Mark Vojkovich <[EMAIL PROTECTED]> wrote:

>    What are you guys talking about?  XAA already has hooks all over
> the place.

Yes, it does! Now that I am learning more about this I am happy to see 
that someone saw fit to make it so XAA drivers can hook stuff at many 
levels. Very cool. It should be better documented though ;-)

>    XAA already does this!!!  XAA has never cached glyphs in video ram.

Hmm, then how come in the XAA driver architecture there are methods to do 
mono blits from offscreen video memory? I just assumed that this meant 
the glyphs were being cached in offscreen video memory, but perhaps XAA 
is just using offscreen memory as a temporary 'ping ping' buffer in this 
case? Ie: for hardware that can't do system blits but can do blits from 
offscreen video memory?

> > Granted, if you have hardware alpha blits that will be the fastest way to 
> > do this. But if you don't have hardware alpha blits (and lots of cards 
> > supported by XFree86 do not), you can still speed up anti-aliased text 
> > quite a lot by using a 4 or 8 level scheme using multiple mono bitmaps.
> 
>    No you can't.  This text is ALPHA BLENDED into whatever the
> background is.  It is not text "ImageText" - ie. it is not an alpha
> blended string on top of a solid backing rectangle. 

True. The way we implement in our library is that the core of the text 
glyphs (ie: the non-blended solid pixels) are drawn with a fast mono 
blit. Then we render the 4 levels of aliasing into the framebuffer with 
high speed software blending only for the pixels that need to be drawn 
(usually only 5% coverage for a typical sized glyph). Doing it that way 
is still *way* faster than drawing the entire glyph with software 
blending if you don't have hardware compositing.

Regards,

---
Kendall Bennett
Chief Executive Officer
SciTech Software, Inc.
Phone: (530) 894 8400
http://www.scitechsoft.com

~ SciTech SNAP - The future of device driver technology! ~

_______________________________________________
Devel mailing list
[EMAIL PROTECTED]
http://XFree86.Org/mailman/listinfo/devel

Reply via email to