Missing Parts and Save Files

[almagnus1]

So I was in the process of pulling out Remote Tech from my save, and loaded up my save, and about half of my vessels (including a space station) were eaten by the kraken on load, as the game failed to load most of them due to missing parts.

Unfortunately, these were all crewed vessels.

So after closing down the game, restoring Remote Tech, and loading it up again, I saw that all the missing vessels were truly gone.

This leads me to my question: Is it possible to engineer in better safeguards with crafts that are missing parts so when the above happens (or CKAN derps after a mod's folder structure changes), we don't irrecoverably lose craft?

[genericeventhandler]

I don't play anymore without the S.A.V.E auto backup  so I can revert if a mod wipes out a craft.

When it does I make a note of which crafts have been deleted, reinstall the mod then send an engineer to detach the parts and return them to Kerbin.

[almagnus1]

10 hours ago, genericeventhandler said:

I don't play anymore without the S.A.V.E auto backup  so I can revert if a mod wipes out a craft.

When it does I make a note of which crafts have been deleted, reinstall the mod then send an engineer to detach the parts and return them to Kerbin.

What's the link to that mod?

Sometimes it's not that simple, as (in the case of remote tech), I would need to adjust a whole legion of satellites, which is a lot more work than one would think (get engineer to rendezvous, do work, goto next).  A UI based way to easily remove the offending parts (or replace them with compatible parts) would be ideal.

IMO, the game shouldn't delete invalid craft from the save if they aren't loaded to begin with.  Instead, the game should leave the craft there so players have an opportunity to fix the error, rather than risk losing craft when something with mods go sideways.

[Yemo]

For remote tech, you can try to just remove everything except the "Parts" folder.

[swjr-swis]

1 hour ago, almagnus1 said:

What's the link to that mod?

S.A.V.E.

[almagnus1]

22 hours ago, Yemo said:

For remote tech, you can try to just remove everything except the "Parts" folder.

The issue here isn't the removal of the mod (as Remote Tech was used as an example, really), but the base behavior of the game because it's very unforgiving when parts aren't there between loads.

The same happened with the latest UKS update because CKAN had a bug (which should be fixed now) where CKAN didn't properly install UKS due to changes in the UKS file structure, rendering a mod uninstalled despite the user thinking it was.  S. A. V. E. is a valid workaround for the time being, but it's not a long term solution, as KSP itself shouldn't delete craft just because there's an invalid part on them.

[swjr-swis]

2 hours ago, almagnus1 said:

KSP itself shouldn't delete craft just because there's an invalid part on them.

Hmm. There's a bit of a catch 22 with this one.

I would like there to be a little more error tolerance for this too, and naively I think of the game having some sort of generic placeholder part that is used instead of the missing or corrupted part. The problem is that the properties of a single part can completely change the properties of a ship, in some cases even when unloaded and 'on rails': eg. how many of which resources are on it, uses electric charge or not, participates in a relay network or not, makes a craft controllable or not, etc. In other cases it's the properties of that one part that may make it viable or not explode at all.

The game cannot simply make an assumption on any of these things, and since some of these properties are checked and processed every single time step in the game, or at scene or focus changes, they can't be left undefined. And that's exactly the problem with 'invalid parts': the definition at load time is missing, be it due to a missing mod or a corrupted file or patch somewhere, so the game knows nothing about what the part does for the ship, resulting in the entire ship being in limbo.

Not sure how that could be solved properly.

[almagnus1]

2 hours ago, swjr-swis said:

Hmm. There's a bit of a catch 22 with this one.

I would like there to be a little more error tolerance for this too, and naively I think of the game having some sort of generic placeholder part that is used instead of the missing or corrupted part. The problem is that the properties of a single part can completely change the properties of a ship, in some cases even when unloaded and 'on rails': eg. how many of which resources are on it, uses electric charge or not, participates in a relay network or not, makes a craft controllable or not, etc. In other cases it's the properties of that one part that may make it viable or not explode at all.

The game cannot simply make an assumption on any of these things, and since some of these properties are checked and processed every single time step in the game, or at scene or focus changes, they can't be left undefined. And that's exactly the problem with 'invalid parts': the definition at load time is missing, be it due to a missing mod or a corrupted file or patch somewhere, so the game knows nothing about what the part does for the ship, resulting in the entire ship being in limbo.

Not sure how that could be solved properly.

I'd rather have the game flag give you a UI that gives you a choice on the matter to either delete the vehicles and continue (basically what it does now) or abort the load and dump you back out to the main menu WITHOUT altering the save data.

That way the vehicles don't get screwed with, and the player has a chance to fix the error before loosing crewed vessels, stations, probes, and/or bases that may have taken a lot of work to play.  The losing of things is the part that's just bad UX, and should be avoided, especially since KSP allows for mod support.

[wasml]

In your second scenario, If the user chose to abort, a log of the offending craft and missing parts would be very helpful in recovery.