From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Alpha Blend Table or Assembly
Date:	11 Apr 2001 12:10:14 GMT
Organization:	Aachen University of Technology (RWTH)
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Sahab Yazdani <sahaby AT operamail DOT com> wrote:
> okay, I want to write a function that performs Alpha Blending between 
> the backdrop and a bitmap being blitted.
> I can think of two ways of doing this... create a 64K (256*256) alpha 
> blend table and use this in a C function (should be pretty quick) or 
> write it in Assembly (this will be harder cuz my knowledge of Assembly 
> ain't that great).

With all due respect: if you're not quite good at assembly, don't
bother trying to beat GCC --- you won't manage, and only waste your
time and effort.

> if the second option is better (assembly), then I would like to know how 
> to make GCC output assembly code (i think borland C did this at one 
> point).  And then I will try to optimize the outputed assembly code...

gcc -S instead of gcc -c gives you assembly output. For additional
information in the assembly, you may want to use gcc -S -g3
-fverbose-asm.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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