Funny enough, JKerman never replied this thread to clarify why he wanted to decompile the DOTM maps. People are just presuming things.
There are many reasons why someone would want to decompile something, including:
- To pass the work of others as their own (which is obviously immoral and illegal);
- To learn how to create something else that matches the technical specifications of the decompiled work;
- To perform maintenance on the decompiled work, fixing problems and providing quality-of-life improvements.
- To create derivative works, usually for fun.
If I was to bet, since he mentioned that he wanted to decompile the DOTM maps because they are "designed for the Kex engine", it seems he simply wants to learn how to make the KEX-specific features work, possibly to create new maps that takes full advantage of the new features in the KEX engine. Is this immoral? No. Is this illegal? No.
Now, hypothetically speaking about the other kinds of motivations mentioned:
Maintenance modifications are simply patches. In the case of a decompiled work, it's about patching the source and recompiling it. This is nothing new in Quake: the whole concept of vispatches is about decompiling the visportals of a BSP file and recompiling the visibility data to enable transparent water. Is this illegal? No. Is this immoral? That's debatable.
As for derivative works, both their legality and their morality depends on the license under which the original work was released on.
And looking at an example... The Operation Urth Majik readme doesn't have
*any* mention of a license in it. No copyright information, no terms of use & redistribution, nothing. There's no explicit authorization, but there also isn't anything saying that it shouldn't be modified. In such a case, trying to contact the authors is advised, if they can still be reached.
But looking into the Wayback Machine...
The OUM QC code WAS released:
These are the QuakeC files compiled for OUM. Are they not awful? Some are only there for reference porpoises and others (such as !AI.QC) are junked. Source mods include IKGuns and Custents, Dissolution of Eternity and one or two odd bits and bobs from the realm of Godnozwere.
The archived download link for the OUM source doesn't work because it was on FilePlanet. Is decompiling its progs.dat "not OK" in this case? Gimme a break.