I don't like how connections are sometimes not mirrored correctly and are broken.

@NathanMikeska On what @Abiansai said that's the VERY REASON mirroring is broken in that Juno and as such is very unpleasant for a Simpleplanes player to attempt to get used too. Simpleplanes Mirroring while bugged (sometimes) and in need of tweaking is by far superior.

The part mirroring and the building system in the latest update of this game looks really nice (never played it tho) https://store.steampowered.com/app/325420/Homebrew_PatentUnknown/

EDIT: here is a link to the exact video https://www.youtube.com/watch?v=yKEzQ8bfnCk

I second @DARZAVIATION: it would be nice to choose which parts you do NOT want to mirror I keep having that -well, it's not really a problem, rather an inconvenience- that if I have to redo something on both sides of the plane and I already have a cockpit interior, I can either do both sides by hand or mirror and redo the cockpit ( all instruments and flight controls are mirrored by default. I think just having an offset to define which CENTER Or FUSELAGE parts should not be mirrored would already go a long way.

The same thing with flaps and ailerons, especially when you use funky code to mix ailerons with pitch or flaps. When you mirror your wing, you are almost certain to have to rewrite half of the code. I could live though with just the option: replace parts already mirrored/leave parts already mirrored for leaving the old wing as is even if you replace the tips.

Thanks for the feedback everyone!

A bit late so I'm sure someone has mentioned this but when you mirror your build the connections don't mirror symmetrically as well. This is very noticeable when you mirror an engine nozzle with many small parts and rotators, and the mirrored side has some parts fall off or not move once you hit play.

Another issue (visually) is that when you have some complex fuselage block mesh, with big differences between the height and width between the two faces, or with high values for rise/run, there are bumps on the mirrored side.

A suggestion I would make is to have some sort of white/blacklist for different selections of parts (like the cockpit interior) so you don't have to mirror the entire build every time. Maybe add a layers system (like in photoshop) so you can put parts in groups, then you can mirror, transform, or otherwise modify these layers independently.

Mirror around a custom axis

@NathanMikeska, I think the main addition I would like for part mirroring would be to be able to mirror around a custom axis. For example, if you were designing a missile currently attached to an aircraft, you would be able to select the item you want mirrored, then select the missile body as the mirror axis to mirror the item to the other side of the missile. This would be good for main landing gear as well; select the wheel, make the gear strut the axis, and viola. My idea for this style of mirroring comes mainly from my tinkering with Autodesk Fusion.

@SnoWFLakE0s I see. May I ask what the difference is?

@Graingy
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Direct vs. parametric modeling are two different approaches. Most modern CAD software is the latter.

@PlaneFlightX Well, uh, here.

I don't love how currently, you have to use one of the default cockpit parts. I think you should be able to select a part as the center of the aircraft, and have the user define the axis mirroring is done on.

By the way I just remembered. Anytime I did encounter part mirroring off center, and checked the center alignment and found it was correct, the constant factor was that I was using a modded main cockpit part. Either Gestours glass cockpit, or there was another one i forget who made it. It looked like a tiny ball and I'd use it as a pilots head.

Anyway I don't think any of the stock cockpit parts trigger it. I can double check the flight computer though

With more complex mechanism like my piston engine even ctrl+M wouldn't suffice, as once mirrored the connection would got mess up, so I pretty much have to just use subassembly and know that things are not mirrored.
Which things like suspension when mirrored I have to disconnect and reconnect everything to make sure things work properly.
And to trouble shoot connection is the biggest time waste for my work flow.

I never really use the feature because back when I was a phone player, there's a small chance when I use the feature, everything just get doubled and it's now impossible to clean it up.
Maybe the problem is no more but I never use it since once i switched to PC, and only exclusively use control+M

the connections just not working instead of choosing the same part on the other side (specifically with ctrl+M, my builds are too asymmetrical for the whole plane to be mirrored) is always increndibly annoying and costs me a good 20 minutes of pain per build

@Graingy nope

@PlaneFlightX Never even Tetris?

@Graingy I've only played SP, Juno, Minecraft, Transport Fever 2, and Beat Saber

Sooo I'd prefer an updated mirroring system, but I'd also like an exposed toggle in the item settings, as well as a toggle in the part groups. That way I can just up and tell the system not to mirror cockpit parts in one build, but then turn around and do it in the next. There are some times where you just have to hoof it, like when you're hardcoding instruments. I also feel like, at least on the mobile version, there is some sort of deletion or degradation that causes position drift, resulting in the center of the craft not being absolute 0, or bilateral parts having different air resistance for some reason.
I agree with most people here, though : lateral and radial, up to mayyyybe 4 way symmetry, but no more, unless you are planning juno integration.

@PlaneFlightX Ever played KSP?
In KSP there's a way to bypass the mirror limit.
Essentially, put some radial "mirrored" parts around a base part. Then, take the base part and mirror it. Move another part over the parts on the now-mirrored based part, and unless otherwise interrupted by going over a different mirror (e.g. 2 boosters) you will now have a mirror matching the double-mirrored parts. E.g. 64 from two 8s. Or, say, 16 from two 4s. 12 from a 3 and a 4. Etc.
Taking this further can very easily crash your game.
While it is fun, there kinda needs to be limits, or at the very least a warning before the game tries to render hundreds of parts at once.

@EternalDarkness About radial mirroring, I would like the ability to type in any number for the number of sections, instead of 1-6 like Juno (for stuff like turbine blades or custom fans)

Another idea I have is an approach similar to the rotation with Fine Tuner. In that mode, mirroring axis would be the first selected part of the group, which would not be mirrored. Other selected parts would then mirror around it when the command is given.

As a more or less active player of ten years, I'm quite accustomed to the old system, flawed as it is. Of course, extra options like parts being mirrored while they are being added would be welcome. In fact, that would considerably accelerate the early build process, where a bunch of large parts need to form a (usually) symmetric base of the build. Perhaps some builds could benefit from four-way radial mirroring, and certainly some subassemblies would, so I suggest adding that too as an option.

Perhaps a system in which we could multi-select parts for both nudging an mirroring would be handy. If a subassembly is supposed to appear multiple times on a build (ex. seats), you could just select the whole thing, and nudge and mirror in increments without having to unselect the assembly to mirror it.

The only problems I have is when it mirrors wrong (the mirrored parts are offset, and it's asymmetrical), and when the parts connect to the wrong things or just don't connect to anything. But other then that the current system is pretty good

I like the current SP system, but it would be nice to choose which parts not to duplicate or modify in the process, For example rotators, and with the Text Label it is not correctly duplicated, in my case, for example, with the windows made with text (they are inverted)