Fixed MP: CV torque can become unresponsive to clients [7800]

Updated with demonstration ship attached/new instructions. Ready for review!

Build: v1.4 3259
Mode: Survival & Creative (All?)
Mode: Dedicated Server

Reproducibility: Always (but only under very specific circumstances, read on)
Severity: Moderate

Type: Thrusters/Torque

Summary: It's possible for a player/client to lose all Thruster Torque on a CV, while another player can pilot the ship just fine.

Description: This bug seems incredibly fiddly, random and hard to replicate. It took hours of work to isolate what factors were involved and how to set up a test case with minimum steps that should lead to 100% reproduction ability. I've been experiencing it for about a year now and nothing would please me more than providing enough information that it can be tracked down and fixed.

When this bug occurs, thrusters that were off when a player enters a playfield will not respond for the purposes of turning the ship. Movement still works fine. If a CV had all thrusters off, that player cannot rotate in any direction (pitch/roll/yaw). If all were off except Up and Down, then only Pitch responds, and so forth. HVs and SVs appear to be unaffected.

Other players that didn't enter the playfield while Thrusters were off can still pilot the ship normally. The affected player(s) entering the playfield again or rejoining with the Thrusters switched *On* corrects the issue for them, allowing them to turn the ship again. Note that RCS units seem to continue to be responsive and turn the ship normally, even if they were also turned (and even remain) off.

I've observed this happening during game play with two of my own CVs, and also the built-in CORE Sparrow, but between my blueprints and the stock ones I could only find a single CV blueprint that both myself and another player could reliably reproduce this bug with in a test environment: My own design, a T2 CV that I designed for deep space exploration and mining back around A12. I named her the Calypso. Some of the hull exterior and the warp drive compartment drew visual inspiration from the beautiful MSS Ambry-CT. The rest of the ship is my own crazy idea. I'm attaching it to the thread now for testing.

Although we'll use Creative as the reproduction environment due to how shy this bug is, keep in mind that it isn't limited to Creative mode. I'm positive I've experienced this in Survival games at least 6 times or more. It's gotten to the point I just don't switch Thrusters off any more on CVs.

Steps to Reproduce:
1) Start and join a new Creative Coop game/dedicated server. Climate and Empty World don't matter. If you want to skip Step 2, just pick Arid and Empty World = No.
2) If you set Empty World to Yes and have no starter base, -OR- chose White Canvas and do have a Starter Base: Use the Item Menu to fetch any Starter Vessel Block (HV, SV, CV, just not a BA) and place it down anywhere nearby. This step is important to reduce the chaos factor and make sure the CV torque breaks.
3) Spawn the attached capital vessel (Calypso) nearby and use the Panel to deactivate all its Thrusters.
4) Either use god mode (do NOT spawn another vessel for travel) and leave, then return to the CV's playfield, or disconnect and rejoin the server in the same playfield.
5) Reactivate the Thrusters and try to steer the ship. Thrusters will move the ship but not turn it in any direction.

At this point, if you leave the Thrusters on and re-enter the playfield again, the ship will resume working as normal. If you turn them back off and re-enter, the bug appears once more. It seems you can also pluck one or more thrusters off the ship (small, medium, doesn't matter) and the bug stops being reproducible.

I also tried removing all 8 medium thrusters (4 face forward, 4 back) with 4 large thrusters, and in this case the bug didn't go away and torque remained unresponsive.

I tried copying and pasting all the thrusters back into place, replacing them all manually and resaving the blueprint - nothing seems to prevent it from happening again in the repro scenario above.

A big thank you to both @Darinth and @Nimmanu for their assistance verifying the reproducibility of this bug in their own games.

 

Repro on this definitely isn't an always. I keep my CV thrusters off as part of my power save switch, I had no such issues yesterday when I logged in. I also just tried to repro both in on my dedi survival and a single player creative.

 

Thank you, Darinth. Updated repro status. So far it happens to me every time with the same various tested CVs and in both planetary and space playfields. I'll try using more CVs and see if the presence or lack of any particular systems, like RCS, may be a factor.

EDIT: RCS units continue to allow turning (even if they're also powered off when entering the playfield), this seems to be the cause of the discrepancy. The two CV blueprints I was testing with did not have any RCS units. Can you confirm whether the CV you were testing with has RCS units or not?

I've been experiencing this since around A12.

EDIT #2: Thanks to your observation, I realized I had tested SVs that DID have RCS units. Further testing shows that they seem to be behaving correctly with or without RCS units, although the behavior of deactivated thrusters seems to differ between CVs and others. Not sure why.

 

Just went and double-checked. The ship I spawned in for the creative testing is the Albatros, which shows no torque from RCS and I didn't see any in the device list. The ship I used on my dedicated server also has no RCS, and I've attached it to this post. It's still a work in progress, but it's fairly functional.

 

Interesting. I also can't reproduce this with either the Albatross or your ship. I noticed that both of these have Large Thrusters, and neither have Small Thrusters like the 3 ships I have consistently behaving this way, but after removing or adding them to different ships they don't seem to be a factor in this behavior.

I'm curious, since these 2 ships behave the same way for me as for you, can you reproduce the bug behavior with the CORE Sparrow stock blueprint?

EDIT: Further testing still in progress. I've discovered some interesting and related things. Check the update edited into the top of the first thread. I'll post again when I've finished taking notes.

 

I've edited the original post with new information and reproduction steps. This was a really tricky one to track down. It seems something in my original test environment got really lucky and allowed me to reproduce this consistently with 3 different CVs, but I have never been able to get that to happen again since Darinth tried to replicate it and reported no issue.

I have, however, been working hard to determine a specific set of steps in a new game that trigger it every time, and I think I've finally got it down. Using these steps I can replicate this in a new game/save session every time now, and not just for myself, but also for another player on their own PC. I would greatly appreciate if anyone would be willing to take a few minutes to verify that they can reproduce the bug using the included blueprint and carefully following the steps outlined in the original post now.

Happy to try to provide any further information or testing that might help narrow this one down further, but I've exhausted all ideas for now.

 

I was able to duplicate this consistently with Calypso.

Directional control existed to a degree:

Up and down: Yes
Strafe side to side: Yes
Forward and back: Yes
Pitch and Yaw (roll): No
Turn right/ left: No

 

For whatever it's worth, I can confirm this no longer seems to reproduce in the experimental branch.

I'm curious, was there something specific about the structural design of this blueprint that made this show up much more often? Or was it just happenstance due to some odd thing like the placement order of blocks, number and type of thrusters...?

Anyway, thank you very much for all your work.