yep, prissi, and that's what I already implemented. the problem comes from the situation uploading the textures each frame consumes too much CPU and PCI bandwidth, so I have to create a texture with all possible tiles and upload it first, and re-use it on all frames. To make this I added some code to calc_water_level anf just uploaded all those images.
This has already been implemented and it works perfect, boosting performance.
the problem is now i want to do the same with slopes and ways, and can't see a good place in code to locate wich are those images. about slopes i was thinking generating them from textures prograatically like climate tilles are now, and do the code for simutrans 2D too, auporting doble heigjt. but how to register just way images?
written from my phone, this post might have errors