Re: Vector Emulation

Im not sure how it is done but the Geiss visual plug-in for WinAmp has line graphics
(albeit more complex) that fade almost like a BW vector monitor, quite a bit slower even.
Im not sure if it is done in bitmap RAM or something with the video card, but it looks
nice.

Andrew Wilson wrote:
>
> >I suspect a proper implementation of this would go a long way toward
> >making the B/W vector emulations look better. It doesn't address the
> >trails you leave, but I suspect carefull use of alpha buffers could
> >help (but 8 bits of alpha won't allow much precision in the decay).
> >Hmmm, dump the last N frames into separate buffers and blend according
> >to predefined formula... Hmmm tons of video RAM, but it could be an
> >option for people with SGIs.
>
> Maybe. Or just a single frame buffer whose contents "decay" to black
> over time with a simple pixel op (e.g. start with the last frame's image in
> the frame buffer, reduce it by doing (say) a 30% blend with black, then draw
> the current frame - this would cause lines to fade out over the subsequent 3
> frames). This would seem to more closely model the behavior of real hardware,
> without requiring multiple frame buffers, and I think most 3D cards will do
> a single blend operation quite quickly).
>
> I'd be interested in seeing what the results of that decay + a
> 3D card's built-in anti-aliasing would produce. You could probably do the
> decay in MAME without using a 3D card, just by doing the decay op instead
> of clearing the frame buffer between frames.
>
> Drew
Received on Mon Oct 4 17:51:45 1999