[Nouveau] [Bug 91056] The Bard's Tale (2005, native) has rendering issues

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=91056

--- Comment #5 from Ilia Mirkin <imirkin at alum.mit.edu> ---
(In reply to Ilia Mirkin from comment #4)
> Created attachment 116707 [details] [review]
> provisional fix
> 
> OK, so this patch appears to fix it. The shaders at the end of that opt
> trace have
> 
> 00000028: b5000409 08000780     add rn f32 $r2 $r2 neg c0[$a1]
> 00000040: b500060d 08004780     add rn f32 $r3 $r3 neg c0[$a1+0x4]
> 
> etc in them. Which seems innocuous enough, but... something about it is bad.
> Perhaps the neg + indirect. Perhaps just indirect. Perhaps... who knows.
> Needs testing.

uniform vec4 colors[4];
uniform int index;
void main() { gl_FragColor = -vec4(0.2, 0.2, 0.2, 0) - colors[index]; }

generates

00000000: 10002001 2400c780     ld $r0 b32 c0[0x40]
00000008: 100d8009 0be4cccf     mov b32 $r2 0xbe4ccccd
00000010: 00040005 c0000780     shl $a1 $r0 0x4
00000018: b5000401 08000780     add rn f32 $r0 $r2 neg c0[$a1]
00000020: b5000405 08004780     add rn f32 $r1 $r2 neg c0[$a1+0x4]
00000028: b5000409 08008780     add rn f32 $r2 $r2 neg c0[$a1+0x8]
00000030: 1400060d 2400c780     ld $r3 b32 c0[$a1+0xc]

Which works fine. There's something even more subtle going on :(

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/nouveau/attachments/20150630/24a00c2e/attachment.html>