that’s essentially correct, yes, so you’d be looking at n64 (consoles) and nds (handhelds) onward. even then i only said i think it’s possible, to what extent idk. games handle stuff like shadows differently and i’m not sure you could account for things like that by just looking at the commands submitted via the platforms graphics api.
re psx plugins: as i already stated, while i’m not 100% on this, i believe both psx and saturn do not track certain properties for lighting and materials that would be needed to get any kind of benefit. thus even if you did raytrace the scene i don’t think it would look much different than what gpu rasterization gives, just much slower. (and/or you would need to make assumptions about things and it probably wouldn’t look right)
again, thanks for the info on uoyabause, i found it very interesting. it reminded me of an old graphics paper i once read which i managed to find again, here’s a link for the interested: http://vcg.isti.cnr.it/publications/papers/quadrendering.pdf
i believe that graphics paper describes exactly what the author of uoyabause was doing. in fact, i think the tessellation is not for perspective rendering, it’s used to get a bilinear mapping similar to what the saturn actually produces (but much nicer). the paper describes a different method of bilinear quad rendering that is more efficient than cpu based tessellation, however uoyabause appears to have since implemented its tessellation approach on the gpu to (obviously) huge gains, how comparable their method would be to that, idk.
as i said in my last post it’s possible to use both 4 points in projected and source space to determine a projective map, which is what uoyabause is able to do. and while this will work for quads that actually went through a projective transform (mostly, i think there are some edge cases where it won’t) there’s no way of knowing if that’s the case, hence for certain games it will produce incorrect results. so in theory, for games that work well with it i think the perspective option in uoyabause is capable of producing slightly better visuals, but if your machine is capable of running with tessellation it’s probably not worth the hassle.