> On Apr 6, 2024, at 11:40 AM, Phil Budne via cctalk <cctalk@classiccmp.org>
> wrote:
>
> Paul Koning wrote:
>
>> Yes, and some emulations have done this, such as Phil Budne's famous work in
>> SIMH.
>
> Famous?? I'm famous???!!!
>
> To be fair, I started with Douglas W. Jones' PDP8 Emulator.
>
> Which reminds me of:
>
> If I have seen farther than others, it is because I was standing on the
> shoulders of giants. -- Isaac Newton
>
> In the sciences, we are now uniquely privileged to sit side by side with
> the giants on whose shoulders we stand. -- Gerald Holton
>
> If I have not seen as far as others, it is because giants were standing on
> my shoulders. -- Hal Abelson
>
> In computer science, we stand on each other's feet. -- Brian K. Reid
Well said, indeed!
> It was certainly an awakening to the inherent parallelism of "analog"
> natural processes... I wrote and tuned the code twenty years ago, but
> haven't looked at whether better results might be possible by wasting
> the capabilities of current systems (SIMD libaries and/or multiple
> cores). I felt like I only was able to give a slim impression, and
> not an immersive experience. I've also wondered what could be done
> with 4K HDR displays: making points round(!) and simulating the
> "bloom" and intensity of repeatedly or highly intensified spots.
I did these things, in an emulation of the CDC 6600 console (DD60). It paints
the "dot" on the screen using a 2D Gaussian distribution around the nominal
center, with its parameters adjusted by the "focus" and "intensity" controls
just like on the original. And each visit of the spot is summed into the
current screen data using saturated arithmetic. So you get intensification at
no extra charge, and if a spot is drawn many times it also gets a bit blurrier
due to the skirts of the Gaussian distribution becoming more visible. At one
point I had the spot as an RGB value with a touch of blue in it, so the "bloom"
would be bluer than normal lines. I took that out because I don't remember
what the real screen actually does. But clearly a color shift like that could
be simulated.
paul
