Creating a Tech Tree

Does anyone know of any tools to assist in creating, maintaining and updating a technology tree?

A tech tree similar to that used by Civ, for example.

Thanks.

Hi,

what do you mean by tech tree exactly?

Say in your game the players need to research technologies to advance, before they can build certain units for example. Before they can make riflemen units they have to have researched guns, but before they research guns they need to have researched gunpowder, but before they research gunpowder they need to have researched both alchemy and chemistry, and so on.

Looking at it from the other way, once a player has researched "the wheel" as a technology, they then have the choice of whether to research milling, or carts, or chariots.

I'm looking for something that will let me input all the technologies available in the game, and connect them so that in order to research technology C, the player must first have researched A and B. And so on.

Hope that makes it clearer.

Sort of, you mean you want to build algorithms so that the users can access all these options and evolve them as their own?

I am reading for a diploma in game dev, and we're using processing, which is a java-based environment for creating animations etc... I am actually trying to create a simple sudoku game for my assignment using this. Have you heard of it or tried it out? It can create pretty complex stuff!