Here are the results of the latest usage data as of 05 October, 2017. If you’d like to compare, here is the last usage data result from February 2017.
It took me a bit longer than I would have liked to compile the graphs while working around the 11.10 beta, but we now have a handful of easy-to-digest charts, plus the raw data at the bottom of the post for those that are interested. Read More
X-Plane 11.10 beta 5 is here, and a before and after says it all.
Tyler heard your pain (as did the rest of us, as we received approximately 8,414,493 requests to kill the FPS nag) and we have changed the low frame-rate warning from the perpetual flashing “you’re too slow” shown on the left to the pop-up warning on the right. And if you like flying a slide show, you can click “don’t show this again” and … we won’t!
The new warning is a bit more conservative – you should only see it if you’ve got persistently low framerate – a transient dip due to texture paging should not make it pop up. If you see it appearing spuriously, please file a bug. In these pics I’ve set my poor 3-year-old iMac to maxed out AG, maxed out shadows and maxed out shaders all at once with the 747 to dip below 20 fps.
The rest of this post discusses the “why” behind this dialog box.
X-Plane has some fundamental rules about how it simulates flight – these are our design parameters.
If you consider all of these things, you can see the problem. You can crank up your settings on an old machine and the rendering engine needs more than 50 ms but the physics engine won’t simulate more than 50 ms in a single step.
X-plane does the only remaining option: if your computer cannot sustain 20 fps rendering, your flight will be simulated slower than real time. For example, at 10 fps, a flight from Boston to JFK will take 90 minutes, not 45.
It turns out that lots of X-Plane users don’t know about this behavior, and as a result, Austin receives a steady stream of emails complaining that the sim is unrealistic because en-route times are too long – virtually all of them are caused by low fps.
So for 11.10, Austin did what Austin does: he put a big loud message on screen to tell users that they were below real-time simulation.
The result of this message was not users going “oh, I’ve learned something, I’ll turn down my rendering settings.” It was a huge number of bug reports that X-Plane 11.10 had catastrophically worse FPS than X-Plane 11.05. In many of these cases, users thought they were getting 20 fps because the flight model reads 20 fps in the time window data output (a very confusing display) and there is no bitch-o-gram.
I considered the option of just nuking the message a second time, but there may be problems with running at low fps that users don’t realize. For example, if you’re on VATSIM doing 170 knots on final like the controller asked at 10 fps, you’re doing…85 knots and your 737 is looking a lot like a C172.
So we went with Tyler’s popup + never-show-again design; it brings the issue of low fps to the surface, but lets users dismiss it forever if they can live with non-real-time simulation.
When discussing this with users I did get asked a lot, “why don’t you run the physics and graphics independently so we can run in real-time at < 20 fps”. There are a few reasons why we did not (and are not) considering this approach.
So we’re going to keep focusing on performance optimization that will benefit everyone and not take a side-tangent into making 15 fps flight run in real-time.
* If the time between frames is too large, self-damping forces on the aircraft and feedback-based control systems will not react properly because they will not respond quickly enough, due to there being no simulated frame shortly after a large force is introduced. The result can be incorrect handling at the outside of the flight envelope, for example.
TL;DR: Running X-Plane with sudo is a bad idea. Instead, create proper udev rules (per this and this).
During the 11.10 beta, I’ve gotten a lot of bug reports from Linux users who report that their keyboard is being recognized as a joystick. This is… sort of a bug, but mostly intentional.
(If you’re not a Linux user, this won’t apply to you… but it will bore you! 😉 )
On Linux, prior to X-Plane 11.10, we were very picky about what USB devices we considered to be a joystick: we required a device to present a so-called “absolute” axis (in contrast to a “relative” axis like a mouse uses). The downside of this is that it prevented home cockpit builders from creating button-only hardware.
So, in 11.10 and beyond, we relaxed the requirements: if a USB device presents us with either an axis, button, or hat switch, we’ll treat it like a joystick.
The problem with this policy seems obvious: keyboards have “buttons”! Like, 104+ of them!
The reason we didn’t worry about this is that the keyboard is only accessible (as a USB device) to programs running as root. So long as X-Plane runs as a normal user, it doesn’t even have the option of treating the keyboard as a joystick.
The impetus for running as root (via sudo) is simple: if your Linux distro doesn’t recognize your joystick hardware as something that should be available to normal applications, running as root is a brute-force way to let X-Plane use your joystick.
Let me say emphatically: This is a bad idea.
Especially with early, buggy betas, running as root makes it possible for X-Plane to do way more damage to your system than would ever be possible as a normal user. Consider the unlikely—but possible!—scenario where somebody made a typo in the code which inadvertently tries to delete a system folder. There are two possible outcomes here:
Running X-Plane as root is like giving a blank check to every cashier you buy something from—it’s way more power than they need to do their job, and it’s liable to burn you at some point!
As described in the latter half of this old dev blog post, you don’t have to run with sudo. Instead, you can create udev rules to tell your operating system to let normal applications use your joystick. The GUI tool linked at the end of that post makes it even easier.
(Some users found the instructions there confusing; this post on the Org might help.)
Remember that after you create your rules, you can even submit them to your distro to make life easier for other flight simmers!
There’s one hitch: after running with root, your file permissions (especially your prefs) may have gotten screwed up. This can be fixed from the terminal by making your normal user account the owner of your X-Plane directory, like this:
$ sudo chown -R <username>:<username> /path/to/X-Plane/
(So, in my case, my username is tyler, and X-Plane is installed to ~/Documents/X-Plane/, so I’d run $ sudo chown -R tyler:tyler ~/Documents/X-Plane/.)
Now, to those of you who have been running as root… “go, and sin no more”! 😉
X-Plane 11.10b4 is out. The release notes have complete bug fixes (we try to list everything; Jennifer works off the bug base and the GIT commit log), but two big fixes:
Widget-based plugins now do not scale. The widget drawing code path, as it turns out, is totally not ready for UI scaling or multi-monitor.
If you found any problems using plugins (mouse clicks not working, double drawing, things disappearing) and you still see them in beta 4, please re-report a new bug based on whatever you now see!
Plugin authors: our intent is to not scale widget-based plugins – the widget drawing path is full of assumptions about the drawing environment, and the code is split between plugins, public libraries, and the DLLs in X-Plane itself.
Our long term intention is not to upgrade XPWidgets, but rather to offer some kind of modern replacement that leverages our UI, is easier to use, and is compatible with all of the modern facilities in X-Plane.
Unfortunately that doesn’t leave widget-based plugins with a lot of good options in the short term. As a plugin author you’ll need to look at the scope of your UI and decide whether you’d rather recode it in straight XPLMDisplay APIs or wait until an XPWidgets replacement is available.
As we move forward with the beta, we’ll write up some posts on X-Plane 11.10’s the new features – there are a lot of them, to the point where I’ve lost track of what’s actually in the release. Right now we’re in the “does it work” phase, trying to get a beta that works for everyone without crashing. (Beta 1 worked fine for everyone in the company, but often our internal machines are very similar to each other, so early betas catch things we missed.)
So what follows is a big pile of nerdy stuff…I’m going to add random images in to make the post less boring. So picture is not related.
Where Do The Bugs Go
When you file a bug with our bug report form, it goes to a shared email in-box that someone triages – usually it’s Jennifer, but sometimes it’s me or Philipp. The person triaging the bug will then forward it to our internal bug tracking system (that’s where those XPD-123 numbers come from) or possibly forward it to tech support – we do get a lot of “my sim is broken, help!” in the bug reporter.
This is why I always jump up and down and go “file a bug!”: everything in the bug reporter gets looked at, and everything that is then filed is permanently tracked. At the end of 11.10 we can check the bug list and see what hasn’t been fixed. Like all software, not all bugs will be fixed by the end of 11.10, but if the bug is tracked, this avoids us losing the bug.
Here are some ways to report a bug that are not tracked and are extremely likely to get lost:
The problem with direct email is that it doesn’t go through the tracking system, you might not get the right engineer, and again, you’re bypassing the mechanisms we have in place to not lose things. If you email someone organized and responsible like Tyler, he might file the bug for you. If you email someone like me, whose in-box looks like a grenade went off, there’s a very good chance I lose your report.
Jennifer tries really hard to list every item that is fixed in each beta, so that you can tell when your issue is fixed and it’s worth re-testing/re-reporting.
This system is far from perfect, and the number one request we get which is reasonable is better linkage between the internal tracking and the user reporting. I sympathize because we have the same problem of “it’s a black box” with the technology vendors we depend on (Apple, Microsoft, Intel, AMD, NVidia).
Changing How We Build
With X-Plane 11.10 we moved to cmake for our build system. Previously we would maintain separate project files for all three operating systems. That’s about 3x the amount of work it should be, so for 11.10, Sidney and Jörg moved us to cmake, which lets us manage X-Plane as a project once.
The down-side is that there have been a number of serious one-time bugs due to projection configuration problems, since using cmake meant rewriting all of the configuration info for building X-Plane. This is what caused the Linux bug in beta 1 that we required libc++ (fixed during 11.00’s beta process, it popped back up when we replaced makefiles) as well as a number of other random bugs we fixed before public beta started.
In the long term cmake is a win – having gone through the pain of the migration, it’s just quicker for us to administer X-Plane’s project files, which means more coding and less fighting with X-Code, MSVC, etc.
More Robots
In the last few months we’ve automated our build and our packaging process, as well as the amount of testing done automatically by the build system. Hopefully this will turn into bugs being caught earlier, and it makes it easier to cut new betas – getting quick betas out to fix crash bugs wasn’t time consuming. I expect the beta count to be higher for 11.10 than in the past due to the lower cost of recutting the build.
(If I had to cut five betas in a week for 11.05 I’d be pretty cranky at everyone – five betas in a week is totally doable now.)
Graphics Cards That Remember
Before X-Plane 11.10, X-Plane would set up shading for a given material by telling the graphics card about every aspect of the material. Over and over. Every time the material was used. For every single frame. For every single view in the frame.
X-Plane 11.10 now stores parts of the materials in VRAM, so they can be referred to as needed. This is part of our restructuring of the rendering engine for VR, Metal and Vulkan.
This was also the cause of the “invalid UBO” errors in beta 1 – now that we are saving materials and not just reiterating them per frame, we have to get the book keeping right. Sidney set the sim up to crash if the book keeping is done wrong. (This is a good thing – the sim is going to crash anyways if the book keeping is wrong — at least this way the auto-report explains exactly what happened, rather than us having to autopsy the resulting carnage and squint to find the root cause.)
AMD Users: this code is not working on AMD cards right now, which means you aren’t seeing some performance improvements. We’re working this week to see if we can get this going on AMD cards too – stay tuned.
I just cut a quick new beta build of X-Plane 10.11 – Jörg fixed the Linux crash. The crash was a problem with the plugin .so’s and we don’t even know how the bug happened, but it’s fixed now.
Linux users: since the crash is at startup, you won’t be prompted to auto update (because X-Plane crashes before the auto-update check can run). So to fix your beta installation, re-run our installer and pick “update x-plane” with the beta box checked. You’ll get beta 3 and be back in business.
We’ll fix more bugs next week, and the rate of betas may slow down, but we’ll try to patch crashes as quick as we can.
If you have 11.10 beta 1, you’ll be auto-notified to update. (If you’re locked out, e.g. for users on Linux who didn’t have libc++, use the installer and check “Get Betas”). See the release notes for bugs fixed in this beta.
Thanks to everyone who reported bugs! If your bug is not yet fixed, don’t panic – we cut b2 quick to fix the pile of “OGL_ubo_is_valid(s_environment_ubo)” crashes. If you have one of these in b2 please re-report it (and auto-report it!)
To get it, make sure you have an X-Plane install you can scrap, have a stiff drink, and check “get betas” in the installer.
Release notes are here. I’ll try to post more over the weekend about some of the new stuff, but there’s a lot, and we’ve probably left things off the initial notes. For now, since it’s beta 1, our main concern is “does it work at all?”
We’ve been working on bug fixes like crazy, and over the last week or two we’ve run a small internal beta of 11.10 to try to get the biggest, nastiest bugs out. So far it looks like we’re on schedule to put out a public 11.10 this week.
Besides fixing bugs, there are still a few irons in the fire for 11.10 that might go into the beta after public beta 1:
A bunch of stuff for developers and artists is already done and ‘in the can’ for beta 1:
In preparation for this beta, Jennifer ran off to Las Vegas. We might reasonably disagree on how to interpret that.
X-Plane 11.10 is the first major version release with a lot of code changes and new features. By design, this version has a lot of big changes in it that we’ve held back for weeks or even months. This also means it is more likely to be unstable and buggy, especially for the first few beta releases.
We’ve recently progressed to internal beta testing. Now we should have a public beta sooner rather than later, so I wanted to bring back out some great tips on beta testing that Chris wrote way back in 2012. Nearly all of the info remains as relevant today as it did 5 years ago, and I’ve included his best practice tips below. Read More