1190 Albany Avenue
                                                     Brooklyn, New York 11203
                                                     April 26, 1984

THE ARCADIAN
3626 Morrie Drive
San Jose, California 95127
Dear Robert Fabris:

Thank you very much for placing my ads in your journal.  I have enclosed a 
different ad that I can place in the next issue.  This one is a photostat and 
should reduce better.  I have someone working on a better drawing of a cyclops 
and overall appearance of the ad itself.  A smaller size too.

The cassette enclosed has the graphics program Video:Video that the Arcadian is 
welcome to print.  It is basically an extension of Lesson 7 of the manual 6004.  
A different plot formula was used in which X & Y vary.  Very complex patterns 
appear with a value 1 for every value of Z in line 4.  These take a very long 
time to draw so Z varies between 2 and 5.  Another difference is that all lines 
return to 0,0 before being drawn to the opposite end of the screen.

I'll do my best to have another program for you by the end of May.

Sincerely,


Fred Rodney


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"Video:Video" Instructions
By Fred Rodney


This is a graphics only program. No sound. It takes about 16 minutes to run and 
will continually re-cycle itself. So before running this program, turn on the 
radio or put your favorite record on and enjoy the "Video."

On the Astrocade screen, with 0,0, at its center, the formula N=ABS(X)+ABS(Y) 
will result in a diamond whose points will be at a distance of N & -N from 0,0, 
Plotting lines to all pixels between these four points should yield a solid 
diamond. But the Astrocade only draws a straight line when X=Y, X=0 or Y=0. At 
all other times, the line will assume a "stair-case" shape. This shaped line 
will miss some pixels as X & Y vary between N and -N. The line will be a mirror 
image of itself if the vector of the plot is reversed. The pixels that are 
skipped or re-drawn (LINE X,Y,3) result in a top-bottom, right-left symmetrical 
image within a diamond-shaped border.

If N is varied between -130 and 130 (the LINE command is not limited by the 
screen border as is the BOX command) the diamond will completely fill the 
screen. The program begins at this point and a series of lines are drawn to 
every 5th pixel. As N decreases, smaller and smaller diamonds are drawn. These 
alternate with similar patterns. When N=0 a short BOX routine follows. When 
N.<0 lines are drawn to the diamonds border (every other pixel) with a tighter 
spacing alternating with similar patterns. Finally, when N is set to more than 
130, a patterned "X" appears as in Line 13.

Subroutine 5 is a variable delay (varies with pattern size). The bulk of the 
program that remains involves changes to the colors and &(9) so that the 
patterns are highlighted in different ways. The redrawing of a pattern over 
itself (LINE X,Y,3) will erase the pattern line by line.

Save on tape with CLEAR ;G0T0 15 GO. When the corners are filled, start the 
tape (record) and a nice looking title page will be on tape. The program uses 
1005 bytes.

Fred Rodney 1190 Albany Ave. Brooklyn, N.Y. 11203