VAB/SPH Glue Option - Solution For Multiple Docking Ports

[petlahk]

I've been playing KSP for years now. I got it very quickly after it came out and I've only very recently started building complex space stations.

In my attempt to build a rather complicated space station for USI life support I've noticed that it is nearly impossible to double or triple, or quadruple dock docking ports. Yes, I am using stock docking ports
The first problem with this of course is that if one docking port is docked to another than the entire vessel counts as docked and this prevents any other docking ports from finishing their dock. But, that isn't the issue this particular suggestion is about.

Please, could we have a  "glue" option? Or at least a better root option.

In my attempt to build a complicated space station I've noticed that it is really hard to get three docking ports on multiple arms to be the same length apart. Particularly if these are attached across multiple pieces and are different sizes of ports (In my case SRs versus regular ports). This makes it practically impossible sometimes to get docking ports lined up in such a way that multiple ones even stand a *chance* of docking together.

The simplest thing to do here would be to give a simple tool to "glue" one part to another. The tool would allow us to stick one part that might not be the right length in position then "glue" it to the part you need it attached to in the VAB/SPH such that a player could launch the intact piece and *know* for certain that the docking ports are in the right place.

Currently, the best possible is to either twiddle around with the sliders which doesn't always work, or to do this:
 

Spoiler

This is clearly not going to work. Sometimes the increments on the slider snap are too large. Sometimes too small. And sometimes no matter how much you tweak it by hand it's just not gonna get to the right place.

This leaves the next best thing for me to do to put that front docking port on the docking port on the central hub and somehow connect it to that top module. But this is impossible with the current tools. At least, impossible for what I am trying to do. Yes, I could get the parts in the top of the image connected together rather easily, but then the ports on the bottom truss section would be the wrong length and out of position themselves, which doesn't work for my station design.

So, as I said, the next best thing is to do this:

 

Spoiler

Which doesn't work. It doesn't work because it is literally impossible to connect those three pieces to the middle module on the right. No matter what combination of root trickery I try to do. Same goes for the other hub on the far right.

This issue has plagued me not just on this station, but also on a simpler design as well. I had a design for a nuclear rocket engine assembly that I would launch with a space plane in sections. But in order to get the whole thing up in the space-plane I needed to break the 8 small fuel tanks off and launch them separately. And in order to ensure structural rigidity I attached two docking ports to each of the small fuel tanks. Which, again, was very tricky to do because there was no way of knowing 100% for sure that the docking ports would be aligned.

Forum threads when googling this issue all inevitably say "If you need structural rigidity then use KAS/KIS struts". This would work for me as I'm playing with mods already. But there are plenty of players that play stock only, and the lack of functionality to attach that set of parts to the right can really throw a wrench in complex docking port design.

So, the proposal pet, get to the point.

Add a better glue/root function. Let me move the set of parts in the image to the right. Preferably a button hold and two mouse clicks. Like so:

 

Spoiler

All the tool would do is switch the attachment of the highlighted part from the docking port on the left to do the module on the right. This way I could align the parts the way I currently have, and then ensure that they're connected so as to transport them as well.

Please, and thank you.
Best Regards from a longtime player.

[jjansen]

Do you realize that you can change the offset slider from snap to pixel-by-pixel?

I've built several space stations and craft with multiple simultaneous docking ports and I've never had a problem aligning ports, even prior to the ability to even offset parts.

Furthermore, I don't understand what the issue you're having with re-rooting is. Your design looks perfectly centerline symmetrical, so why on earth are you building it part-wise on both sides and not just cloning the far side, which seems to have perfectly aligned anyway?

I don't use your mods, but I could quite easily mock up a tutorial in vanilla to show you how to do this if you want.

(Also, in terms of station building, you'd be much better off putting docking port JRs on the CoM of each component and using a monoprop tug system to build them into place as you want.)

Edited June 2, 2018 by jjansen
added link as proof

[petlahk]

26 minutes ago, jjansen said:

Do you realize that you can change the offset slider from snap to pixel-by-pixel?

I've built several space stations and craft with multiple simultaneous docking ports and I've never had a problem aligning ports, even prior to the ability to even offset parts.

Furthermore, I don't understand what the issue you're having with re-rooting is. Your design looks perfectly centerline symmetrical, so why on earth are you building it part-wise on both sides and not just cloning the far side, which seems to have perfectly aligned anyway?

I don't use your mods, but I could quite easily mock up a tutorial in vanilla to show you how to do this if you want.

(Also, in terms of station building, you'd be much better off putting docking port JRs on the CoM of each component and using a monoprop tug system to build them into place as you want.)

Hey, jjansen. Thank you for replying.

This is the issue with just re-rooting it:

 

Spoiler

I can't just re-route it because those hubs in combination with the trusses are the wrong length. Also, they're made out of tubes and the docking port seniors. There's also the added issue of the ends of the habitation modules (that center module) having several different snap points. One of them being flat, the other being conical. Still, yes, this is solved with the slider. But I just realized that this wouldn't entirely work because the conical bit extends out in front of the docking port, so it would be clipping. And thus, on launch, would be colliding.

I can't move the docking tube+port forward on the left section because the left section + trusses is already in orbit and the right section and all the hab modules is the new module. I could scoot the docking port forward off of the flat attatchment point, but this then adds an ugly gap in a different place. Which I guess could be solved with a little bit of clipping, but, again, isn't that pretty.

I can scoot the tube+docking port forward to the exact spot on the left hub as this would then be the correct placement, but then I run into this issue:
 

Spoiler

Which is impossible to solve by re-routing. Obviously I can't attach the tube + docking port to the center and then launch it because then it would be clipping with the right hub instead. And I spent the better part of 4 hours trying to figure out a way to re-route it with a fancy pattern of clicks.

Now I realize that it would be possible to instead attach the thing to the right hub then scoot the tube forward and that would work. But, again, I'd prefer it if I could get them exactly aligned for the sake of performance and ensuring that they connect. And, yes, I did re-route the whole structure to the right hub.

As for not cloning the far side. The two top and bottom modules are different parts. The top is a USI-LifeSupport Medbay, and the Bottom is another Kerbitat which is configured for a different purpose. Besides, the cloning wouldn't actually help solve the issue. Again, for many of the reasons stated above.

As for tugs. I do use RCS tugs, but I use large ones with a big docking port on one end, a small docking port on the other, lots of RCS, a large reaction wheel, and some other stuff. They provide much better control between the RCS thrusters on each part and the reaction wheel.


 

[jjansen]

I think you found your solution. I don't think this warrants resources to change it that could be used for anything else, like a PAPI indicator on the runway, for example.

Also, the tugs are in pairs. Look under the fuel tank. Around the COM, you CAN NOT get better control.

Edited June 2, 2018 by jjansen