I don't want to venture into the legal question, because I think it depends on the details of exactly what they changed compared to the original, and how much human creativity went into those changes, and I don't think we have those details.

But, most engineers/PMs/etc don't have a good understanding of copyright law – it wouldn't surprise me if the authors of that blog post just slapped "Copyright Meta" on it by default because they are used to doing that, and aren't thinking at all about technical legal questions of copyrightability. Furthermore, it isn't really their job to think about those questions – that's what companies employ lawyers for – and I imagine the lawyers likely think that asserting copyright over the uncopyrightable has minimal negative consequences, whereas failing to make that assertion can work against them if it ever becomes the basis of a lawsuit, so better just tell the employees to slap a copyright notice on everything.

I once contributed (on my employer's time) to a FAANG open source project (I'll avoid saying which project or FAANG because I don't want to publicly embarrass anybody). I added a brand new file which I'd written from scratch; I copied the copyright/license notice from one of the existing files to the new one, but I changed it from "Copyright [FAANG]" to "Copyright [MyEmployer]". The FAANG employee who ran the open source project objected to that – "why did you change the copyright, everything in this project is copyright by [FAANG]"– the project didn't have a CLA, by the way. I told them they were wrong about the law, and if they didn't believe me, ask their own lawyers – and maybe they did talk to them, because they dropped the objection and ended up merging it, complete with my employer's copyright notice. So even FAANG engineers can fail to grasp the basics of copyright law.

A photo of a public domain painting is only in the public domain if the photograph wasn't distinct enough from the photographed work. Rendering requires a number of "artistic" choices so I doubt that precedent would apply here.

Here is a better explanation from your Wikipedia link:

> Bridgeman Art Library v. Corel Corp. [...] which ruled that exact photographic copies of public domain images could not be protected by copyright in the United States because the copies lack originality.

> Rendering requires a number of “artistic” choices so I doubt that precedent would apply here.

I wouldn’t speculate on what might fly in court, but while some rendering can require artistic choices, it’s certainly not a requirement for all renderings, and more importantly, the specific renderings in question here are very low on the artistic choices scale; they’re generic screen-captures meant to demonstrate the library’s functionality, not carefully rendered imagery. The Bistro scene is instantly recognizable, and the view is generic and similar to many existing renderings, and lower quality than what you get if you web-search for “bistro scene render”.

I will speculate that it seems likely that Khronos slapped the copyright notice simply because they got the images from Meta, and that Meta made them of this scene specifically because the scene has an open license, and Meta had no particular intent to assert copyrights. I bet this is only a CYA by Khronos, and not even a question of precedent. That said, I guess maybe I think it lands closer to Bridgeman v Corel than you do.

What I meant by rendering is not scene staging: lights, camera position, etc. what I meant was that when you implement a rendering engine, you need to make artistic choices. Like when you implement a lightening system, there are a number of decisions you need to make about how it works. Each decision changes how the final lighting looks. That’s why you can pretty much tell when a video game was implemented using UE3: everything is super shiny.

This isn’t a rendering engine, it’s a library layer that just provides an interface to OpenGL, Vulkan, Metal, etc. The pics in the article look like OpenGL renders, and this library is not really making its own “artistic choices”.

Even if it was a rendering engine, having worked on rendering engines for both games and film, I’m unconvinced by your argument. In fact, the goal is typically to avoid baking artistic choices into the engine. The goal is usually to represent the choices made in the scene and the staging by the actual artists faithfully without bias. Sometimes there are some identifiable styles that emerge out of the technical limitations of an engine, or occasionally from unique technical features. It’d be a stretch to call those artistic choices. There can also be uniquely stylized engines that make unique artistic choices, and they’re pretty niche so I can’t even name one off the top of my head, but this library by Meta definitely isn’t one of those.

And again, if you look at the two specific images in question in the article, there really aren’t any particularly unique artistic choices there, neither in the rendering engine nor in the staging. They look like screenshots of an OpenGL render of the CC licensed Bistro, using a camera view and lighting that is similar to thousands of other shots of this scene.