I had to follow your link and so some research, for I didn’t know of this Nintendo gadget from the 90’s — probably, it never made it to the Italian market. It’s difficult to imagine how it the 3D experience could be, since it uses a strange technology of a vibrating mirror to spread a beam of “pixels” vertically across the eyes. Also, the single red color is difficult to imagine. I guess it must be somewhat close to the View Master, but with motion.
My general experience with VR headsets is not positive though, and what I liked of the View Master was exactly that they were still images. Even in VR headets, I preferr games that don’t move at all (e.g. pinball tables), because motion tends to “normalize away” the 3D effect after a while — the same goes with 3D movies using polarized lenses. The fact is that seeing in 3D is the normal condition of mankind, so when we watch a 3D animation we only get that “woow” experience the first 10 minutes, then we focus on the story/game and stereoscopy goes in the background, almost unnoticed.
This is why good 3D animation movies tend to alternate scenes with little movement to sequences with rapid movements and great depth (jumps from buildings, canyons, etc.), because it king of awakes again the awareness that there is a 3D depth in the movie.
Static images/games, on the other hand (like the View Master) give you to chance to focus on the single scene and appreciate its 3 dimensions more (IMO).
As for the technical questions. No, you don’t need depth maps at all, just noise and grain that adds depth. Even in the PS4 VR games you’ll always see that kind of noise — like if there were millions of dust particles in the air. You notice that especially when there is a black scene, because the noise is like many little snowflakes slightly illumintated. That noise is constantly added to the scene to guide the 3D vision, because flat colors and surfaces tend to look as empty holes in stereoscopy.
I’ll give you a link to a few examples — a 3D (anaglyph) website I had created in the early 90s:
(you can also see my stereo camera, the “FED Stereo”, Ukrainian edition) and a photograph I shot with it, rendered in anaglyph via Photoshop — v4 probably!)
Bare in mind that these images are from the era of modem connection to the Internet, and graphics were kept very low due to slowness of the Internet, and that displays were usually 800x600. In fact, this page (full 3D) needs to be scaled to 60% to render properly, because today we have displays double that resolution:
But even if you scale the page in the browser, the 3D effect is preserved — thanks to the noise filters that I’ve added to both color channels. I can’t remember now if I had applied those noise filters on a per layer basis or on the merged final layer. I think that I would use different techniques depending on the image at hand.
The same rules applies to the Nintendo Virtual Boy, no doubt. On Wikipedia it mentions that VB vr32 didn’t use many monocular cues except parallax, which could be one of the main reasons it didn’t take of well:
If you look at the Mario tennis demo, it’s basically very bright thick lines on black baground, which is counterproductive. On the site you linked, modern games for this console tend to use more dithering techiniques to achieve depth — i.e. noise. Dithering is noise, and duotone patterns (like in manga comics) were also used a lot in anaglyph comics to prevent uniform backgrounds from showing up as “empty space”.
With the VB vr32 the big limit is the reduced colors set — 3 shades of red + black. So dithering is a necessity:
But dithering is also good because it preserves 3D depth illusion. I think that on a resolution like this (224 horizontal) it might be difficult to handle noise with just three shades; I mean algorithmically, so you’ll have to work on dithering manually — which doesn’t solve the problem of scaling images down though.
You could try to overlay diagonal lines that cross the “screen” to create an interference pattern that isn’t disrupting. A bit like those filters that emulate CRT monitors on modern computers, by adding horizontal scan lines (again, done via shaders). Diagonal lines (pixel perfect) that somehow affect the hues of the underlying pixel, should create a subtle effect that doesn’t break the image, but you can perceive the diagonal lines. These are like a single duotone noise used in comics — e.g. see this 3D comic:
you can see the duotone patterns on the car seat, and the diagonal lines in the background. Without these reference patterns, the image would look flat with the glasses on.
I hope this might help.
As for the 3D Tv, I don’t think I’ll ever be able to hook it up. It’s too big the screen, and I’d have to be sitting too far away to use it with a PC. The best I could do is put some images on a pen drive and view them with the image apps of the Tv. Regarding the cross-eyes techique, I actually like it — both for stereograms and stereo-photos like these:
(I can see them perfectly without getting fatigued at all).