[comp.sys.atari.st] ATARI ST GRAPHICS ?

rthomps@pacsbb.UUCP (Robert Thompson) (07/20/89)

      Atari ST                                 Myarc Geneve
----------------------                   -------------------------
hi  res: 640x400 monocrhome              hi  res: 512x424, 16 colors
med res: 640x200 4 colors                         512x212, 16 colors
                                         med res: 256x212, 256 colors
lo  res: 320x200 16 colors               lo  res: 256x192, 2 of 16 colors
                                                   for each row of 8 pixels
                                                   (TI 99/4A compatible)
text modes: software simulated            text modes: 32x24
                                                      40x24
                                                      80x24
sprites: software simulated               sprites: hardware based,
                                                   multi-colored
hardware graphics:                        hardware graphics:
     *horizontal* lines only                 *all* lines (true?)
                                             multi-colored sprites
                                             pattern fill
The ST uses a display generator           The Geneve has a dedicated (and
chip to draw the screen from part         VERY powerful) graphics chip
of CPU ram, but the generator has         which draws the screen from
no other special abilities.               dedicated video RAM (fast,
                                          auto-incrementing addressing),
                                          in addition to providing many
                                          other useful services.  The
                                          Geneve also has a custom 98 pin
                                          chip which (among other things)
                                          provides a very nice interface
                                          between CPU and video processor.

wsflinn@watcgl.waterloo.edu (Scott Flinn) (07/25/89)

I don't know why ST'ers would be interested in the Myarc Geneve 9640
(a "second generation, much improved TI-99/4A"), but the following
article nonetheless appeared here recently.  Mr. Thompson is not
actually the original author ... this article (quoted in entirety)
was extracted from a larger article posted by me to comp.sys.ti.

My guess is that Mr. Thompson was enraged at finding what he believed
to be a biased article slandering the ST (this is a *guess*), and that
he was posting the article here so that other ST'ers could become
equally enraged and defend the Atari.  I am posting here rather than
replying directly to give people an opportunity to do just that ... I
onw (and love) a 1040ST, and wouldn't want to spread bad rumors about
it.

However, two things should be noted.  Firstly, I very carefully stated
that, with the Blitter chip (not available to most 1040 owners), the
Atari is capable of better graphics performance, and that tricky
techniques could also enhance resolution and colour content tremendously,
but that these programming techniques were not available to Most Normal
People.  These comments were not quoted.

What really bothers me, however, is that
   1)  no credit was given for the quoted article, and 
   2)  the first three lines in the Myarc Geneve column were
       very carefully edited to reduce the apparent ability
       of the Geneve.  If my facts were wrong (they were taken
       from the technical manual which was shipped with my
       Geneve), Mr. Thompson should have explicitly corrected me.
       I have included the original lines (also taken from the
       comp.sys.ti posting) for comparison.

In article <664@pacsbb.UUCP> rthomps@pacsbb.UUCP (Robert  Thompson) writes:
>
>      Atari ST                                 Myarc Geneve
>----------------------                   -------------------------
>hi  res: 640x400 monocrhome              hi  res: 512x424, 16 colors
>med res: 640x200 4 colors                         512x212, 16 colors
>                                         med res: 256x212, 256 colors
>lo  res: 320x200 16 colors               lo  res: 256x192, 2 of 16 colors
>                                                   for each row of 8 pixels
>                                                   (TI 99/4A compatible)
>text modes: software simulated            text modes: 32x24
>                                                      40x24
>                                                      80x24
>sprites: software simulated               sprites: hardware based,
>                                                   multi-colored
>hardware graphics:                        hardware graphics:
>     *horizontal* lines only                 *all* lines (true?)
>                                             multi-colored sprites
>                                             pattern fill
>The ST uses a display generator           The Geneve has a dedicated (and
>chip to draw the screen from part         VERY powerful) graphics chip
>of CPU ram, but the generator has         which draws the screen from
>no other special abilities.               dedicated video RAM (fast,
>                                          auto-incrementing addressing),
>                                          in addition to providing many
>                                          other useful services.  The
>                                          Geneve also has a custom 98 pin
>                                          chip which (among other things)
>                                          provides a very nice interface
>                                          between CPU and video processor.


The first eight lines *should* read:

      Atari ST                                    Myarc Geneve
----------------------                      -------------------------
hi  res: 640x400 monocrhome                  hi  res: 512x424, 16 colours
med res: 640x200 4 colours                   med res: 256x424, 256 colours
						  or  512x212, 256 colours
lo  res: 320x200 16 colours                  lo  res: 256x192, 2 of 16 colours
						      for each row of 8 pixels
						      (TI 99/4A compatible)

Cheers,
-- 
Me:      Scott Flinn                   /  "If it doesn't fit, force it.
Domain:  wsflinn@watcgl.waterloo.edu  /  If it breaks, then it didn't
UUCP:    watmath!watcgl!wsflinn      /  fit anyway."