Random VGA question: 160x200 "high color" mode?

Josh Dersch derschjo at gmail.com
Wed Mar 2 23:32:29 CST 2016


On 3/2/16 10:45 AM, ethan at 757.org wrote:
>>> I've tried it on a number of machines (from the 386 era to a modern PC)
>>> and they all just end up showing garbage when this mode is enabled.  I
>>> cannot for the life of me find a reference to this mode existing
>>> anywhere, but I assume it must have worked on *some* SVGA chipset of 
>>> the
>>> era since ID programmed in support for it.  I'm guessing it was cut
>>> because nothing else supported it (and because 160x200 must have looked
>>> awful, even with lots of colors...)
>
> VGA has analog RGB signals.
> VGA card uses DAC chip, 8 bit would give the 256 color and 16 bit 
> would give the 65536, and 24 bit would give the 16.7 million color 
> depth. RAM was a big issue as well on these cards, since more memory 
> needed to store color info.
>
> The one thing I would wonder is -- even if some video card had the 
> ability to sacrifice resolution for color depth (reconfigurable 
> RAMDAC?) -- were the textures and tiles in Doom supplied in true 
> color/16 bit color or were they 256 colors?
The graphics were only 256 colors, but the engine provided for varying 
lighting levels per-sector so having more colors would allow for 
better-looking rendering.

- Josh

>
> -- 
> Ethan O'Toole
>
>



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