Raytracing in GZDoom possible?

[mankubus]

Would it be possible to have raytracing on GZDoom?

 

I find this technology amazing and I believe in a few years it will make sense to play wads with it. It works specially good with the eerie PSXDoom vibe.

The potential is definitely there if fine tuned. Some neat moments here like the 2 candles on the floor in the pitch dark room with the shadows of the hellknights creeping in.

 

Im pretty sure that's how Carmack and co imagined Doom back in 93.

Now it begs the question: Can GZDoom have this? I would love to see the result in the proper PSXDoom total conversion with the reverbs etc, prboom can't do none of that.

[Edward850]

Technically anything is possible if you chuck enough code at the problem. It's finding someone who wants to do the work is the issue.

 

So that begs the question; do you want to do it yourself, or are you prepared to pay someone else to do the work for you? Because otherwise you just have to wait for someone else who has interest in it themselves.

[Dark Pulse]

Also, keep in mind not everyone has a GPU that can do it. Do you want to put in all that work for something only a subset of users can use?

 

Also:

3 hours ago, mankubus said:

Im pretty sure that's how Carmack and co imagined Doom back in 93.

No. No they did not.

 

They knew full well the limits of the hardware. Even expensive SGI workstations (much less the NeXT systems they were using) couldn't even do realtime raytracing at that point, I'm pretty sure.

 

I remember Quake 3 Ray-Traced boasting that it was getting 20 FPS at 512x512 resolution with 4xFSAA... and a network of computers that reached 36 GHz.

 

This was in 2004.

 

The fact that it took nearly another twenty years before raytracing could even begin to be thought of as even semi-common should show just how hard it is to actually do it.

 

1993? Forget it, buddy. That's Jetsons-level stuff. You didn't even have fast floating-point numbers yet!

Edited May 14, 2022 by Dark Pulse

[Gez]

3 hours ago, mankubus said:

Can GZDoom have this?

Yes, if you find a developer that has:

• The technical knowledge for that
• The motivation for that
• The hardware for that

This is like everything else in open source software development. People work on what they can work on and want to work on.

[Gibbon]

4 hours ago, Edward850 said:

Technically anything is possible if you chuck enough code at the problem. It's finding someone who wants to do the work is the issue.

 

So that begs the question; do you want to do it yourself, or are you prepared to pay someone else to do the work for you? Because otherwise you just have to wait for someone else who has interest in it themselves.

Exactly this.  It’s great being an ‘ideas person’.  But unless someone wants to do this and has the hardware capable of it, then you have to wait.

 

Raytracing for everyone won’t be possible unless even integrated graphics have it.  For the foreseeable future, it is restricted to gaming pc’s.

[Redneckerz]

26 minutes ago, Gibbon said:

Raytracing for everyone won’t be possible unless even integrated graphics have it.  For the foreseeable future, it is restricted to gaming pc’s.

Ackually... the Ryzen 6000 series feature RDNA2-based Radeon 660M and 680M iGPU's... and they do have ray tracing accelerators. The 680M barely has a use for it unless you keep it to 720p and lower, but it is there.

[LuciferSam86]

I think Red and Gibbon are right. 

But for see an integrated GPU being able to do ray tracing at 60+ fps maybe we should wait the next generation? ( I mean next next :) ) 

[TheMagicMushroomMan]

I'm more interested in those player shadows than anything. PSX DOOM looks a bit better with RTX than standard DOOM, but I still think it looks really gaudy and goofy apart from the aforementioned player shadows.

[Shepardus]

You could try the Relighting mod, which technically isn't raytracing but falls in a similar vein of "reinterpret Doom's lighting and make it more dynamic," for better or for worse.

[Edward850]

1 hour ago, Shepardus said:

You could try the Relighting mod, which technically isn't raytracing

That's not really the right use of the word. It's like saying that an orange technically isn't an airplane. The sentence itself is truthful but it's withholding the complete picture.

Edited May 15, 2022 by Edward850

[Metal_Slayer]

On 5/14/2022 at 12:41 AM, mankubus said:

I believe in a few years it will make sense to play wads with it.

If every wad creator tweak their maps to support it in a way that doesn't change their vision or if someone makes a map specifically made for it, sure.

 

On 5/14/2022 at 12:41 AM, mankubus said:

Im pretty sure that's how Carmack and co imagined Doom back in 93.

That's definitively not how they imagined it, John Carmack saw the custom engine for the Sega Saturn port and said it didn't looked like Doom, that got all scraped and they had to try to adapt the PSX port for it, and considering the way other FPS games looked on the system that port probably was way more advanced than any other port at the time. Doom is simplistic, abstract and unrealistic by design choice.

 

On 5/14/2022 at 12:41 AM, mankubus said:

Now it begs the question: Can GZDoom have this? I would love to see the result in the proper PSXDoom total conversion with the reverbs etc, prboom can't do none of that.

It could happen, but it would probably have single digit frame-rates. Also, PrBoom couldn't do Path Tracing, but now it can, it's just that source ports that want to remain Vanilla compatible evolve at a slower pace than source ports that change the game's physics in order to add more features.

Edited May 15, 2022 by Metal_Slayer

[mankubus]

On 5/14/2022 at 8:31 AM, Dark Pulse said:

No. No they did not.

I mean in their minds, they imagined the shadows and stuff happening and would have done it like that if possible. At least im sure Carmack did.

 

On 5/14/2022 at 8:31 AM, Dark Pulse said:

Also, keep in mind not everyone has a GPU that can do it. Do you want to put in all that work for something only a subset of users can use?
 

 

In the future eventually the gpus that can run this smoothly will be affordable.

Edited May 16, 2022 by mankubus

[Dark Pulse]

24 minutes ago, mankubus said:

I mean in their minds, they imagined the shadows and stuff happening and would have done it like that if possible. At least im sure Carmack did.

No, uh... no they really didn't. Nothing had shadows in Doom, because processing those would've taken way more power.

 

Key to remember is that Doom did not run at 35 FPS on hardware of the day! Your bread-and-butter 386 DX-33 ran DEMO3's Timedemo at like 18 FPS. It took really high-end 486 chips (80+ MHz) or Pentiums before Doom would run at a generally locked 35 FPS.

 

I mean, they sold Doom 3's shadows like hell because that was the first time something resembling realistic lighting was possible. Until then, it was either no shadows or pretty simple blob shadows, and Doom's lighting model was very simplistic because speed was what mattered more than looks.

 

The Shadowcaster engine that Carmack did inbetween Wolf and Doom (and considered kind of halfway between them as a result) was actually fancier in a few ways (it had slopes, for example), but it also ran much slower than Wolf's engine, but that was in turn more suitable for a slower RPG-type game as opposed to the fast run-and-gun of Wolf/Doom.

 

Maybe in Adrian Carmack or Tom Hall's minds, there might've been stuff like that, but it would've been a case of fitting to what the engine could do rather than to try to make it work. Carmack and Romero knew what the heck could and couldn't be done.

 

24 minutes ago, mankubus said:

In the future eventually the gpus that can run this smoothly will be affordable.

Naturally. That ain't now though. It's starting to trickle down - the latest consoles have that tech, and even the Steam Deck has it at a roughly $400 price point.

 

But the days where your most basic GPUs/on-die IGPs/APUs have them is still a few years off. And even then, it needs to be able to do it at acceptable performance.

 

And it'd still need someone interested enough in doing the work in the first place to make it happen.

Edited May 16, 2022 by Dark Pulse

[Metal_Slayer]

28 minutes ago, mankubus said:

I mean in their minds, they imagined the shadows and stuff happening and would have done it like that if possible. At least im sure Carmack did.

Doom was going to have more shadows in the sectors, but the map designers thought that it was too much effort for something that was barely noticeable. Also, before Doom 3 was conceptualized John Carmack wanted to remake Doom with Id Tech 4, but the original artists didn't liked that idea, they wanted the classics to stay where they were, this is why we got Doom 3 instead.

 

37 minutes ago, mankubus said:

In the future eventually the gpus that can run this smoothly will be affordable.

Sure, if it was in the near future that would be a good point, but I think that kind of GPU getting cheap is only going to happen in at least 10 or 15 years away from now. Just look at this video to see how unoptimized GZDoom is.

Other than that, the fact you are using Carmack as the only example doesn't make sense, the thing he wanted the most was to make games showcasing technology, if it wasn't for the other members of Id Software these games would have been just like Quake 2/4 or Rage.

[Dark Pulse]

2 hours ago, Metal_Slayer said:

Just look at this video to see how unoptimized GZDoom is.

This isn't exactly a fair comparison to make, because GZDoom is a far more complex engine capable of far more intensive things than regular Doom demands.

 

Also, considering that video came out in 2021, a CPU from 2015 and a GPU from 2016 aren't exactly unreasonable to ask for - and that's the "recommended" options. Minimum is even lower (2012 on the CPU, 2013 on the GPU).

 

And frankly, even though I don't know what hardware that guy has in his video, it never dips below 35. Which... was the original Doom's maximum rendering rate. Contemporary hardware when Doom came out didn't even really manage 20 FPS at a near-max screen size.

 

People are fucking spoiled. And they forget Doom is not like a traditional 3D engine, which is what these fancy-ass cards are designed for.

 

Anyway, I just checked it myself. Ryzen 9 5900X. GeForce 1080 (so yes, older than that 2080 mentioned in the video). 2560x1440 resolution. I was getting like 130 FPS in the town map. About the same in Windmill Acres; worst I got was like 110 FPS.

 

What sucked are those people's CPUs, not the engine.

[Metal_Slayer]

17 minutes ago, Dark Pulse said:

This isn't exactly a fair comparison to make, because GZDoom is a far more complex engine capable of far more intensive things than regular Doom demands.

The map in question has 3d floors and scripting, and that's it, which is complex but still should have a decent framerate, but GZDoom has to do a lot of stuff just for a single action to happen, and that's the problem.

 

23 minutes ago, Dark Pulse said:

Anyway, I just checked it myself. Ryzen 9 5900X. GeForce 1080 (so yes, older than that 2080 mentioned in the video). 2560x1440 resolution. I was getting like 130 FPS in the town map. About the same in Windmill Acres; worst I got was like 110 FPS.

 

What sucked are those people's CPUs, not the engine.

GZDoom also has the problem of sometimes even when you have a better hardware it runs worse than it should.

 

Anyway, all of these complex capabilities are nothing compared to the Path Tracing. The reason PRBoom+ was chosen for that probably was because it was the only one that could do that on a decent frame-rate.

[Gez]

3 hours ago, Metal_Slayer said:

Sure, if it was in the near future that would be a good point, but I think that kind of GPU getting cheap is only going to happen in at least 10 or 15 years away from now. Just look at this video to see how unoptimized GZDoom is.

That video is fucking stupid and I dare the complainers to make a port that runs faster on the same kind of maps if they think they're so much better than Graf.

 

23 minutes ago, Metal_Slayer said:

The map in question has 3d floors and scripting, and that's it

It's also a wide open map where the entire level is always visible at once.

 

Fun fact: the entire design of the Doom engine is based on the binary space partition tree, which is a tool designed to quickly cull away any sector that is hidden from view. That's what allowed to get somewhat decent performances (at the time, 15+ FPS were considered decent; when nowadays people scream bloody murder if they get less than 240 FPS) on the hardware of the era, just how much stuff they could get to avoid rendering.

 

Now try to guess how useful the BSP can be when it cannot actually cull anything.

[Bauul]

4 hours ago, Metal_Slayer said:

Just look at this video to see how unoptimized GZDoom is.

 

Few things are as head-scratching as someone uneducated on a subject trying to make fun of something they don't understand. 

 

Good lord this is a terrible video, but more so, you even pretending that it constitutes actual evidence of GZDoom being unoptimized is something you shouldn't feel very proud of.

[Graf Zahl]

It is a well known fact that the Doom engine is not good at handling wide open maps. The Build engine isn't either. It's a testament to modern CPU performance that we can get away with maps like Frozen Time, BoA or Elementalism these days. To get more juice out of these we'd need some radical changes to how the map needs to be processed - and these cannot be easily grafted onto existing maps and require educating the mappers to be aware of the needed restrictions.

 

The classic BSP approach is right at its limit - current CPU and CPU cache performance won't allow more. We may get 20% more if we could finally ditch OpenGL and fully multithread the renderer, but with a current rate of 15-20% of graphics hardware not capable of using modern APIs and still lots of old dual core CPUs around that's out of the question for the time being.

Edited May 16, 2022 by Graf Zahl

[ReaperAA]

Most comments in that video are more cringe than that video itself.

[Bridgeburner56]

GZDoom can handle the shit I put it through. I'd say it's pretty damn well optimised.

[Gibbon]

2 hours ago, Bauul said:

 

Few things are as head-scratching as someone uneducated on a subject trying to make fun of something they don't understand. 

 

Good lord this is a terrible video, but more so, you even pretending that it constitutes actual evidence of GZDoom being unoptimized is something you shouldn't feel very proud of.

 

Folks that constantly say "oh it needs optimising" probably have no clue what optimisation actually means, they just hear it and think it makes them sound smart but instead it just highlights how uneducated and moronic they are.  They wouldn't be able to optimise themselves out of a cardboard box let alone discuss such things in any intelligent manner.

Edited May 16, 2022 by Gibbon

[Edward850]

I've once had someone claim a game "lacked optimisation" over their legacy GPU failing to initialize D3D11, so I'm frankly of the position that if you want to talk optimisation you better first bring code and/or statistics to the table. It's a rather pointless topic if there's no base line.

 

You can't just slap a wad into a doom port and yell unoptimized, there's simply no information that it shows by itself and no analysis has been done.

Edited May 16, 2022 by Edward850

[Gibbon]

22 minutes ago, Edward850 said:

I've once had someone claim a game "lacked optimisation" over their legacy GPU failing to initialize D3D11, so I'm frankly of the position that if you want to talk optimisation you better first bring code and/or statistics to the table. It's a rather pointless topic if there's no base line.

 

You can't just slap a wad into a doom port and yell unoptimized, there's simply no information that it shows by itself and no analysis has been done.

The best part is when they will send you some URL where someone else has said it and they are just repeating it.  That's already 90% of the users..  shame really.  In this age where everything is visible and people can educate themselves.

Edited May 16, 2022 by Gibbon

[Hyacsho]

Interesting

Edited May 16, 2022 by Hyacsho

[Metal_Slayer]

I think I accidentally changed this topic from whether or not GZDoom could do Ray Tracing to whether or not GZDoom is optimized. Of course that video is exaggerated, it has comedic intent, it was just that the video was recommended to me on a perfect timing an I thought I had to link it here even if it didn't prove anything. Besides, I have nothing against this source port, I even use it when it's necessary, I told the same joke to a GZDoom dev on Twitter when he was talking about RT and he said that I was probably right.

9 hours ago, Graf Zahl said:

To get more juice out of these we'd need some radical changes to how the map needs to be processed - and these cannot be easily grafted onto existing maps and require educating the mappers to be aware of the needed restrictions.

 

The classic BSP approach is right at its limit - current CPU and CPU cache performance won't allow more. We may get 20% more if we could finally ditch OpenGL and fully multithread the renderer, but with a current rate of 15-20% of graphics hardware not capable of using modern APIs and still lots of old dual core CPUs around that's out of the question for the time being.

That's fair, I know that if you changed the way things work on GZDoom probably a lot of things would break, besides, if there was a simple way to make it run better it would have been implemented already.

[Gibbon]

5 minutes ago, Metal_Slayer said:

I think I accidentally changed this topic from whether or not GZDoom could do Ray Tracing to whether or not GZDoom is optimized. Of course that video is exaggerated, it has comedic intent, it was just that the video was recommended to me on a perfect timing an I thought I had to link it here even if it didn't prove anything. Besides, I have nothing against this source port, I even use it when it's necessary, I told the same joke to a GZDoom dev on Twitter when he was talking about RT and he said that I was probably right.

That's fair, I know that if you changed the way things work on GZDoom probably a lot of things would break, besides, if there was a simple way to make it run better it would have been implemented already.

It already runs pretty nicely.  On an M1 Mac it literally flies..  shame they don’t do 140hz screens..

[mankubus]

16 hours ago, Dark Pulse said:

 

 

I mean, they sold Doom 3's shadows like hell because that was the first time something resembling realistic lighting was possible. Until then, it was either no shadows or pretty simple blob shadows, and Doom's lighting model was very simplistic because speed was what mattered more than looks.

I know, what I mean is, Carmack wished to have the technology to add in shadows and stuff back then so if I was Carmack, I would already be imagining how games would look like in 10 years and wishing I had a time machine to add this technology, I know Doom 3 was the first to add in real time shadows (well in fact Blade: The Edge of Darkness by some spanish developers had some cool shadows going on already). In fact I think Carmack is quoted somewhere saying how Doom 3 was how he wanted Doom 1 to look like, luckily the limitations in technology may made them take a more fast paced route since without the high end graphics it would just be boring to have realistic running physics etc.

 

Also Carmack wanted to remove bunnyhoping in Quake, but also thank god they keep it because the game would be boring without it specially pvp.

Edited May 16, 2022 by mankubus

[Dark Pulse]

2 hours ago, mankubus said:

I know, what I mean is, Carmack wished to have the technology to add in shadows and stuff back then so if I was Carmack, I would already be imagining how games would look like in 10 years and wishing I had a time machine to add this technology, I know Doom 3 was the first to add in real time shadows (well in fact Blade: The Edge of Darkness by some spanish developers had some cool shadows going on already). In fact I think Carmack is quoted somewhere saying how Doom 3 was how he wanted Doom 1 to look like, luckily the limitations in technology may made them take a more fast paced route since without the high end graphics it would just be boring to have realistic running physics etc.

 

Also Carmack wanted to remove bunnyhoping in Quake, but also thank god they keep it because the game would be boring without it specially pvp.

The fact that Carmack spent his time focusing on maximizing what he could get out of a system instead of wishing for things that it just would never do is what makes him Carmack.

 

I mean, yes, he'd certainly have put some thought into it, but ironically, even if Doom 3 was his desired look, the gameplay was definitely anything but, which led to the middling reception Doom 3 got from some of the fanbase (myself included).

 

Bunnyhopping was a bug that he removed but put back in by popular demand, yes. And unfortunately it's also what ruined the game for me, as maps were simply not designed for it in mind. So I've only played a little bit of Quake, but a hell of a lot of UT99.

[mankubus]

3 hours ago, Dark Pulse said:

The fact that Carmack spent his time focusing on maximizing what he could get out of a system instead of wishing for things that it just would never do is what makes him Carmack.

 

I mean, yes, he'd certainly have put some thought into it, but ironically, even if Doom 3 was his desired look, the gameplay was definitely anything but, which led to the middling reception Doom 3 got from some of the fanbase (myself included).

 

Bunnyhopping was a bug that he removed but put back in by popular demand, yes. And unfortunately it's also what ruined the game for me, as maps were simply not designed for it in mind. So I've only played a little bit of Quake, but a hell of a lot of UT99.

There's many tricks in the dm maps that make the game a lot more interesting than if it was just running and shooting.

 

https://www.youtube.com/watch?v=MZBK-gf7lr4&list=PLvMshQnM8rSuzxlmZSL6cfYanQ3OnVMK3&index=1

 

Of course ut99 was more fun for casual play. Quake was brutal if you meet an skilled player but more rewarding if you managed to improve enough.

Edited May 16, 2022 by mankubus