Unity fucked up hard here and I hope that their planetary-level screw up will lead to game developers pushing for open source engines to avoid the control of their games being stolen.

I'm not saying there aren't talented developers working in open source. But the sheer breadth of expertise required is unimaginable. You need top-of-their-field engineers from practically every conceivable discipline within CS to build a AAA game engine. Physics, lighting, rendering, networking, audio, UI, and that's just the tip of what I can think of. Engines like Rockstar's RAGE are easily on par with the Linux kernel for complexity.

But you've mentioned it yourself, so you presumably don't see that as a contradiction.

What do you think makes the complexity of Linux achievable with FOSS while the comparable complexity of a AAA engine not?

It just comes down to incentives. Practically every living human being stood to gain from the existence of a high quality general purpose FOSS operating system, and so Linux naturally came about.

The people who would benefit from a AAA open source game engine are... closed source AAA game development studios. As such there's really no incentive for some physics whiz to spend their extremely valuable time toiling away on something that is only going to be used for someone else's profit. The intersection of people who build game engines, and people who make games with those engines, is extremely small.

There's really no such thing as open-source game development except for hobbyists, because that would be literally giving your product away. Games are a hit based, one-and-done type product much more akin to movies than other software.

Clearly there's something because it hasn't been done. Why do you think there are no high-quality FOSS engines?

There are many more or less serious potential explanations: not enough people care, it wasn't (or still isn't) financially feasible, the people able to develop AAA engines are actively against sharing source or ideas, there's an engine development cartel actively pushing against it to keep their revenue.

Or it might just be a social or historical accident -- we may just have been extremely lucky with Linux and projects on that scale will never come again.

Or maybe everyone thought it would be a great idea but they also thought it would never work and so no one seriously ever started an open source engine. Maybe Godot will be a true AAA engine that will surpass them all in a few years.

I don't know.

In my opinion, the problem rather is that the skills that are helpful/necessary to build "typical" open source software are really different from the skills for a good game engine.

About this time last year, I wanted to make a simple little 2D platform game in Godot and my experience was mixed. Some stuff was really easy and pleasant, some stuff was middling and then other stuff was frustrating enough that I gave up: for example, I had to spend an entire day just so I could get sprites correctly sorted so that tilemap tiles and objects that were in front of the player would be drawn in front and those that were behind were drawn behind. Basic stuff. There’s an option to enable for this (y-sort) but it did not work without a bunch of unintuitive tweaking. The docuentation didn’t help, reddit couldn’t help, their discord couldn’t help and I wasted a lot of time on it.

Having said that, I have high hopes for Godot and I do think it has a bright future, but it has a ways to go. I’ve even made some (very small) contributions to the gdnative c++ library, so its not like I’m just complaining ;)

My point is that Godot doesn’t get much interest for more reasons than just consoles (there’s commercial support for porting available). But, as you say, the culture change is happening, it just needs time.

https://docs.godotengine.org/en/3.0/tutorials/platform/conso...

Did it? Lot's of gamers see consoles as something that holds developers back from using better hardware, since they need to target 5 year old systems. Quality both artistic and technical isn't something consoles can claim to be leading in. And clearly, "consolization" in its various forms isn't something gamers appreciate, when it spills out into PC gaming.

And that in spite of some bad apples still going through the gates, the large majority of flappy bird clones never makes.

Incumbent consoles are trying to dig themselves out of this perception now, but they got it very deservedly.

The average game on a console is going to be higher quality than the average game on PC because the average game on PC has to include the game I made in Visual Basic 6 when I was in high school. With no gatekeeper ensuring basic quality, my VB6 game is every bit as legitimate of a game as Battlefield 5. They both hold the title of "PC Game", but only one of them could ever be called "Xbox Game" because Microsoft would never allow my game on their console.

Technical limitations that hold developers back are only part of it. Another issue is simply creative control of incumbent console owners. PC gaming doesn't have it, so creators can do whatever they want. And masterpieces are always a minority, no matter in what form of art.

Pre-crash there were tons of high quality artistic masterpieces on consoles too. But it was swimming in absolute garbage [1], turning a lot of customers off [2], losing their trust [3], and threatening the entire platform [4]. If you haven't followed any of these links yet, PC gaming still has that problem.

The argument isn't that PCs have more powerful hardware (the reality of which is debatable [5]). The argument is "do console makers guarantee quality better post-crash than they did pre-crash" and the answer is unequivocally yes. The question you then raised was "do console makers guarantee quality better than PC games" and I would still argue unequivocally yes. And then I would point out that PC gaming benefits from this, because if Activision wants Call of Duty to sell on consoles, they're going to make sure it passes Sony and Microsoft's quality standards, which then the PC game most likely will pass as well.

This isn't always true, of course, because there are plenty of times a game runs better on consoles than it does on PC [6]. That's probably what you refer to as "consolization", but again that's just missing the point. People buy consoles these days because they work and they work consistently. That's directly the result of the post-crash quality control that console makers implemented.

[1] https://kotaku.com/unfinished-steam-game-abandoned-after-tho...

[2] https://www.theverge.com/2017/4/4/15172908/valve-steam-explo...

[3] https://www.greenmangaming.com/newsroom/2017/09/27/valve-rem...

[4] https://kotaku.com/the-people-fighting-to-keep-crappy-games-...

[5] https://store.steampowered.com/hwsurvey/Steam-Hardware-Softw...

[6] http://www.escapistmagazine.com/forums/read/9.937131-Let-me-...

> That's probably what you refer to as "consolization"

No, I refer to cut down design, oversimplified interfaces, lack of depth and etc. which were characteristic for console games, backfiring to PC games, when developers don't want to do extra work and simply use "one size fits all" method to save time.

Technical limitations is only part of the problem. The bigger one I'd say is the incumbents' control over the platform and heavy mass market bend. Quality has many meanings, and poor art (in many meanings of the word art, not simply graphics like you might think) caused by mass market commercialization can justifiably be understood as reduced quality.

So, I'll stick to what I said. Incumbent consoles didn't save games from worse quality, they actually made them worse.

For example in demoscene the art is to make these old consoles or computers do wonderful things that seem impossible on such limited resources.

> There's probably less than a few thousand people on earth with the level of skill and expertise to build something at the scale of UE4.

That's really bunk. I mean "only elite can do it" it claim. Sure, it's not something you can create in one day, but it's not something that out of reach either, especially when people are collaborating on it.

The graveyard of hundreds of abandoned open source game engines begs to disagree with you. I agree that it seems absurd, but you really can't underestimate the amount of man hours put into these things. Unreal has been under constant development for over 20 years.

It's the same as flight simulation. Why is there only one viable flight simulator (X-Plane) on the market? It's because that kind of coding is simply beyond 99% of developers, and it takes a huge well funded and focused team to make something state of the art.

I wouldn't cite open source codecs as a success story ...

A GUI toolkit is probably more on point and of the correct scale, and those also demonstrate that without significant backing from somewhere, progress doesn't get made at that level of complexity.

A commercial quality game engine is a huge project, and as such, requires a huge projects worth of time and effort to build. Same as any other huge software project (which all have countless abandoned open source attempts). Remember that most open source projects start of tiny (one developer is common, certainly very few start off with more than a handful) and work on it in their free time, while commercial teams like Unity have hundreds of peolpe working on it full time.

The reason they are abandoned is typicaally that 1) the developers, who are doing it in their spare time, don’t have the time anymore; or 2) they get frustrated at the amount of work/lack of contributors/lack of interest and stop working on it; or 3) they simply lose interest and work on something else.

Its not lack of ability, its lack of time/motivation/interest to keep working on it for many, many years.

- Understanding of modern CPUs / GPUs and the capabilities/shortcomings they have

- Understanding the behaviors and quirks of the OS

- Familiarity with multicore programming

- Skillful memory management (such as making your data structures less prone to cache invalidations)

- Mastery of a low-level language (C++, Rust, whatever)

- Familiarity with build systems (CMake, SCons, etc, ... or sometimes you might have to roll your own)

Already I could see the number of contributors who would know all this stuff being pretty low. (I've dabbled a bit in graphics and made a simple OpenGL scene graph renderer and a fluid simulator, but I still don't feel like I'm competent enough...)

An engine is comprised of multiple components (Graphics, Sound, Physics, etc...). So you wouldn't need to know all of it, but contributors would need to have a clear grasp on at least one. So for each component, you would need...

- Entity System: You need a universal way to handle game entities. Implementing it efficiently requires a good knowledge of computer systems, because you need to think carefully about how you store data in the memory.

- Job System: You need a system to execute various tasks (rendering, physics, game logic, ...) simultaneously on multiple processors, so that a single game frame can finish in less than 16 milliseconds. Implementing this would require some knowledge in concurrency as well as OS concepts.

- Resource Management: You need a way to store and keep track of the game's various data stored in files, such as images, models, sounds, game objects and their parameters, settings, etc. You need to implement efficient serialization and compression for this.

- Graphics: Mastery of a graphics API (OpenGL, DirectX, Vulkan), and understanding its various patterns and shortcomings. You also need knowledge in how rendering works (which also requires some math), and nowadays a PBRT renderer (https://www.pbrt.org/) is basically a minimum requirement for modern 3D game engines.

- Physics: Lots of math and physics (Linear Algebra, Differential equations, Mechanics, etc.), and also optimization skills like assembly and SIMD (speed is critical in this area!). Fortunately many people just use already-built middleware such as Havok or Bullet..

- Sound: This is actually the most neglected part in game engine development, and it is hard to find good resources on this.

I think the people who would have the knowledge to build a game engine would be already busy working on other stuff, such as working for an AAA gamedev company (which sometimes does a lot of crunch, so they might not have enough time for open-source stuff), or a proprietary game engine company like Unity or Unreal. But I still see some hope around the edges. From what I've seen, Handmade Hero (https://handmadehero.org/, which is a livestream of making a game engine from scratch, accompanied with various education materials) is the most impressive. It tries to teach those skills needed to make a game engine to interested programmers, which I think is a crucial first step in encouraging open-source gamedev.

Some examples: for entitiy systems, EnTT is amazing. For a job system you’ve got stuff like cpp-taskflow, for physics there’s bullet, for graphics there’s bgfx or full blown renderers. Sure, these won’t solve all of your needs, but they’re a good starting point that frees you from having to do a lot of stuff yourself.

You need to be damn near Johnathan Blow levels of skill and perseverance to create a decent game engine.

Maybe you wouldn't classify him as an "elite", but I sure would.

Won't be easy for sure, neither on technical nor marketing level. Many of the successful examples took 10+ years before they got really viable. But to say it is impossible to do this for a game engine, just because no-one has done it yet, is defeatist.

Thankfully, there are millions of people who can build something at the scale of linux or firefox. Why else would it be possible for them to be open source?