It'd be as legal as the day is long. File formats aren't generally covered under copyrights, and really only when there's some kind of encryption. Straight to binary doesn't count as encryption - Gif texture compression does, not to mention that it's patented.
There's a myriad of freelanced engines using md3 models and quake3 bsps, which Carmack/id is fine with, as long as intellectual properties are not violated. I'm writing a little proggy that deals with Raven's Ghoul2, and they're perfectly fine with it - they encouraged it.
A format is just a means, not an end, and you can't really infringe upon a means ...
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ye are of nothing, and your work of nought: an abomination is he that chooseth you
There's a myriad of freelanced engines using md3 models and quake3 bsps, which Carmack/id is fine with, as long as intellectual properties are not violated. I'm writing a little proggy that deals with Raven's Ghoul2, and they're perfectly fine with it - they encouraged it.
A format is just a means, not an end, and you can't really infringe upon a means ...
------------------
ye are of nothing, and your work of nought: an abomination is he that chooseth you