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Re: IIc Demo and screensaver



datawiz wrote:
On Jun 1, 6:16 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:

Although this looks best in color, it is simple and intriguing.
I forget where I found it, but it's called JEWEL:

 5  PRINT  CHR$ (21): REM 40-column mode
 8  HCOLOR= 0
 10  FOR X = 7676 TO 7689: READ A: POKE X,A: NEXT X: DATA
1,0,4,0,18,63,32,100,45,21,54,30,7,0: POKE 232,252: POKE 233,29: HGR2 :
HPLOT 0,0: CALL 62454
 20  HCOLOR=  INT ( RND (1) * 7) + 1: FOR R = 1 TO 99: ROT= 24: SCALE=
R + 12: DRAW 1 AT 140,96: NEXT R
 30  IF  PEEK (49152) < 128 GOTO 20
 40  PRINT  CHR$ (4)"bye"



Pretty cool. This could have made a nice Beagle Bros Two-Liner!

I think it started its life as a two-liner, but I can't remember
where I found it.  ;-)

I've always liked shape tables as a fast way of drawing.  My favorite
shape table is the unit vertical vector.  By setting SCALE and ROT
you can essentially do "turtle graphics" easily.

DRAWing a single dot also provides a hires "SCRN" function, since the
collision counter is set if the screen bit is set.

For the curious and lazy, I made a quick Virtual ][ video--
http://204.16.8.40/other/a2/jewel_apple2.mov

Nice!

My emulator is sped up to 8mhz, as I was testing it side by side on a
real IIc with 8mhz zip chip, just for fun.

That's the way it usually runs on my //e.  ;-)

-michael

NadaNet and AppleCrate II: parallel computing for Apple II computers!
Home page: http://home.comcast.net/~mjmahon

"The wastebasket is our most important design
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