Designing Diverse 2D Environment Tilesets

Question

Is there an established methodology for designing diverse, quality 2d environment tilesets? I understand creating corners and borders and edges for different terrain types and materials, but I'm at a loss when considering how to make a terrain tileset that accomodates all types of concave edges and convex corners.

For example, the following Tilemap from Chrono Trigger:

They are able to basically create any shape they want with the surface tiles, and the rocky cliffs are perfectly matched.

How do you approach designing such a versatile tileset? Is there a specific set of required tiles that you need to design? Is there a basic terrain shape that should be designed that encompasses all these corners and types of tiles, that is later converted to a proper tileset?

Is it just a lot of artist work, or are there shortcuts?

Answer 1

Here is a basic pattern that you can use.

To make the tile set look good, a basic rule needs to be followed. That is each tile must tile seamlessly with all the tiles it can connect to.

Some examples: tiles E, and J must tile with themselves in all directions. Also, the top of tile E must be seamless to the bottom of tiles B, M, and N, while the top of J must be seamless to the bottom of G, H, and I.

Tile A's top edge should be seamless to the bottom of J, G H, and I. Tile A's Right edge should be seamless to the left edge of B and C. Tile A's bottom edge should be seamless to the top of D, and G. And finally, tile A's left edge should be seamless to C, F, I, and J.

Tile B's left edge should tile with the right edge of A, B, and M. Tile B's right edge should be seamless to the left edge of B, C, and N.

Etc, etc, etc. As you can see this is a long tedious list to write out, but at this point I think you can figure the rest out.

Creating multiple sets like this you can make some intricate maps. You can have a dirt/grass, and a grass/water tile sets. If you use the same grass tile in both set, you can go from dirt to grass to water seamlessly.

This same approach can be used to construct building exteriors, fences, caverns, and mazes.

Answer 2

It's a technique no doubt about it. you can use templates which are basically just checkered grids for you to paint over. There is allot of artist work involved though.

Here's an example of a tileset not unlike how the chrono trigger tileset is made.

http://www.angelfire.com/rpg/nazrpg/chips/Swamp_Village_MacBlue.png

then it's upto the level designer to arrange them in a creative fashion.

that's the best answer i can give considering how drunk i am. (it's Christmas where i am)

Edit: Also don't forget some tiles can be drawn over other tiles so additional layers or additional tilesets for each layer may be needed.

Edit: For those who cant see the link.