YouTD is a TowerDefense for Warcraft3 (if you don't know what either of these names mean, then you are wrong here). Okay, there are 1k+ Tower Defenses out there, so what is special? The special thing is that YOU will have the chance to take part in its creation!

You might ask:
"How is this possible, is this just an open source map where everyone can alter it and then just send the altered version?" The answer is of course NO.
The idea is that you can download a small map that allows you to design one tower or item for this TD. When you are finished, you use the program GMSI to serialize the tower's data and upload it to the YouTD webpage. There, people will discuss your tower and if they (and especially the admins) like it, your tower will be put in the next version of YouTD.

The next thing you might ask:
"Okay, so you just let us make towers and lean back?" The answer is again NO.
First thing I have done is providing a nice TD stub with nice environment and creep waves with random special abilities. All the other stuff that is no tower or item will be perfected by me, that is also a big bunch of work.
Second writing a GMSI script for Tower serialization was no trivial part of work.
Third, an best, I have written an API that allows you to design wonderful tower effects with just a few lines of code.

If you still read this, you are probably tinkering with the idea of creating a tower or an item for YouTD. This introduction will show what challanges will await you and how easy it is to create complex tower effects with only a few lines of code using the YouTD API.

If you decide to create a tower, you will have to read this HowTo completely, or at least the parts which matter for your tower! So, if you are too tired to read so much text, then skip your idea. I don't want to be asked questions a thousand times that are already answered here.

What skills do you need?

• Good knowledge of wc3 gameplay, balancing & abilities
• Verve, a lot of it! (Especially the verve to read and fully understand this document)
• Good JASS skills, include a tiny bit of vJASS. If you have no idea about vJASS, things aren't lost yet. This HowTo will tell you what vJASS stuff you need, but you must have the will to understand it. If you are not so fit in JASS, maybe YouTD is the point where you can learn JASS from fast, by checking other people's towers and seeing in how few lines a neat spell is done. If you are still one of those "GUI is cool" guys, imagine this spell: "A chainlightning that stuns every unit it hits(!), has a 50% chance to do critical damage(!) and does +100% damage to undead. If it kills a unit it will grant 2 gold extra bounty." By using JASS and the YouTD API, you can code such a spell with about 10-20 lines (!) of code. Now give me a GUI trigger (without custom script, cause custom script IS JASS) with less than 100 lines that can do that. If you can do it, you are quite good.
  If your JASS skills aren't good but you have a great tower idea, consult the forum and ask there if someone wants to implement your idea! If your idea is really great, there will be people who want to do it.
  I will require you to write clean, efficient, leakless, commented JASS code, otherwise such a big project has no chance, I am afraid. However, YouTD will offer you a great API that makes complicated things very easy. But you must have the will to learn this API, then you can create wonderful towers with just a few lines of JASS code.
  If you know some JASS but no vJASS, check out geX's vJASS Beginner's Tutorial. It will tell you the tiny bit of vJASS you need for YouTD.

What programs do you need?

• Warcraft 3, including the expansion The Frozen Throne
• A vJass compiler like the Jass New Gen Pack
• The latest GMSI version (included in the developement package)

Appetizer: What things does the API offer

• A high end projectile engine
• Suberb dummy handling
• Advanced Damage and Critical spell handling (Ever seen a chainlightning crit?)
• Triggered Buff and Aura handling
• Multiple autocasts per unit
• Other small systems that ease the work for you

So, if you are now interested read on!

This document is divided into chapters that show you the different things you need to do. I know it is long and you don't want to read it for hours. The chapters start with the basic stuff and then go deeper and deeper into the matter.
So, as soon you know all the stuff you need for your tower or item from that chapter, just skip the rest and only read it when you need it.

The next chapter will narrate the creation of towers, items will be stated in the chapter afterwards.