From:	Erik Max Francis <max AT alcyone DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Allegro, pointers : how do I get line from BITMAP?
Date:	Fri, 01 Jan 1999 02:58:48 -0800
Organization:	Alcyone Systems
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To:	djgpp AT delorie DOT com
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"Mikko V.I. Parviainen" wrote:

>   b->line[y][x]
> 
> Functions well. However, the eight indirections (?) of b
> for every cell do add significant overhead, so I tried to
> use an alias for b->line, but could not define the
> variable.

What?  I see only three here.

> In other words, I am trying to define a variable so that
> I could say
> 
>   temp[y][x]     to access      b->line[y][x]
> 
> but cannot find the right expression for temp.
> 
> If you could point me to the right declaration (or some
> other solution), I would be mostly thankful.

Talking generally (I'm not terribly familiar with Allegro), it sounds
like what you want is a "pointer to a structure member," which is not
possible in C.  In C++ you have pointers to class members, but you still
have to reference the class instance when dereferencing them, so that
won't do you any good.

Define a macro if it's really bothering you.

-- 
Erik Max Francis / email max AT alcyone DOT com / whois mf303 / icq 16063900
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