Renderer: unused features, untested features, and unported features

[illwieckz]

One a side note of this:

• shaders: Remove some ET only shaders. #661

Remove sunShader and flareShader. They are only used in ET and not
actually used anywhere in the engine. They just spam us.

I would like to know what those features were for and if we can benefit from them.

We have many things that are not working and because we don't use them no one fixes them or port them, and with time they just get deleted.

• we have water code, but it currently does not work, we can see there we had one day a working implementation (maybe in a branch, though): https://unvanquished.net/the-human-model-and-new-map-features.
• we have cubemapping with automatic cubemap generation, it's mostly working now, however some issues still remain, see Static reflections issues #1310.
• we have HDR lightmap code, untested, even some code was even removed when doing clean-up: Remove unused libs/openexr #467 . For information the related q3map2 code exists in our old daemonmap (wolfmap), there also exist another q3map2 patch by some OpenJK developers.
• we have something that may be direct sunlight or direct sun shadow I don't know but no one knows if it had ever worked once, and it has to be ported over the tiled renderer.
• we have dynamic shadows but they were badly broken and they have to be ported over to the tiled renderer.
• the PBR code is untested and is likely wrong (I suspect the roughness to be inverted, if yes it's easy to fix, I suspect the metalness to be wrong, I don't know the fix).

I would like to nuke the old forward renderer one day, but then we would nuke code we want to port.

The only successful feature restoration and fix (XreaL was wrong) I know was the parallax mapping stuff:

• WIP: fix heightmap orientation, black is low and white is high #170
• refactor and fix normalmap, parallax, reflectionmap, glowmap, GL/DX normal switch #180

Screenshot with working water texture from 2012 (Citadel map):

[ghost]

we have water code,

would be nice to have. None of unv's official maps really use water, but several trem maps do.

we have direct sunlight but no one knows if it had ever worked once, and it has to be ported over the tiled renderer.

Most maps from trem and unv that unv are don't really feature exteriors, or they're a detail. I think this could be dropped.

we have dynamic shadows

Current stuff is to use blobs. It's quite ugly, though, so I'd say real shadows would be nice, but we can live without it, I guess.

Of course, this is the PoV of a player only, as I don't hack the engine.

[illwieckz]

On the other hand people may start to use features once they work.

And we know that: Unvanquished maps do not rely on darkness because we don't have a proper way to render nice dark lightmaps (either HDR, either sRGB). That's the perfect example of “things that looks bad are avoided”.

[illwieckz]

Here is an example of how looks ATCS (not HD) map on Q3 tremulous mod on ioquake3 with classic lighting:

Here is an example of how looks ATCS (not HD) map on Q3 tremulous mod on ioquake3 with r_forceSun 1:

Also not that it does not benefit from specular/normal/relief mapping here as none of this is implemented.

[DolceTriade]

Wow this would be really cool to have in Unv, what features are being used there?

[illwieckz]

• in Citadel screenshot: only some supposedly old Dæmon's water GLSL shader, the material was probably edited to produce the screenshot (I don't know who did it),
• in ATCS screenshot: only the ioquake3 sun GLSL shader (the data is unmodified).

Both maps are legacy maps done the Quake 3 way without any other fanciness we may support.

[illwieckz]

Current stuff is to use blobs.

@bmorel other options are not listed in menu on purpose because they are broken AND they are supposedly not compatible with our new renderer anyway. Because the old renderer isn't used it isn't tested and it may be broken because it rots while we edit other things in newer renderer.

You can see some examples of nice shadows on those screenshots from 2014/2015 (alpha 34, 41, 42):

[DolceTriade]

Shadows was always on our wishlist and we never got them working because we never had a performant dynamic light implementation. We no longer have anyone with real graphics expertise (maybe slipher? :D)

[illwieckz]

We may want to summon @gimhael, @Amanieu and @cmf028! 😁️

@Kangz has good graphics expertise too, but I would prefer to see him focusing on the port from NaCl to Wasm. 😉️

I remember @cmf028 even had a work-in-progress raytracing code (2019). 😲️

There was also some experiment about lightmap filtering (2019):

About shadows, see also https://imgur.com/hVxHh,ZnLTa,YIRTN (2012):

[DolceTriade]

If we can summon some of our older devs, that would be amazing :D

[slipher]

Apparently at some point, a subset of non-blob shadows were made to work while tiled mode was enabled, by just using the forward lighting code for them. Specifically, "inverse dynamic lights" which are added by the cgame for players and buildables. a09f03b