Date: Thu, 17 Feb 2000 11:56:31 +0600 (LKT) From: Kalum Somaratna aka Grendel X-Sender: root AT darkstar DOT grendel DOT net To: djgpp AT delorie DOT com Subject: Re: Global variables and structs? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Reply-To: djgpp AT delorie DOT com Errors-To: dj-admin AT delorie DOT com X-Mailing-List: djgpp AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk On Wed, 16 Feb 2000, Damian Yerrick wrote: > On Tue, 15 Feb 2000 21:10:25 -0600, "William J. Urban II" > 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. This is true but the calculated use of global variables can help to avoid passing many arguments to functions. So using global variables can help to simplify the code and also make it easier to understand. But IMHO this should be done if you are confident with C/C++. > > >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. Or better still use a global struct. That way you won't have to pass anything at all and it will make writing the code easier. HTH, Kalum > > This is McAfee VirusScan. Add these two lines to your .sig to > prevent the spread of .sig viruses. http://www.mcafee.com/ ^^^^ Guess this "virus scan" is not working eh.... Hi, I'm a signature virus. plz set me as your signature and help me spread :)