Creating and using seamless texture sets

[Karro]

Even stock gimp has a (poor quality) command Map->Make Seamless.

But if you google for "seamless tile tutorial" you get tens of thousands of hits.

There are also loads of dedicated programs just for creating seamless textures, but again, YMMV.

-Rob A>

Thanks, plus I found the one Redrobes referred to in the post above.

Now... maybe a more complex question (or maybe just more stupid):

Firstly, what's the maximum size of an image like this?

Secondly, is it possible to make, say, only the top and bottom tileable, so that you can tile a column, vertically, but it won't tile horizontally...?