Quote: "all the tiles should be the same depth..
and chars / trees / additionals -1 or so .."
It's not completely that simple. For a base layer, something like the ground or grass that the player can never be behind, then yes I can make all those the same depth. But once you start adding layers of other objects it gets more complicated.
Ok, say layer 1 is just dirt on the ground. All tiles are set to a depth of 10. Layer 2 contains trees, make their depth 9 so they're drawn on top. Layer 3 may contain other things. Now here's the problem. What happens when objects from layer 2 and 3 are close enough that both are within the space of the character? What if a layer 2 object is placed where it should be in front of something from layer 3? This is why each tile needs its depth sorted separately and why objects likes trees that are larger than a single tile need to be a single object. Trying to map a tree that's perhaps 2x6 tiles in size but broken up into individual tiles (like I was doing) didn't work. The player could be behind the stump of the tree but his head still appears in front of the upper branches because they lie in a row of tiles above the base, thus being drawn first.
It's easier to show than explain.
I'll try your suggestion dvader and see if that clears up any other issues.
haliop, here's a picture that might help show the problem with simply changing depth based on layer. Imagine the red block is on layer 2 and blue is on layer 3. Using your method, the red block is drawn first and thus will appear behind the blue one when it should not be.
