Yeah you readed right.
I had the idea for something really cool. But i do not want to Build a addon foe BuildCraft.
My idea is MarkerCrafting.
Sounds weird? I mean normal Crafting is nice.
but i think when you Build Structures in the World an Mark them with Markers and a Block reading the Size of it could Craft something for you when you Build the Structure for him would be even Cooler.

Actually, @Speiger - doesn't IAreaProvider (https://github.com/BuildCraft/BuildCraft/blob/BuildCraft-5.0.x/common/buildcraft/api/core/IAreaProvider.java) already gives what you're looking for? Reading the world is then just a loop withing the set boundaries.

I'm assuming that this is good enough, so closing.

Ok

You mean like the architect block reading the area inside markers, storing it in a blueprint and the builder taking said blueprint and building it?

Nope. I mean instead put it inside of a Crafting Table you place it down and tell the size with markers.

He means you "build" the recipe in the world. Then a machine reads the structure and uses that to know what to craft, instead of specifying a recipe in a crafting grid like the auto-workbench.

Is my guess of what he's talking about.

Yeah you are right Forecaster.

I think that makes a whole lot of sense. I have experiments of something like that running on 1.6.2. Gimme a couple more weeks before I can show more ;-)