How do you use these kind of rpg ground tileset ?

Question

Searching about some tilesets for a little RPG game, I've often found these kind of tileset :

Their structure are special, there is two upper tile and 4 others for the same material. I understand that, like that, you have all what you need to create more various shapes than simple rectangles of different sizes. But I don't get how they are used in practice. I'm talking about the two little upper tiles that are used to make some corners. for me the 4 corners are stored inside only one tile ? (hard to explain with my bad english but I'm sure you understand what I mean)

Also, do you know if that tilemapping technic has a name ? And do you kown if it is possible to use them directly in Tiled ?

Answer 1

This tileset is famous because it was used in RPG maker VX. It seemingly consists of 6 tiles (2 by 3) and it even outputs tiles in that size, but it actually handles the tileset as if it was 4 by 6:

You can then create every tile combination you need (which is 48 in most cases, source here, see the "The blob" section)

For instance, creating a tile, that has grass on the left and right side would look something like this:

Whether you unpack the tileset at start to a better format or deal with drawing 4 sub-tiles each time depends on your preferences.

However, keep in mind that most great tilesets try to make the grid-like nature of these games invisible to the player, but since you don't have much space to work with in an RPG make VX type tileset, the details will suffer.

Answer 2

These are "Auto Tiles" for the RPGMaker game engine.

While the map editor uses 32x32 tiles as a basic logic unit, the engine actually splits the tiles into 16x16 tiles. The map editor then automatically uses the sub-tiles to generate the fitting transitions. This allows the mapper to draw with just one material while the map editor automatically creates the correct edge- and corner tiles.

Example: