PONG - THE AUDIO GAME

	This is a 1- or 2-player game, which uses the bat ranging
circuit for the controllers (designed into ping-pong paddles), and
an audio motion object circuit with headphones.  There would be a
very small ping-pong looking table (foosball sized or smaller), with the
paddles on relatively short and destruction-resistant cables.  At the
beginning of the game the players are given various choices by voice
synthesis.  Choices such as difficulty of game and headphone loudness 
are made by raising and lowering the paddles. 

	1) Type of game

		A.) Competitive ping-pong
		B.) Cooperative ping-pong (joint score, object
			being to keep the ball in play for as long
			as possible)
		C.) Juggling? (with 1-4 objects)
		D.) Other variants


	2) Type of motion object

		A) Ping-pong ball which makes whooshing noise which
			moves spatially to let you know where the
			ball is
		B) Tennis ball
		C) Mack truck
		D) UFO - sci fi
		E) Baby chick (peep peep peep...BGAAAWK...peep peep peep...)
		F) Other objects

	3) Difficulty (speed) of game

		The speed of the game will normally be slower than
			a normal pong game, since it will take longer to
			figure out where the ball is and how it's moving.

	4) Headphone loudness

	5) Other factors (gravity, etc.)

	Once the game choices are made, the game play begins.  The voice will
tell one player to serve.  The game processor must keep track of whether
the paddle hit the ball, and if so, how hard and in what direction.  The
processor won't know how the paddle was angled, so it will assume it was
orthogonal (or whatever) to the ball.  This allows a spin to be put on the
ball, if we want to carry this that far, by hitting the ball while moving
the paddle in a slight sideways direction.  The processor bounces the ball
off the court in 3-d and into the other player's court.  There could be a
small speaker mounted on each paddle, which could make the sound of hitting
the ping-pong ball, to give the players tactile feedback and to entertain
bystanders.  There could also be a speaker on the table, for the bystanders.

	There will be separate sounds for each player when the ball bounces off
a paddle, or bounces off the court, or dribbles to a stop, etc.  There will be
as many subtle audio cues as possible.  The sound of the ball's collision with
the paddle or the court will vary in loudness and brightness depending on the
speed and possibly the angle of the collision.  The pitch of the ball's motion
could have a slight doppler shift depending on velocity.  The critical factor
for game play will be how accurately we can inform the player of the ball's
distance and spatial position while it is in flight.  The main distance cue
is the proportion of direct vs. reverberant sound.  The main left-right cue
will be small time-delays between the left and right channels.  The up-down
cue is the most difficult, as it depends upon differences in frequency response
due to the filtering caused by the shape of the external ear.  Some research
would need to be done to find out how easily this latter effect can be
simulated.

	The audio motion object simulator might consist of the following:

	1) One or more Yamaha sound chips

	2) Delay controller, which would preferably be 1 or more
		microprocessors (6502), if speed constraints allow.
		The controller would keep track of where the RAM delay
		pointers are, read in and scale data from
		various locations, add it together, and save it to
		another location, depending on left-right time delay,
		percentage of direct and reverberant sound, and
		percentage of filtered sound.
		
	3) A RAM (on the order of 10K words.)

	4) A DAC, analog multiplexer, (processor-controlled) lowpass
		filters, and A-D's for doing the frequency-response up-down
		cuing.  This would ideally be done in software if we had
		something fast enough to do it.  Alternatively, we could
		skip the up-down cuing simulation and just raise and
		lower the frequency of the ball to indicate where it is
		vertically.  But the realism would be lost.  Another
		possibility is changing Yamaha parameters in real time to
		correspond to the change in frequency response between
		up and down.  This is the section for which much research
		must be done.

	5) Quality low-pass filters for the output.


	This circuit will be somewhat expensive, but there is no overhead
for a monitor and video hardware.  Even if some of the audio parameters
are somewhat arbitrary, so long as enough information is present, the
skill may be learnable and perfectible.  The speech synthesis could carry
on a running play-by-play, or could say to each player what the other
player is supposedly saying.  Once the basic game play and motion object
circuitry are designed, many variations can be easily added.

	A similar hardware could be used for a Star Wars type light saber
game.  The player puts on his blast helmet and uses the light saber, with
bat ranging circuit, to battle the floating training orb.