Terrain is missing when switching to probe landed on Mun or Minmus

[undercoveryankee]

I first noticed the problem when a rover crashed on Minmus and I switched to a previous probe to get the KSPI seismic data. I've tried older saves of the same career from before the last time I was able to switch to a landed probe, with the same result. The probe appears intact, but floating in space with the skybox visible on all sides.

Log is at https://www.dropbox.com/s/ktm87kv8ksiggn7/Player.log?dl=0 . I'll work on putting together a complete mod list when I have more time to dig into it. Any suggestions on where to start?

Edited September 6, 2014 by undercoveryankee

[NathanKell]

Per the sticky try narrowing it down to the smallest set of mod(s) that exhibit the problem. That would be the best way to start.

[undercoveryankee]

Finally got some time to continue troubleshooting. I'll update this post periodically as I make progress.

I made a new copy of KSP 0.24.2 from the never-launched master copy in my Steam library and installed only enough mods to be able to load one of the probes in my save file. All mods were freshly extracted from the original downloads. It's a longer list than I would like.

Mod Group 0: Required for the test ship

• KW Rocketry 2.6c
  
• RemoteTech2 1.4.1
  
• ModuleManager 2.3.3, replacing the older versions packaged with some of the mods
  
• Interstellar Lite 12.2 and the dependencies packaged with it:
  
  • Toolbar
    
  • Community Resource Pack
    
  • Open Resource System 1.2.0
    
  • TreeLoader
    
  • TweakScale (custom package)
    

  [*]MechJeb 2.3.1

  [*]Science Revisited 1.3.1

  [*]KDEX 1.0.2

Results: Tracking Station failed to load when I clicked on it. After deleting all active contracts from my save file (assuming that FinePrint contracts were part of the problem) I was able to access the Tracking Station and switch to a probe. The original problem with missing terrain doesn't show up with this selection of mods, but I still have intermittent problems with the Tracking Station ("Fly" button remaining disabled when I click on a ship, clicking a ship doesn't select it). I suspect these glitches are due to having data in the save file for other mods I don't have.

Since the original glitch seems to be gone, I'll go ahead and add the next group of mods: the ones I find hardest to do without.

Mod Group 1: Top priority

• Active Texture Management 3-3-1
  
• FAR 0.14.1.1
  
• Procedural Fairings 3.09
  

ATM is installed with its stock configs for now. I have some local tweaks that I'll probably apply later in the process. I deleted ModStatistics from the FAR directory. I don't mind the data it shares, but for troubleshooting purposes I would rather avoid plugins that don't add gameplay.

Result: Switching to probes still works. Still getting exceptions in the Tracking Station. What seems to be the root exception is this when I try to select a vessel:

NullReferenceException: Object reference not set to an instance of an object
  at KnowledgeBase.<GetUnloadedVesselMass>m__326 (.ProtoPartResourceSnapshot x) [0x00000] in <filename unknown>:0 
  at System.Linq.Enumerable+<Sum>c__AnonStorey3A`1[ProtoPartResourceSnapshot].<>m__74 (Single a, .ProtoPartResourceSnapshot  [0x00000] in <filename unknown>:0 
  at System.Linq.Enumerable.Sum[ProtoPartResourceSnapshot,Single] (IEnumerable`1 source, System.Func`3 selector) [0x00000] in <filename unknown>:0 
  at System.Linq.Enumerable.Sum[ProtoPartResourceSnapshot] (IEnumerable`1 source, System.Func`2 selector) [0x00000] in <filename unknown>:0 
  at KnowledgeBase.GetUnloadedVesselMass (.Vessel v) [0x00000] in <filename unknown>:0 
  at KnowledgeBase.CreateVesselInfoList (.Vessel v) [0x00000] in <filename unknown>:0 
  at KnowledgeBase.OnMapFocusChange (.MapObject target) [0x00000] in <filename unknown>:0 
  at EventData`1[MapObject].Fire (.MapObject data) [0x00000] in <filename unknown>:0 
  at PlanetariumCamera.SetTarget (.MapObject tgt) [0x00000] in <filename unknown>:0 
  at SpaceTracking.SetVessel (.Vessel v, Boolean keepFocus) [0x00000] in <filename unknown>:0 
  at SpaceTracking+	.MoveNext () [0x00000] in <filename unknown>:0 

Still hoping that problem has something to do with the save referencing mods I don't have installed.

Mod Group 2: Difficulty

• Deadly Reentry Continued 5.2
  
• TAC Life Support 0.10
  
• RealChute 1.2.4
  

No change either in terrain loading or in Tracking Station exceptions. Suspect that Tracking Station exceptions occur when a part on the vessel references a resource whose definition isn't installed, such as the MKS/OKS PunchCards resource that gets added to the Comms DTS-M1 dish antenna.

Mod Group 3: Info and editing tools

• Kerbal Engineer Redux 0.6.2.10
  
• Docking Alignment Indicator 4.0
  
• Enhanced NavBall 1.3.2
  
• CrewManifest 0.5.8.0
  
• Kerbal Alarm Clock 2.7.8.2
  
• ResearchThemAll 1.1.0.0
  
• SelectRoot July 18
  
• TAC Fuel Balancer 2.0.4.3
  
• RCS Build Aid 0.5
  

Can still switch to my probes. Exceptions in Tracking Station not fully tested after this batch. The landers I've been checking the missing-terrain problem with have both been flown since the last time I reverted to the original save file and no longer contain PunchCards.

At this stage in the mod-installation process, I'm leaning toward file corruption as the cause of the original missing-terrain glitch, and I'm optimistic about my chances of continuing the interrupted career in a new copy of KSP. I think I still have two or three separate groups worth of mods to install before I'm back in action.

Edited September 4, 2014 by undercoveryankee

[undercoveryankee]

Since the last round of testing, ModuleManager 2.3.4 has been released. Upgrade that, install the next group, and continue testing.

Mod Group 4: Resources

• MKS 0.20.8 (with bundled Firespitter plugin and Karbonite). Did not install ORS because KSPI Lite's version is current.
  
• Replaced Community Resource Pack with latest version 0.1.2
  
• Asteroid Recycling Technologies 0.4.4
  
• Extraplanetary Launchpads 4.2.3
  
• EPL Karbonite conversion 16-5 (September 1)
  

Terrain was still present on switching to Minmus probe. Consistent with hypothesis that references to the MKS PunchCards resource were causing exceptions in the Tracking Station, no exceptions were observed after installing this group.

Mod Group 5: Science

• Custom Biomes 1.6.6
  
• SCANsat 7rc4. Deleted ModStatistics.
  
• Tarsier Space Tech 4.4
  

If there's a mod conflict involved, this group is where I expect to run into trouble. SCANsat actually talks to the terrain system, and it's still on an older ORS. My first time using Tarsier's telescope was between the last time I switched to a lander on my original install and the first time I ran into the bug.

No issues observed, though.

Mod Group 6: Parts, Automation, and Leftovers

• 6S Service Compartments 1.1 and extension. Skipped the older Firespitter in the package in favor of the version bundled with MKS.
  
• FinePrint 0.58b
  
• kOS 0.13.1
  
• MSI Infernal Robotics 0.18.6
  
• Procedural Dynamics 0.8.1
  
• Spaceplane Plus 1.3
  
• Taurus HCV 1.2
  

And with that group of mods, I can return to the original save and do what I was trying to do before the glitch hit.

[undercoveryankee]

After I thought everything was working again, I got a Tarsier contract to photograph Kerbin with the space telescope and completed it.

Tried switching back to a lander again and got missing terrain.

I'm experimenting with some things to see if I can get it back without a full reinstall. Once it's fixed, I'll experiment with the Tarsier telescope in a separate game to try to reduce it to a test case.

[NathanKell]

That seems like a very strange turn, yeah. Only thing I can think of is that PQS runs out of memory trying to create a new quad. OS X, right? I know that has an even lower process limit than Windows 32bit. You can try upping the scale in ATM....

If not, and you're on Linux (or can install Linux!) use Linux x64.

[undercoveryankee]

That seems like a very strange turn, yeah. Only thing I can think of is that PQS runs out of memory trying to create a new quad. OS X, right? I know that has an even lower process limit than Windows 32bit. You can try upping the scale in ATM....

If not, and you're on Linux (or can install Linux!) use Linux x64.

OS X. If it was just a memory problem, you'd think that reverting to the same save and the same mods from the last time it worked would fix it. It doesn't make sense that once this glitch has been triggered, it survives everything short of a clean reinstall. At least now I have the steps that worked to fix it written down.

I'll be back (probably on the Tarsier Space Tech thread) if I can find a simple test case.

[NathanKell]

Unity/KSP use garbage collection; that means that the memory state will not necessarily be the same each time you load that save. But yeah, it's not a certainty it's that...