I need to be able to efficiently render a tilemap which can be constructed this way:
There is one non-transparent base layer
Then there can be 3 partially-transparent layers on top of it. Each tile consist of tile texture + alpha texture.
I do not know much about rendering tile maps but I do have some knowledge of using shaders in Unity. I know something about control texture technique and about texture atlases.
I have about just 50 textures so I could easily put them all in one texture atlas 2048x2048 which most devices (even mobile) support today.
Also I have one animated texture (sea), so chosen approach should consider that.
What I don't know is how I should generate my mesh (two triangels per tile?) and which data exactly I should pass to my shader and how to do rendering there. Everything considering that there is 4 textures + 3 alpha textures per tile and they should be strictly ordered when rendered.