[REL/FINAL] GZDoom-GPL 2.4 - now with software renderer

[Shadow Hog]

Personally, I'd be interested in seeing some sort of colormap-based lighting solution for the hardware renderer that mimics the software renderer's lighting, even more than the existing "Software" lighting mode already does, right down to the banding. Maybe do some linear interpolation between the different levels in the COLORMAP lump for intermediary steps (though this would presumably still look kinda garish).

[darkhog]

Half of this image is the software renderer, the other half is OpenGL. Can you tell, from a quick glance, which is which?

If you don't want dynamic lights, don't add them into your project. Lights and filters has always been optional. Stock GZDoom has no lights and the filtering can be turned off in the options menu.

That's easy, right one. No pixelation/palette banding in the left one.

[darkhog]

I honestly can't see why anyone who isn't running vanilla would take an alpha-less render with Z-axis scaling problems and color limits over OpenGL.

For the authentic colormap, coloring over distance, and unique shading and lighting?

There's plenty of reasons to prefer Software over Hardware. That OGL is the only thing supported is more than understandable (THANKS KEN SILVERMAN), but it'd still be fantastic if a coding wizard with too much time on his hands was able to whip up something. Nigh impossible, mind, but still.
Ultimately the player should be able to pick and choose how they want to experience it, not have us force it on them.

Well, Doom engine is GPL'd and last time I've checked it contains a software renderer. Would need to port it all over again and then implement missing parts (3d floors/slopes/decals) manually, without Ken's code, but it is doable.

//edit: Quake1 also had a software renderer AFAIK so part of rendering code from it could be lifted as well. Obviously it wouldn't be straight copy-paste due to differences of the two engines, but it'd be doable with some elbow grease.

[Nash]

Good luck, and have fun! It took ZDoom 17 years to have 3D floors, slopes, decals and DECORATE, I'm sure if you tried hard enough, you could do it in half the time!

[wildweasel]

//edit: Quake1 also had a software renderer AFAIK so part of rendering code from it could be lifted as well. Obviously it wouldn't be straight copy-paste due to differences of the two engines, but it'd be doable with some elbow grease.

Vavoom tried that some years ago. If I remember correctly, it didn't end well.

[JPL]

If the limited palette is the main difference people can identify in that side-by-side comparison, has anyone tried writing a shader to quantize a full color frame to the Doom palette? Is this easy to hack in with the current GZDoom shader situation?

[Nash]

JPL: I suggested this to Graf some years ago and he said he wasn't interested and the whole reason to have a full coloured renderer is to not have banding...

[raymoohawk]

jpl its not just the limited pallete, its also the horrendous sprite clipping. a while ago gooberman was working on a vanilla faithful opengl rederer, but i dont know if he's still working on it

https://www.doomworld.com/vb/source-por ... g-library/

[darkhog]

jpl its not just the limited pallete, its also the horrendous sprite clipping. a while ago gooberman was working on a vanilla faithful opengl rederer, but i dont know if he's still working on it

https://www.doomworld.com/vb/source-por ... g-library/

Looks interesting. Kinda feel bad that Nash is unwilling to decouple from GZDoom mainline and pick up this rendering engine (even if it's in stasis, code can still be picked up and worked on again).

[Caligari87]

How about you go bug the GLOOME devs then? They're perfectly happy to decouple from the GZDoom codebase and I hear they love to add every little thing people ask them.

[Nash]

I don't call the shots, I will follow whatever Graf Zahl wants for his engine. I'm not the programmer here. Also, last I checked, Gooberman is U L T R A B U S Y (he works at Remedy making triple A games, for example Quantum Break) and realistically we probably won't even see anything usable/runnable from that library of his for a very, very long time!

[darkhog]

That's why I've sent him a PM on Doomworld asking if he'd be able to part with the sources if he can't develop it for one reason or another. Anyway, yeah.

Also I've thought GLOOME was abandoned GPL fork and only GZDOOM-GPL is left. Guess I was wrong.

[Nash]

On a slightly offtopic note; the new DOOM has classic levels as hidden secrets, and when you enter these areas, you actually get to see what banded shading would look like in a full-colored renderer. I thought that was pretty cool and can imagine how GZDoom would look like with a banded shader.

[The Zombie Killer]

//edit: Quake1 also had a software renderer AFAIK so part of rendering code from it could be lifted as well. Obviously it wouldn't be straight copy-paste due to differences of the two engines, but it'd be doable with some elbow grease.

"some elbow grease" is a bit of an understatement here

[leileilol]

If the limited palette is the main difference people can identify in that side-by-side comparison, has anyone tried writing a shader to quantize a full color frame to the Doom palette? Is this easy to hack in with the current GZDoom shader situation?

Probably needs a post-process deferred-esque pipeline to do it right:

---

1. render another scene pass with all textures/sprites as normal, with the lighting set at fullbright (call this buffer 1)
2. render a scene pass with white textures/sprites and lighting to a buffer, including adding "glow" textures/sprites with no saturation (call this buffer 2)
3. Reduce buffer1 to 6-bits of color (for 64 shades per channel, as per VGA (and the sake of your shader compiler))
4. Reduce buffer2 to 5-bits of intensity (for 32 shades)
5. Have buffer1 go through a lookup operation to assign an integer color index for a pixel by nearest color in the palette
6. Apply index to colormap
7. Get it back to RGB by reverse lookup with the index to the palette and out it


Or you could just go whole hog and palettize the entire screen buffer, but that's also slow


It's not good for OA to throwback to Quake as there is a lightmap bilinear filter effect making too slanted lighting transitions giving more than 1 shade to a texel, though in gzdoom this would be a non-issue with the old lighting model