On Thu, Mar 20, 2003 at 05:32:04PM +0100, Denis Oliver Kropp wrote:
> Quoting Ville Syrj�l� ([EMAIL PROTECTED]):
> > For palette lookups in the accel code I've used 0x80 as the alpha value 
> > since palette alpha is irrelevant for this format.
> 
> We should add a palette capability if the palette uses the alpha component
> and have a seperate lookup method for palettes without alpha.

Good idea. It would also improve the accuracy of the palette lookup since
the alpha component wouldn't affect the calculations.

But then there's a problem with SetColorIndex() since it can't change the
alpha value. Add a new SetAlpha() method or instruct users to use
SetColor()?

Also I was thinking about using the alpha from the first two palette
entries for c2bpp15lalpha and c2bpp15halpha. These would allow more than
on-off opacity in ARGB1555 mode but only two levels at the same time. I
haven't really tested the sub-picture stuff with CRTC2 in other than
YV12/I420 modes but I think it's only possible to select a color and
opacity. So there's no sub-picture surface only a constant color. There's
a table of acceptable settings in the G400 specs. I'm not sure if anyone
would seriosly want to use this feature.

-- 
Ville Syrj�l�
[EMAIL PROTECTED]
http://www.sci.fi/~syrjala/


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