From:	Damian Yerrick <MYNAMEISd_yerrick AT hotmail DOT comNO2CANNEDHAM>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Global variables and structs?
Organization:	Pin Eight Software http://pineight.8m.com/
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Date:	Wed, 16 Feb 2000 08:00:04 GMT
To:	djgpp AT delorie DOT com
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On Tue, 15 Feb 2000 21:10:25 -0600, "William J. Urban II"
<wjurban AT tca DOT net> wrote:

>Hello all,
>    Well I am in a C++ class and also teaching myself some simple 2d game
>writing with allegro.  Now, in class we learned about Global variables and
>how we should use them sparingly.  My question is why?

It limits code reusability by causing potential namespace collisions.
It limits stability by giving everything access to everything.

>I have a small move
>the sprite around the screen program and every time I call the function to
>update the screen I have to pass about 8 parameters.  I am thinking of
>rewriting this tonight with global variables so that I dont have to keep
>passing every single parameter.  Any thoughts on this?  Now I can understand
>if its a variable like x but when its something specific that I wont use as
>another variable like mapLocX than I don't understand why I shouldn't make
>it global.  Thanks in advance.

Do it with structs.  Then you can pass a pointer to the struct and to
the screen and be done with it.

-- 
Damian Yerrick  http://yerricde.tripod.com/
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