The long legal battle between game publisher ZeniMax Media Inc. and Facebook Inc.’s Oculus VR Inc. ended this week in a $500 million judgment in ZeniMax’s favor, and Oculus Chief Technology Officer John Carmack was not happy.

On Thursday, he took to Facebook to rant about the trial and criticize ZeniMax’s expert witness. Carmack (pictured) particularly took offense to the witness’s claim that Oculus made a non-literal copy of source code that Carmack had written in his time at the ZeniMax-owned Id Software, the “Doom” and “Quake” game studio that Carmack himself had co-founded in the early 1990s.

In programming, non-literal copying refers to the process of duplicating a program without directly copying its source code word for word. Carmack denied that Oculus had any access to the code he created at Id, and he criticized the testimony from ZeniMax’s expert.

“The analogy that the expert gave to the jury was that if someone wrote a book that was basically Harry Potter with the names changed, it would still be copyright infringement,” Carmack said in his Facebook post. “I agree; that is the literary equivalent of changing the variable names when you copy source code. However, if you abstract Harry Potter up a notch or two, you get Campbell’s Hero’s Journey, which also maps well onto Star Wars and hundreds of other stories. These are not copyright infringement.”

Carmack further criticized the expert’s statement that he was “absolutely certain there was non-literal copying,” and Carmack noted that the witness’s full report and testimony are under seal and not available to the public.

“This is surely intentional,” Carmack said. “If the code examples were released publicly, the internet would have viciously mocked the analysis.”

While ZeniMax won a hefty $500 million judgement in its lawsuit, this sum fell short of the $4 billion the company originally sought, as the jury did not find Oculus guilty of actually stealing ZeniMax’s trade secrets. However, the jury did find Oculus guilty of copyright infringement, and it also ruled that Oculus co-founder Palmer Luckey had violated a nondisclosure agreement that he had made with ZeniMax early in the Oculus Rift’s development.

ZeniMax responded to Carmack’s comments with a statement of its own, in which the company defended its witness and the court’s judgment.

In addition to expert testimony finding both literal and non-literal copying, Oculus programmers themselves admitted using ZeniMax’s copyrighted code (one saying he cut and pasted it into the Oculus SDK), and Brendan Iribe, in writing, requested a license for the “source code shared by Carmack” they needed for the Oculus Rift. Not surprisingly, the jury found ZeniMax code copyrights were infringed. The Oculus Rift was built on a foundation of ZeniMax technology.

Oculus said in a statement that it plans to appeal the court’s decision, so it will likely be some time before the company’s legal battles with ZeniMax are truly over.

Image courtesy of Oculus, via Twitch