At 04:00 AM 3/21/97 -0500, you wrote:
>On Fri, 21 Mar 1997, Stefan Walgenbach wrote:
>Also the colour set it displays in the extended graphics modes seems to
>depend on the phase of the moon. Not for the basic 8 colours, but for
>"mixed" colours made with alternating pixels... something I wouldn't
>normally consider "legal", but for an Apple clone is positivily
>FANTASTIC! :)
The "mixed" colors are created thru a phenomenon called "color
artifacting." This happens when you try to display thin (vertical usually)
white lines on a color TV. The TV cannot show lines that thin on the
phosphor grid, so you end up activating only the (usually) blue or red pixels.
The Color Computer 1 / 2 had the same "problem" and many programs for this
took advantage of this to show color for the highest-resolution which was
monochrome. I think it's the phase of the video sync that changes with
respect to the TV that makes the colors swap... Many of the CoCo programs
that used this technique actually remapped the reset key so it would
re-enter the program, and showed a test screen with 2 boxes and "this
should be blue" under one and "this should be red" under the other. You
just kept resetting the computer (without having to re-load the pgm every
time) until the colors synced correctly. Helpful for RPG's that said "you
need the blue key..."
Of course, when we "geeks" upgraded to the RGB monitor on the CoCo 3, we
lost all color artifacting... and the games became almost totally
unplayable. (No! You need the *other* white-striped key!) ;-)
Roger "Merch" Merchberger
--
Roger Merchberger | Everyone complained to me to change my .sig,
Programmer, NorthernWay | but no-one could recommend something better.
zmerch_at_northernway.net | So you'll have to put up with this *junk*
| until I find some new wisdom to share.
Received on Fri Mar 21 1997 - 08:28:56 GMT