Comment=
# 5
on bug 89156<=
/a>
from Marek Ol=C5=A1=C3=A1k
(In reply to Stefan D=C3=B6singer from comment #4)
> Created attachment 113841 [details]
> Shader used to read the texture
>=20
> Indeed changing the swizzle fixes the random output. I have attached t=
he
> shader we use to sample the texture. We don't have a swizzle on the
> texture2D statement, but we do swizzle the output variable, and appare=
ntly
> the optimizer merges that.
So it's a compiler bug.
>=20
> If I use the RGBA values returned by the texture sampling directly I g=
et a
> solid color as expected. However, the value is off quite a bit: Instea=
d of
> 0x7f I get 0x6c.
>=20
> The texture data we use is this:
>=20
> static const char ati1n_data[] =3D
> {
> /* A 4x4 texture with the color component at 50%. */
> 0x7f, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> };
That's expected. ATI1N operates at lower precision. I'm afraid I can't chan=
ge
that.