Advanced tiles

Im tearing my hair out I cant figure this out!

In RPG Maker, for example, when you place certain tiles down (like thick grass), the grasses image will change depending on where its positioned among other tiles, so, instead of always the same block tile, it has nice curved edges, etc.

I hope you people understand me, its a hard one to explain.

My question is, can anyone point me to a way of achieiving that automated? (rather than my self choosign the tiles)

THanks!

Check the neighbour-tiles, and keep a list of neighbour-tiles that actually have influence on your new tile.

If you have 8 rivertiles and 8 grasstiles, then when placing a grasstile at a riverbank you can check the neighbour-tile of the place where you put the grass. you could for example use the rivertilenumber and use that for the grassnumber.

You get a lot more control if you do it yourself

If you have your engine auto-detect nearby tiles and change things then theres always the chance that it will detect and change where you dont want it to do so later on