Message-Id:	<199811151151.LAA25454@remus.clara.net>
From:	"Arthur" <arfa AT clara DOT net>
To:	<djgpp AT delorie DOT com>
Subject:	RE: Coding problems from an extreme C newbie...
Date:	Sun, 15 Nov 1998 11:50:36 -0000
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Reply-To:	djgpp AT delorie DOT com

> >You can't use readkey, but if the keyboard handler's installed,
> an external
> >array is used to keep track of key presses. Try this:
> >
> >if(key[KEY_UP]) move_up();
> >if(key[KEY_DOWN]) move_down();
> >..
> >and so on.
>
> Okay, so how would I define the array? (I told you I'm a newbie. :)

You don't have to. It's defined in allegro.h. Just make sure you #include
that.

> >> 2. (a general coding question) How can I return back to a specific
> >> point in a function? (without using GOTO of course. :))
> >
> >The only stylistically acceptable way of doing this is within a
> >for(...;...;...){} loop, a do{}while(); loop, or a while(){};
> loop. Anything
> >else is generally put down to bad structure.
>
> Sorry, misworded question on my part.  It should have read: How can I
> return back to a specific point in a function AFTER calling another
> function?  I.e. main() processes some stuff, calls temp(), then temp()
> processes some more stuff, then returns to a point where it left off
> in main().

That's the normal process:

/* CODE BEGINS HERE */
void temp(void)
{
	printf("Now I'm processing in temp()\n");
}

int main(void)
{
	printf("Processing in main()\n");
	temp();
	printf("Back in main() again\n");
	return 0;
}
/* CODE ENDS HERE */

> >That's a perfectly valid method of doing it. The "dirty
> rectangles" method
> >is sometimes quicker, although it really does depend on what
> your game does.
>
> Allright.  Now can you point me in the direction of some sample dirty
> rectangles code?

Have a look at the Allegro demo game. It's a bit complex. I think there are
some tutorials on dirty rectangles somewhere, but I don't know where.
Anyone?

James Arthur
jaa AT arfa DOT clara DOT net
ICQ#15054819

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