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Commodore 128's VDC graphics superior to GS VGC graphics?



Is the Commodore 128's graphics chip, the VDC, superior to the
VGC graphics chip of the GS?  I saw this in comp.sys.cbm....

>>>

Subject: Re: What exactly are the C128's graphics capabilities?
From: Nate Dannenberg <natedac@onyx.southwind.net>
Date: Wed, Mar 25, 1998 08:37 EST
Message-id: <Pine.BSI.3.95.980325071255.13510B-100000@onyx.southwind.net>

> What are the Commodore 128's graphics capabilities?  At what
> resolutions and colors....and combinations of the two does the
> 128 operate?

The composite screen is identical to the C64's screen, and includes these
modes among others:

40x25, 16 colors - Standard text mode, what you see when you start in 40
column mode.

160x200, 16 colors - Standard Multicolor Mode bitmap, as found on the 64.
40 column composite display only.

320x200, 16 colors - Standard Hires Bitmap, as found on the 64.  40 column
display only.


And on the 80-column RGBI (CGA compatible) screen:


80x25, 16 colors - Standard text mode, what you see when you start the
machine in 80 column mode.  Standard on all C128's.

80x50, 16 colors - Interlaced text mode, possible even on regular 16K VDC
systems.

Desterm 128 supports other text display modes ranging from 80x23 to 80x64.
In 80x30 mode, some monitors will produce a rolling or jumping picture,
which can be compensated for by adjusting some settings in the program.
Some monitors like the 1902A will automatically resize the screen slightly
to make the full 30 rows visible, thanks to the VDC's higher sync rate in
this mode.

Anything higher than 80x30 requires an interlaced display, which all
C128's are capable of.


The VDC chip supports many graphics modes, most of which are based on the
C64's Hires 320x200 16 color display:

640x200, 2 colors - Double hires mode found in the VDC, similar to the
C64's 320x200 mode, useful for 16K VDC systems (Like the flat 128).  80
column RGBI ("CGA") display only.  Also works on 64K systems of course.
Compare to "Hercules" displau as found on some old PC's.

640x200, 16 colors - same as above, but with the full color palette.  Only
works if you have more than 16K VDC ram.  80 column 64K display only.

640x400, 16 or 136 colors - an interlaced version of the above screen.
You have a true 16 color palette, but the interlacing allows you to mix
colors like you can on a C64 interlaced screen.  80 column 64K display
only.  I-Paint 128 (and it's companion program, I-Port) uses this mode for
very high quality pictures.

640x480, 16 colors - can't say I've seen any program actually use this
display mode, but it's a perfectly valid setting.  it would work like the
other interlaced modes, and is for 80 column 64K displays only.

640x600, 16 or 136 colors - same as above, with more ertical resolution.
80 column 64K display only.  A program called "Disp/Lace" displays SIX C64
"Doodle" pictures at once, using this mode.

720x700, 2 colors - highest resolution monochrome display I've ever seen
the C128 do.  80 column 64K display only.  An unnamed C128 demo that I
have (simply called "Hires VDC Demo" or similar, apparently originally
produced in a German speaking country) uses this display mode for a
couple of the screens.

This mode extends the graphics display beyond the edges of the screen! 
Unlike the 64, the VDC's entire display is directly programmable - the
borders can be removed with a few changes to the VDC registers. 

I would also expect that the VDC can be programmed to produce an 800x600
16 color display, with enough fiddling with the registers.

<<<

With graphics like this, who needs a Second Sight.  Can it really be
that the C128's graphics are superior to the GS?