The objective in my game is to build a tower. Kinda like SimTower (for those of you that know about it). It is easier to sort the coords so that the topleft tile (yes, its tilebased) is coordinate 0,0. But this way, some of my testplayer said that the coordinates were confusing. Since the bottom floor on a map thats 15 tiles high became coordinate x,14. They claimed that of course the bottom floor should be 0. I went through alot of trouble trying to reorganice and rewrite stuff so this was the way everything worked. But now when I testplay, it somehow feels like it isnt as obvious that the x coordinate should be in front of the y coordinate. It somehow feels more logical that the floor/level is print first and then the "column". Any thoughts on this? Have anyone else built a tilebased game shown from the side and figured out a good way to name the coordinates?

honestly, there's no correct answer. as you discovered different people find different methods intuitive. all that's important is that you are consistent within your own game. for those people who aren't instantly ok with your chosen route there will be a brief learning curve but then your system will become intuitive to them.

-me

Vertex coordinates are only relevent from a rendering perspective, you should provide a n alternative coordinate scheme for the game player. The conversion between the two is trivial.

Dave

Internally your coordinates should be in whatever form is most convenient for your program to deal with. It's trivial to transform what the player sees to any form you like. I agree, the natural display form of the coordinates is "12th floor, (4, 6)" or something similar, but don't let that dictate how you store the data internally.

Players should never see internal data structures or have to care what form they are in.