Tutorial: how to use the "root part" tool

[jeancallisti]

The "root part" tool is the tool in the Vehicle Assembly and Planes Hangar, next to "rotate", "offset".

I've been looking all over the Internet how to use it (not what it does, just how to use it), and it's always super confusing and badly explained. I've been raging for a long time because of this. One of the reasons it that there is some confusion from the forum people with the old SelectRoot mod, which was doing the same thing, but differently. People still explain how to use root part as if they were dealing with SelectRoot.

So here we go.

What is the root part?

This is the best and simplest explanation I've found: http://forum.kerbalspaceprogram.com/threads/104700-What-s-the-point-of-the-first-step-of-re-root-tool?p=1626941&viewfull=1#post1626941

Basically, every ship/rocket/assembly starts from a single part. That's the one part onto which you click to move the entire rocket around with the mouse. The root part tool allows you to change that part.

The root part becomes very important when you start working with subassemblies, because the KSP gui goes all crazy when you try to attach that assembly to your main ship. It will try to attach it starting from the root part. So if your root part is, let's say, a docking port, then everything goes well. But if your root part is, let's say, the pod, then it might not attach the way you want it to attach.

How to use the root part tool (simple solution)

Many people say "just click on the new root part". FALSE. Kerbal's gui tells you to click on two parts, and it's extremy (extremely!) confusing.

So I'm not going to go into the details, I'm just going to explain the simple solution:

1) click on the "root part" button

2) click on any stupid part that touches your new root part.

3) click on you new root part.

4) Nothing happened, apparently. But if you did it correctly, now if you click on the "place" button (to go back to normal edit mode), and if you click on your new root part, that's now the part that you may use to move everything around.

If you screwed up, and if that click messes up with your build, never forget that you can press Ctrl+Z to cancel your last action.

If someone feels like they're able to explain why you need to click on two parts, and what part should be chosen, then feel free to do so, but please do better than the people before you, who either misunderstood the question, or explained something enirely different.

Edited September 5, 2015 by jeancallisti

[MGM]

Oh, I commented on that in another post: http://forum.kerbalspaceprogram.com/threads/104700-What-s-the-point-of-the-first-step-of-re-root-tool/page2

The two-step does work on subassemblies, but you have to have the subassembly selected so you're dragging it around when you click on the root tool.