[Xorg-driver-geode] Glyph rendering

[Jonathan Morton]

On 19 July 2010 12:35, Huang, FrankR <FrankR.Huang at amd.com> wrote:
> I found that our HW can not support PICT_a8 destination, only support PICT_r3g3b2 destination. Can you use PICT_r3g3b2? From the experiment, the result is not correct. I think the HW will split the 8 bits value into 3,3,2 and do the PictOpAdd separately instead a whole 8 bits value?
> Or do that in SW way (I wrote in the driver)?

You have better information on the hardware than I do.  I can only
tell you what needs to be done.

For this particular purpose you can treat A8 as being equivalt to
8-bit greyscale.  I don't know if that helps you.

If there is no way to make Geode do the A8 addition in one pass, then
it is probably better to do it in software.  This is trivially
achieved by rejecting the operation and allowing Pixman to take it
over.  Pixman - if a recent enough version - will automatically take
advantage of MMX or SSE2 if available (I don't know if your hardware
has it).

 - Jonathan Morton