Graphics implementation on Windows

Andreas Raab raab at isgnw.cs.Uni-Magdeburg.DE
Sun Feb 15 18:41:07 UTC 1998


> Really? Oh goody! The Acorn does the same and it has been driving me
> nuts trying to work out how to deal with it properly. I guess the
> difference that gets you out of trouble on w95 is the ability to specify
> the palette even for 16/32bpp  displays.

Exactly. You specify the palette in terms of r/g/b bit indexes in the
actual color word (it's very much like VWs FixedPalette).

> When I was doing the little endian bitblt I nearly went for making the
> changes to reverse the rgb order but stopped because it looked like the
> pc used same format as mac and I couldn't see wasting the time for only
> the one platform. Now if it turns out that pcs need both little endian
> _and_ reversed rgb, maybe it would be worth it. There is potential for
> some useful performance improvements.

That's not sure. It depends heavily on the graphics drivers -- some of the
more sophisticated ones can actually transform the data during transfer so
you won't have any gain in speed. Also, if you want to go for anything
besides true 24bit display depth you have to support all the variants of
16bit display depths. I'm not really going to implement that (and yes, I
do have a proper graphics driver ;-)

Andreas
-- 
Linear algebra is your friend - Trigonometry is your enemy.
+===== Andreas Raab ============= (raab at isg.cs.uni-magdeburg.de) =====+
I Department of Simulation and Graphics      Phone: +49 391 671 8065  I
I University of Magdeburg, Germany           Fax:   +49 391 671 1164  I
+=============< http://isgwww.cs.uni-magdeburg.de/~raab >=============+





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