From: James W Sager Iii <sager+@andrew.cmu.edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Hotspots and mouse.
Date: Sat,  2 May 1998 22:56:50 -0400
Organization: Junior, MCS Undeclared, Carnegie Mellon, Pittsburgh, PA
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Excerpts from netnews.comp.os.msdos.djgpp: 2-May-98 Hotspots and mouse.
by "Gillepileptic"@not-very 
> I hope someone can help me with Allegro:  I'm hoping to set up hotspots on a
> static screen (no animation at this stage) Pretty basic stuff, just point
> and click to call a function.
> I've already got the bitmap routines sorted, and I'll figure out the mouse
> stuff from the docs.
> I'd just like to know what's the most flexible and productive way of
> checking whether a mouse has clicked a 'hotspot'?  My program probably only
> needs "...if(((x>100) && (x<120)) &&... " etc, but this seems pretty
> hackish.

Thats exactly how you do it :)
Its quite easy.  The most important thing to remember is
to store
int x=mouse_x;
int y=mouse_y;
int b=mouse_b;

whenever you want to check a certain click.

Then do all your checking from these integers.
If you continually poll the mouse variables
you let yourself up to get weird unreproducable bugs.

Ie if mouse_x is in range(x>20 and x<40)
do some stuff and then
do something based on mouse_x.  It is wrong to
assume that mouse_x will still be in the range of 20,40