Aqua Demo created by John Enright on 3-13-94.  This
small demo was put together in one afternoon using graphics by Mike Alkan.
Thanks Mike!  Note that all graphics are Copyright (c) Mike Alkan, and are
included with this package by permission.  The graphics are for demo purposes
only, and may not be included in other works.

A few words about the demo:

* Click either mouse button to exit.

* The demo will automatically scroll left & right over a 12K (roughly) virtual
  space area.  "Real space" is only just larger than the actual display.
  Objects in virtual space are not actually drawn by the animation system.

* Move the joystick left or right to scroll faster.  Press the button to hold
  the display still.

* Because of the number of objects moving (or not moving in the case of coral)
  around in virtual space, a faster processor than the 68000 is recommended,
  as without it things can get a little sluggish.

* Watch as creatures move in front of or behind the coral!  Adds a sense of
  depth to the scene.  This shows good use of object prioritization.

* This is not a tilemap scroller, and because of this, you may see some flicker
  when the bitmap is wrapped.  A properly set up tilemap scroller won't have
  this problem.

* This is yet another good example of how to handle full frame rate scrolling
  regardless of how fast objects are moving on the screen.  The interrupt
  driven scrolling routine could just as easily be used to keep a controllable
  character within certain screen bounds (see the MoonRocks demo by Alan Bland
  for an example of this technique).  The scroller itself is quite a bit more
  complex than it would be under a tilemap system, as it tries to predict when
  the bitmap will need to be reset, and get rid of as much flicker as possible.

If you would like to contact Mike Alkan, you may call him at (416) 481-5442.
He lives in Canada.  He is an excellent graphic artist (commercial quality, in
my opinion).

The source code for this demo is hereby placed in the public domain.


                                           -John Enright