Since I couldn't find the answer already in this thread I'll ask it here(A)
I've been trying to map for my pokemon game but when I test I keep running over SOME houses. I really can't seem to find an explanation:S Now I was wondering what's making this happen. I figured layer 1 is can be walked on, layer 2 cant be walked on and you walk under layer 3 but now I'm not entirely sure about that anymore... Does it has to do with the terraintags? If so, what terrain tag should be used for: can be walked on, cant be walked on and walks under? I did erase everything with the upper left 'sprite' and tried again but still no succes...
I'm really sorry if the question/answer actually is already here but I really couldn't find it(A)
Thanks in advance!
There are two aspects to tiles. The first is which layer you put them on. All this means is that one tile is drawn over another tile (e.g. a fence directly behind a house so the roof partially covers it - in this case the bottom layer would be ground, the second layer would be the fence and the third layer would be the roof). Layers are all about how the map looks,
not how the tiles behave.
The second aspect is what the tiles do. You can either walk over them (ground), can't walk through them (boulders) or walk under them (house rooves). To get to the place where you change what the tiles do, press F9 and click on the "Tileset" tab.
The two buttons you need to concern yourself with (on the right) are "Passage" and "Priority". With "Passage", an X on a tile means you can't walk through it, and an O means you can. The "Passage (4 dir)" button is an advanced version of this, used for jumpable ledges. The direction an arrow points in is the direction from which you can walk onto that tile. An arrow pointing up means you can walk south onto the tile, but you can't walk north, east or west onto it. But don't worry yourself too much with it.
"Priority" indicates whether a tile is supposed to appear above or below the player. This is only used when you can walk on (under or over) a tile, and is unimportant for tiles you can't walk on at all (e.g. boulders). A dot on a tile means the player can walk over that tile, and is used for ground/grass/water. Click on a tile and you can change the dot to a star with a number next to it. This number indicates the height, if you will, of the object - the higher in the sky that tile is supposed to be, the bigger the number should be. For example, a tower. The base cannot be walked through, but you can walk behind it. The lowest part of the tower that you can walk behind should be *1, then the next highest level should be *2, and so on until you reach the top.
Note that you can put a tile with a high priority onto a lower layer, and then put a tile with a lower priority onto a higher layer. For example, making a bridge over a forest - the tops of the trees have priority *1 so you can walk behind them and are placed on the lowest/second layer, but the bridge itself has zero priority so you can walk over it, and is placed on the top layer.
Be sure to learn the difference between layers and passage/priority. The former is for making a pretty map, and the latter is explaining how the map works (you can't walk through hedges, etc.). Have a play around.