Nice, I'm looking forward to it!

Yep, it definitely looks cool to have a 3D random puzzle game, congrats

looking forward to see it ! (the game, and the code )

I was reading earlier in the topic and it was said that textures would be impossible to do quickly in Lua. But can't you exploit the image.copy() function? You could store each column of the texture as a TI.image, and select one of these columns depending on where the wall is intersected. Then, instead of doing something like:
gc:drawRect(x, y, xwidth, yheight)
You could do:
gc:drawImage(image.copy(columnImage, xwidth, yheight), x, y)
This is probably a bit slower than just drawing a rectangle, but I can't imagine it being as slow as drawing textures manually.

Edit: Removed extra closing parentheses

That would be a lot of TI.images

Nobody has to know if you keep them in an array, hehe

Well, Lua uses tables. You can put anything you want in a table, I'm pretty sure.

You can also use jimbauwens' ti.image compression algorithm %)

Then that's no good. Even rendering every other column, that's still 160 images. I'm not too surprised, as that was supposed to be a general purpose routine for displaying a few images here and there, not optimized for speed.

[ i'm not saying anything, okay ? ]

TI.Image will be faster in the future (very probably) thanks to [ that I really can't say ]

[ / oops what did I just say ]

... interesting