Heis ppl. I have this question. Up to what level of programing we can go with LUA? For example: Supose a game. The game has a rendering system, on the top he has the model system, then the entity ancestral, on top we had the entity we are programing and in top of that we have the proprieties. This falows that structure of a piramid that we can do when designing a software. My question is in what level of design end''s the c++ and stars the LUA? Ok, the rendering systems I doubt we could do that on LUA, the model systems too, but what about the entitie ancestral? Is that c++ or LUA? And for the other objects?

This is completely on you to define.
You can use Lua on the completely low level stuff for rendering or only as small scripts controlling entities or entity events.

Just make a good tradeoff between script control and speed. Writing your render loop in Lua will not make it faster.

I once tested lua in an experiment, which had all entitied controlled by scripts (XXX_Update, XXX_Collide, etc..).
It worked fine for the small count of entities i had, but i
wouldn''t use that approach with a full scaled 3d engine.

Ok, thanks!!