And yeah, good point about C interface being great for doing all kinds of language bindings. With some effort I'd probably manage to extract pure C interface out of my library for that purpose.

you should do that

Impressive, the code looks clean and simple yet powerful and OO which is a huge advantage for me. I must say well done. How long did it take to create the engine?

How long did it take to create the engine?

Took about 5 months by now but I've only worked on it in my spare time which I didn't have too much recently. On average probably less than 1 hour a day.