Bug #5264
NPE caused by connecting active vessel to non-active vessel klaw
100%
Description
Note: This was tested on a mod installation, but this uses parts available in stock and is very easy to re-create within 5 minutes. I also marked the platform as any as it should be platform independent, but I only personally tested it on windows.
Recreation steps:
1. Design a small rover (easiest) with a klaw on the front
2. Launch two of these rovers (going back to KSC is important, as it packs the vessel)
3. Reverse one rover into the klaw of the other rover
You should lose all GUI, and experience some physics weirdness. You also cannot switch vessels or move the camera.
Other important notes:
1. You do not need 2 klaws, there's only 2 involved for convenience sake.
2. Vessel unpacking plays an important role in this, without the packing and then unpacking the bug is not triggered.
3. Assuming you have a vessel you know got unpacked, you can re-create the bug 100% of the time.
4. Assuming you have a vessel you know wasn't unpacked (i.e. just made it), the bug will not occur when using a klaw on that vessel.
Related issues
History
#1
Updated by Hexicube almost 9 years ago
Updated by After more testing, it seems to be even more obscure than I thought, it's possible to have 2 klaws connect to each other. When this occurs, the model for one klaw head will flip to match the other head (signalling which half has the root part). Upon releasing the klaw on the half that has the root part, the NPE occurs shortly after.
It also appears that my initial speculation about vessel unpacking is incorrect, and was a fluke during testing despite repeating the test 3 times in both scenarios. However, there's still some other criteria required to trigger the bug, which may involve if KSP classifies a vessel as persistent or not.
I recorded my testing this time, so that might help in finding the exact cause. I'll have that uploaded soon.
#2
Updated by Hexicube almost 9 years ago
Video showing tests I did: https://dl.dropboxusercontent.com/u/13281778/test.mp4 (~72MB)
Sorry for potato quality and unedited footage, original file size was 5GB and I didn't have an editor that would take uncompressed flv files.
Also, I forgot to give the relevant NPEs:
[EXC 14:29:05.871] NullReferenceException
UnityEngine.Component.get_transform ()
OrbitPhysicsManager.LateUpdate ()
[EXC 14:29:05.879] NullReferenceException
UnityEngine.Component.get_transform ()
VesselLabels.DrawGUI ()
RenderingManager.OnGUI ()
In both cases the NPE occurs internally, suggesting that klaw attachment code causes something to be unset rather than the issue being with that code directly.
#3
Updated by Squelch almost 9 years ago
Updated by - Is duplicate of Bug #2881: Controlling claw dockee throws NullReferenceException, hell kraken arises added
#4
Updated by Squelch almost 9 years ago
- Related to Bug #3988: Advanced Grabbing Unit Loss of reference to parent ship added
#5
Updated by Squelch almost 9 years ago
- Related to Bug #5211: Camera gets stuck when a craft (not being the current one) with a claw attaches to the active vessel added
#6
Updated by Squelch almost 9 years ago
- Related to Bug #5098: Docking with claw when claw-equipped ship not focused breaks physics added
#7
Updated by Squelch almost 9 years ago
- Related to Bug #2753: New kraken: all ships accelerate randomly and are uncontrollable when time warp is engaged added
#8
Updated by Squelch almost 9 years ago
This seems very similar if not a duplicate of #2881
There are a number of reports concerning physics glitches, and other odd behaviour that surround the use of the claw. Thank you for your comprehensive report, it will be added to the case file on this. Please see the related issues.
#9
Updated by Squelch almost 9 years ago
- Status changed from New to Duplicate
- % Done changed from 0 to 100