[Engine] GLOOME / [WIP] Project 67 & Nocturne in Yellow

[Ultimate Freedoomer]

• A lot of painstaking work, because you'd have to update that code anyway to make it work within ZDoom, but it should be possible. However, it also seems very pointless, what would you gain from doing that?
• That seems nearly impossible. It'd need a lot of special casing and alternate branching in all core gameplay functions, often falling back to crippled/bugged functions while in demo mode.
• It's free software, if the Zand developers want to take stuff from GLOOME, they can do it without being spoonfed.

For point 1: The Heretic/Hexen compatibility code written specifically as part of ZDOOM specifically is proprietary, since the compatibility was added before that code was officially GPL'd. To quote the wiki:

[The Doom Source License] prohibits commercial use. It naturally applies to all parts of the code originating from the Doom source code. Furthermore, the source code for Heretic and Hexen was released under Activision's standard EULA, which is inapplicable to source code. Kenn Hoekstra of Raven Software allowed to use the terms of the Doom source license instead: "Regarding the Heretic/Hexen source code: According to the licensing agreement that shipped with the game, you really can't do ANYTHING with the source code. The restrictions are such that you could never legally make a mod or distribute the code or modify it or ANYTHING without Raven and/or Activision dropping the elbow on you and causing you great bodily harm. This is a mistake. The bottom line about the Heretic/Hexen source code is that you can pretty much do anything with it that people did with the DOOM source code as long as you don't charge for it or use it to make money." All three games had their source code eventually re-released under the terms of the GPLv2, but ZDoom uses the older licensing scheme since the GPL is incompatible with other licenses used by parts of ZDoom; namely FMOD Ex, Build, and MAME. Note that many parts of Heretic and Hexen support were written before their source code was released, and are original independent work instead.

Basically, by using the official GPL source releases for these 2 games, it allows for having an "official" template for compatibility.

[Gez]

Okay, no.

First, a large part of the Heretic and Hexen support code was written by Randi from scratch, before the source code was released in any form. This code is under the three-point BSD license and perfectly fine from a licensing standpoint.

Secondly, the code from the Activision EULA source release is exactly the same as the code from the GPL re-release. So removing the Activision EULA code and replacing it with completely identical GPL code is nothing but a waste of time, what you do is simply change the licensing terms without touching the code. That's what happened in Doom Legacy and Doomsday.

[Ultimate Freedoomer]

Okay, no.

First, a large part of the Heretic and Hexen support code was written by Randi from scratch, before the source code was released in any form. This code is under the three-point BSD license and perfectly fine from a licensing standpoint.

Secondly, the code from the Activision EULA source release is exactly the same as the code from the GPL re-release. So removing the Activision EULA code and replacing it with completely identical GPL code is nothing but a waste of time, what you do is simply change the licensing terms without touching the code. That's what happened in Doom Legacy and Doomsday.

Fair enough.

[Ultimate Freedoomer]

If I can make a suggestion: How about replacing the Software Renderer with the Cycles Software Renderer from the Blender Tool suite, rather than removing the Software Renderer entirely?

[wildweasel]

If I can make a suggestion: How about replacing the Software Renderer with the Cycles Software Renderer from the Blender Tool suite, rather than removing the Software Renderer entirely?

Is this "Cycles" renderer actually compatible with what Doom needs to do in software, though?

[Ultimate Freedoomer]

I'm not sure. Depends on what you're sepecifically saying "needs to be done". I could ask the developers.

[Shadow Hog]

Isn't this kind of like asking them to insert Quake or Unreal's software renderer in lieu of the Doom-based one that got thrown out? Totally different design at play.

[Ultimate Freedoomer]

Isn't this kind of like asking them to insert Quake or Unreal's software renderer in lieu of the Doom-based one that got thrown out? Totally different design at play.

To be fair:

• This is the most advanced open-source CPU-based Graphical renderer I've seen (all the other really good open-source renderers are purely GPU)
• I know a lot of people preferred the software renderer due to personal system limits. The only issue is that I'm not sure if Cycles can do 2D Sprite graphics (AKA "Doom-Style"). It does use Ray-tracing for its graphics, if that's what's needed.

[zrrion the insect]

Adding a post-process shader would allow people to make shaders to index everything to their palette of choice, and the indexed color thing is the only part of the software renderer that people really want to have.

It would also be much easier to add to the engine than an entirely new renderer.

[Shadow Hog]

Isn't this kind of like asking them to insert Quake or Unreal's software renderer in lieu of the Doom-based one that got thrown out? Totally different design at play.

To be fair:

• This is the most advanced open-source CPU-based Graphical renderer I've seen (all the other really good open-source renderers are purely GPU)
• I know a lot of people preferred the software renderer due to personal system limits. The only issue is that I'm not sure if Cycles can do 2D Sprite graphics (AKA "Doom-Style"). It does use Ray-tracing for its graphics, if that's what's needed.

Yes, I'm sure adding a ray-tracer to Doom is exactly what GLOOME needs. A renderer that runs at a blistering ⅓ frames per second!

It would also be much easier to add to the engine than an entirely new renderer.

I'd imagine the opposite is true, since Blender's renderer was made to work with Blender, and presumably has multiple assumptions made that are true about Blender but not Doom.

I just don't see this happening. Doom is not Blender, so this is trying to shove a square peg down a round hole.

[Ultimate Freedoomer]

Then why not just make a GPL software renderer from scratch that does what's needed? Just replace the proprietary code in that part with from-scratch GPL code that allows for the same functionality as what was covered by the proprietary code.

[wildweasel]

Then why not just make a GPL software renderer from scratch that does what's needed? Just replace the proprietary code in that part with from-scratch GPL code that allows for the same functionality as what was covered by the proprietary code.

That's nowhere near as easy as it sounds. Doom's renderer does a lot of things that would be considered extremely unusual by modern standards. I suppose if Doom compatibility were to be thrown out the window, you might not necessarily need to support all the "map hacks" out there, but you would still need to support things like 3D floors, translucency, slopes, particles, sector coloring, and the like.

[Ultimate Freedoomer]

Then why not just make a GPL software renderer from scratch that does what's needed? Just replace the proprietary code in that part with from-scratch GPL code that allows for the same functionality as what was covered by the proprietary code.

That's nowhere near as easy as it sounds. Doom's renderer does a lot of things that would be considered extremely unusual by modern standards. I suppose if Doom compatibility were to be thrown out the window, you might not necessarily need to support all the "map hacks" out there, but you would still need to support things like 3D floors, translucency, slopes, particles, sector coloring, and the like.

I know how difficult it is. However, it'd be so Celestia-damn worth it. Besides, I thought all those effects were hardware renderer-only features.

[YukiHerz]

Adding a "software renderer" that can't do stuff that the GL one can would be kinda pointless for something like gloome, also, many things list are available to Zdoom's renderer.

[Marrub]

Then why not just make a GPL software renderer from scratch that does what's needed? Just replace the proprietary code in that part with from-scratch GPL code that allows for the same functionality as what was covered by the proprietary code.

That's nowhere near as easy as it sounds. Doom's renderer does a lot of things that would be considered extremely unusual by modern standards. I suppose if Doom compatibility were to be thrown out the window, you might not necessarily need to support all the "map hacks" out there, but you would still need to support things like 3D floors, translucency, slopes, particles, sector coloring, and the like.

I know how difficult it is. However, it'd be so Celestia-damn worth it. Besides, I thought all those effects were hardware renderer-only features.

Sure, thanks for the offer, I'll merge it when you get it finished.

---