Dragging Along
Good afternoon, Kerbonauts!
This week, we're working on many of the same bugs we were working on last week (one aspect of our increased transparency is likely to be that you get to share in the joy of waiting for the oven to go "ding"). We did see some encouraging movement on a few items, but I'll keep the original ten bugs on the list until we've got bona fide QA sign-off on them.
[h3]Bug Status[/h3]
For most of this list, investigation and/or testing is ongoing. Areas that saw significant change have been marked in bold:
- Vehicles in stable coasting orbits sometimes experience orbit instability/decay - Status: possible fix in progress
- Trajectories change when vehicles cross SOI boundaries - Status: fix in progress
- Certain inline parts cause aerodynamic drag numbers to spike - Status: fix being tested
- Returning to craft from VAB causes craft to go underground (possibly related to Kerbals and landed vehicles dropping through terrain while being approached) - Status: possible fix being tested
- Decoupling events result in various issues including loss of control, incorrect controllability of decoupled subassemblies, loss of camera focus, and other issues - Status: may have many causes, but some fixes in progress
- Save files get bigger over time (TravelLog experiencing "landed" status spam) - Status: fix being tested
- Opening part manager causes major frame lag - Status: experiments ongoing
- Major post-liftoff frame rate lag immediately above launchpad (associated with engine exhaust lighting) - Status: fix being tested
- Root parts placed below decouplers cause issues with stage separation - Status: under investigation
- Vehicle joints unusually wobbly, some part connections unusually weak - Status: under investigation
We have three engineers looking at this and we have already ferreted out a couple of issues - the introduction of axial tilt to KSP2 introduced some discrepancies, and our SOI transit handoff math had some inconsistencies as well. A few other issues surfaced in the simulation code, and we're assessing both the impact of those issues and the scope of work required to correct them.
Issue 3: Certain inline parts cause aerodynamic drag numbers to spike
This bug is the one that saw the most movement this week. Our investigation of the spiking drag numbers revealed that we had a problem with drag occlusion. There is special code that reduces the frontal drag impact of a part that is blocked by another part, and in some cases we were seeing inline parts behave as though they weren't shielded from airflow at all. In some cases, we were also seeing the opposite - wide parts that should have been creating drag were not having their frontal drag assessed at all. Of course, this latter case would rarely register as a problem, whereas the initial problem manifested in all sorts of unpleasant ways - essentially, parts positioned aft of other problem parts behaved like airbrakes, affecting both the overall drag and stability of the vehicle. Even weirder, these drag occlusion issues only arose when a vehicle was built horizontally!
This problem has been corrected. In fact, it’s been SO corrected that after we fixed it, we started to get messages from QA that aircraft felt too fast! We checked the numbers, and they’re correct. We’re still testing this fix, but it’s looking very good for the upcoming update. The details of how this problem was analyzed and corrected would make a very interesting dev diary from Chris Adderley, if he ever gets a few moments to spare.
Issue 8: Major post-liftoff frame rate lag immediately above launchpad (associated with engine exhaust lighting)
Quick clarification: engines had previously each spawned a point light that cast shadows. While this was very pretty, it wasn’t great for performance (and this impact was increasingly pronounced at high engine counts). We have turned off shadow casting for those lights and are seeing an improvement in framerate near the launchpad.
[h3]Bug Reporting Progress[/h3]
I also mentioned last week that we were exploring ways of communicating our current priorities more clearly, as well as giving members of the community more agency to communicate their own experiences and priorities to us. With that in mind, Dakota Callahan and the Community Team have begun to make some changes to the Suggestions and Development subforum on the KSP2 Forums. We’ll get into more detail about our specific implementation next week, but Dakota has already shown some of his work in that subforum - he’s taking several steps, including creating a new Bug Hunter member role, reformatting threads so that they can be up-/down-voted (this is just for bug threads), adding recommended tags/prefixes, and setting up a system that allows administrators to combine duplicate issues. This will start as a pilot program, and its success will hinge on how useful the community finds it and how maintainable our team finds it. The best possible outcome would be that players use the subforum to surface the issues they find most pressing, and our devs have the ability to ask directly for additional context. Again, I’ll provide more detail about this new structure when it’s fully in place, but in the meantime check out Dakota’s post - he’s got some great ideas!
[h3]Engines[/h3]
After posting footage of the three new deep space methalox engines that will be arriving in update v.0.1.3.0, we’ve been asked by a few people what those engines can really do. Our Lead Producer Nestor Gomez (of KSP1 fame) suggested that we share some stats in the time-honored old-school way - with cool blueprint-style graphics! Without further ado, here are the three new engines (with special thanks to Matt Poppe, who continues to do amazing work on everything he touches):
I have run a few missions with these engines, and I can attest that they’ve opened up quite a few new capabilities - ones that will become invaluable when the R + D progression enters the picture and nuclear thermal engines are not yet in reach.
[h3]Community Highlights[/h3]
Last week, we did a space station challenge! Several of your impressive submissions can be seen over on our recent Community Highlights post. Some of this stuff is just nuts.
[h3]Weekly Challenge[/h3]
This week’s challenge is technically about landing, though given Gilly’s low gravity, it might just as easily be called a docking challenge. We challenge you to land on Gilly!
Good luck to you all and see you next week!