X-Plane 12.06 Is Full of Many Things

The content was translated from English to Chinese with the assistance of ChatGPT.

I tested it after the upgrade. I am very satisfied with the new clouds; they display more realistically and perform well, with no drop in frame rate.

Clouds and Weather Since the release of X-Plane 12.0, we have been working on improving the performance, accuracy, and quality of the cloud and weather systems. Version 12.06 implements the first two stages of this multi-step process:

The cloud shaders are now faster and have reduced artifacts. Daniel rewrote the cloud progression method, fixing the zebra striping issue and generally making the scene less pixelated and ugly. The cloud shaders also include a dedicated path for Cirrus clouds, which should look better than the Cirrostratus clouds we had in version 12.0 (“very thin high-altitude layered clouds”). Alex and I rebuilt the noise functions that construct every weather type to get better-looking clouds of all kinds.

While this includes some real-world weather fixes, we haven’t fully updated real-world weather; my thinking is that without proper rendering, we won’t be able to tell if real-world weather has actually improved.

Upcoming features: In Beta 2, “Minecraft-style clouds” (e.g., blocky cumulus clouds, especially in real weather) will be fixed, so enjoy them while they last. Heavy prismatic Cirrus clouds will also be fixed, and we will optimize presets and METAR parsing.

Future outlook: We plan to add a 2D “cloud shell” behind the 3D clouds to handle orbit views and make the Earth look less strange; and we will be doing a thorough check and optimization of real-world weather.

Lighting X-Plane 12.06 fixes some sky color constants, but is not a lighting update. We have a series of lighting fixes internally, but the plan is to implement them carefully and all at once—for example, doing a single lighting update once all changes are complete.

Improving dark cockpits is high on our to-do list, but we also don’t want to adjust cockpit lighting levels again and again, as this would affect third-party developers.

I expect that when we recalibrate cockpit lighting, some aircraft may need minor updates, but third-party developers who have taken it upon themselves to “fix” cockpit brightness (by adding extra lights or tampering with materials) may need to revert their changes. I will try to provide clear guidance and early builds when we reach that point, but lighting is still “in development.”

Rendering and VRAM The biggest change in X-Plane 12.06 isn’t something you can see: we converted the main rendering pipeline from 12.0 (hand-coded) to a render node graph.

Render graphs are very popular nowadays; if you are interested, you can look at things like AMD’s render pipeline shaders. But here is why this change was made: Render graphs allow us to reserve a portion of VRAM while rendering the main frame. X-Plane 12’s rendering pipeline is much more complex than X-Plane 11’s, leading to increased VRAM usage.

In 12.06, we treat VRAM more like an Airbnb (short-term rental) than a second home—at different times in the frame, different parts of the rendering pipeline use the same chunks of VRAM, meaning we need less total VRAM for effects. This change was impossible in X-Plane 11—you cannot alias VRAM reservations in OpenGL.

However, manually coding allocation aliases is tedious—render node graphs automate most of this process and prevent errors.

Upcoming features: In Beta 2, we have a performance optimization that should help CPU-bound users.

Future outlook: In the future, the render node graph will also allow us to use different CPU cores to render different parts of the frame, improving CPU utilization and giving higher frame rates to CPU-limited users. We have a lot of work to do here, but the render node graph makes this possible again.

ATC and AI Aircraft Version 12.06 has many ATC improvements—Jim’s work over several months is released in Beta 1. I will try to get Jim to write a blog post about the details.

A major improvement to ATC: Austin fixed many issues with AI pilots. This impacts ATC because AI aircraft fly more reliably and are less likely to crash, which causes airport operations to stall. We expect stability to improve, as numerical instability caused by AI aircraft crashes would sometimes bring down the entire simulator.

Future outlook: Jim will continue with more ATC fixes and work on SID/STAR support.

What’s Next in the Development Process X-Plane development follows a process; as I type this…

Version 12.05 has been released. Version 12.06b1 is in public testing. Version 12.06b2 is in internal testing, preparing for public testing. Version 12.06b3 is in development—about half of the Beta 3 issues have been resolved, and we are working through the rest. Development on version 12.07 is almost complete—currently a mix of development and testing. We are starting work on features for 12.08 and beyond.

Third-party developers: I believe all known third-party compatibility issues are planned to be fixed in Beta 3, with most already fixed. However, these fixes didn’t make it into Beta 2 in time, which was a few days ago. We hope to release Beta 3 early next week.

We try not to hold up a beta release for fixes that are almost ready—if we did that, the beta would never be released, because there is always one more fix that’s almost ready.

Future outlook: Pawel has been heavily improving the network stack, and his first batch of changes will be released in version 12.07, mainly for professional users. We have more graphics improvements coming soon, and some of Austin’s flight model improvements are being tested.

Finally, here are a few of my own test screenshots for reference only.