Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!aplcen!samsung!brutus.cs.uiuc.edu!jarthur!bridge2!3comvax!tymix!tardis!jms
From: jms@tardis.Tymnet.COM (Joe Smith)
Newsgroups: comp.sys.amiga
Subject: Re: Copper Demos... "D.O.C./Crusade"
Summary: Hidden messages for genlocks
Message-ID: <889@tardis.Tymnet.COM>
Date: 16 Dec 89 21:59:06 GMT
References: <791@mindlink.UUCP>
Reply-To: jms@tardis.Tymnet.COM (Joe Smith)
Organization: BT Tymnet, San Jose, CA
Lines: 56

>In article <5697@uhccux.uhcc.hawaii.edu> olson@uhccux.uhcc.hawaii.edu
>(Todd Olson) writes:
>>The demo you speak of is called D.O.C. and it is also a pirate intro.

When it starts, the Workbench screen shakes like an earthquake.
I found this demo on volume PD14, the "Bonus Disk" from AX (I think it
came from the Amiga Exchange magazine-with-a-disk).

In article <791@mindlink.UUCP> a218@mindlink.UUCP (Charlie Gibbs) writes:
>     I have a disk with some demos from German crackers, and this
>sounds like the one in the file named "Crusade".  It consists of a
>number of reflective balls moving in complex patterns on the screen;
>sometimes the balls turn into winged demons.  

Most of the time it is a pattern based on a pentagram (5 pointed star).
The balls have reflective patterns like red marbles, except that they
are not transparent.  They sometime split into 9 smaller balls in
addition to the demons.  Some of the animation is incomplete at the top
of the screen, when the Blitter isn't fast enough to put all the objects
on the screen before the video beam arrives.

>The background consists
>of a checkerboard plain continuously moving off toward the horizon,
>and a backdrop of stars and the letters DOC in some sort of Old
>English font.  At the top of the screen are four horizontal columns
>rotating around each other; bands of colour move up and down them in
>a way which suggests that they are reading out the sound level on
>the audio channels.

There is a hidden message in the upper left hand corner that is visible only
while using a genlock.  It says:

	X-SPEED = 001		(These numbers change as it
	Y-SPEED = 1FE		 cycles through the various
	NEXT-X  = 032		 patterns.)
	NEXT-Y  = 033
	-------------
	  CODING BY
	  UNKNOWN OF
	   D.O.C.

It appears that all of the sky in the background is color zero, and the copper
is used to change it from black at the top of the screen to blue near the
horizon.  The text mentioned above is rendered in different color number
but the two colors always have the same RGB values to they look the same.
That is, until a video signal it applied to the input of the genlock.
At that time, most of the sky (color zero) becomes transparent, and the
text is opaque black and dark blue.  On my system, the text is readable
even though the screen rolls slowly.  The demo has taken over the machine
so that it ignores vertical sync.  (Either that, or it is stable only with
a PAL genlock.)
-- 
Joe Smith (408)922-6220 | SMTP: JMS@F74.TYMNET.COM or jms@gemini.tymnet.com
BT Tymnet Tech Services | UUCP: ...!{ames,pyramid}!oliveb!tymix!tardis!jms
PO Box 49019, MS-D21    | PDP-10 support: My car's license plate is "POPJ P,"
San Jose, CA 95161-9019 | humorous dislaimer: "My Amiga speaks for me."