.
URL: <http://www.winehq.org/pipermail/wine-devel/attachments/20210812/3dd8cb95/attachment.sig>

More information about the wine-devel mailing list