Using the Root Tool

[Tery215]

Purpose:

Create subassemblies from objects that previously were not subassemblies.

It looks like this:

For example, one would attach this craft

To this craft:

If one were to choose to use the first craft as a subassembly, they would follow these steps:

1. Select root tool (shown earlier)
   
2. Click on part with desired attachment node twice
   If that doesn't work, click on another part and then on the part with the desired attachment node.
   
3. Return to "Place" mode
   
4. Enable Advanced Mode in the right-top corner
   
5. Open "Subassemblies" tab
   
   
6. Shift-Click on the new root part, then drag to subassemblies drop zone. Save subassembly.
   

The subassembly is now created.

To attach it to craft 2, keep the subassembly folder open. Click on the subassembly that was saved previously, and drag to attachment node.

Edited December 24, 2014 by Tery215

[Vanamonde]

It's embarrassing to admit, but I still have no idea how the root function works. But I followed your steps, and it worked. Thanks!

[Capt. Markie]

OK, so how does one "un-root" a root part?

[sumghai]

OK, so how does one "un-root" a root part?

Presumably, choose another part as root.

[Azimech]

I never understood why the second click is needed. Always works for me though.

[jeancallisti]

Additional info in some post I've read on the Internet:

Quote

 

About the root

The root part is the parent of all the other parts. It's like the grandpa in a big family tree of parts. Each part placed is a child of the root, or a child of one of the children of the root.

If you have three parts, the first part you place is the root, and the second is the first child of the root. The third is either the second child of the root, or a child of the first child. As you place more parts, more branches are made connecting children to children to children and finally to the root.

About sub-assemblies

If you take a part that has children off of the main assembly, then this is a sub-assembly. The part you grabbed on to and pulled off, that all the other parts are still connected to, and so also come off, is the parent of that sub-assembly, and is like the root for those detached parts.

When you save sub-assemblies, that parent that you pulled off is the root of the sub-assembly, and is where that sub-assembly will attach to another main assembly. Only that part's nodes will be available to attach to the main assembly, no matter what other nodes are available on the children of that parent.(a little-off topic, but good to know)

About the need for two clicks

When you use the Change Root tool, you first select the part you want to be the first child, then the part you want to be the new root. The first child is then parented to the new root. It does not move the parts physically, only re-arranges how the program tracks which parts belong to which other parts, up to the root.

If I had a real tree that I could use Change Root on, I would first select the roots, then a branch. The tree would try growing leaves underground, and drink nutrients through that branch, since it now thinks the roots are branches, and that one branch is the roots. Not a happy tree, but maybe useful.

 

Also, these: 

 

[Temstar]

I still don't see why there's a need to identify first child. Wouldn't you just have every part that's attached to the new root (via either radial or node) be the first generation children of the root? What's so special about this first child?

[ExplorerKlatt]

If I understand it correctly, it determines which way "up" is. Typically, in KSP, a rocket is built top down. If you don't determine the first child, what happens when the new root has more than one direct child attached? 

[Temstar]

49 minutes ago, ExplorerKlatt said:

If I understand it correctly, it determines which way "up" is. Typically, in KSP, a rocket is built top down. If you don't determine the first child, what happens when the new root has more than one direct child attached? 

There's no such concept as "up" in the editor, your navball orientation depends on orientation of the root part or the first "control from here" part.