Last weekend, we wrote a summary of Laminar Research's presentation at Flight Sim Show 2019, with mentions of landmarks going into X-Plane 11.50, performance with Vulkan, and X-Plane Mobile.

Earlier today, Ben Supnik of Laminar Research posted about X-Plane 11.40 beta 8 and a roadmap update on their blog.

The alterations and additions in X-Plane 11.40 are almost all flight model changes, and Ben noted that a major update in this format is a new experience for them. "In the past, when we’ve updated the physics or systems, it would be in a giant “omnibus” release, where everybody’s latest code went out at once (e.g. X-Plane 11.10)," Ben said. He then described how these updates take forever to debug, with so many things being changed.

However, Ben has found the approach to 11.40 positive: "So far, at risk of jinxing the beta, it appears that the physics-only approach is working a lot better. It has been quicker to find bugs when they are reported, and the overall level of crazy is a lot lower than in past releases."

After outlining a bug where the flight model attempts to divide by 0 and causing crash to desktops, Ben wrote that they may have a beta 9 and 10, and possibly another week with two further betas following that.

A section dedicated to experimental physics came next, which told of how applying fixes to the experimental flight model differed from other features. This is because it usually takes much longer for developers to adjust the flight model of their aircraft, and hence the invention of the experimental flight model.

Flight model changes in 11.40 that affect how an aircraft flies, such as delayed wash propagation from the propeller to the tail, require the experimental flight model to be enabled, whereas "simulations that change how the aircraft flies in unusual circumstances that you can’t tune your aircraft to," such as stalling and wake turbulence, is always on.

Furthermore, Ben explicitly stated that developers of third-party aircraft need to test their aircraft using both experimental and non-experimental flight models in 11.40 as soon as possible, and if the non-experimental flight model is moderately different, they should file a bug.

The next section is dedicated to Vulkan, and Ben confirmed it will be introduced in version 11.50. Add-on compatibility, as has been mentioned many times already, was reiterated:

• "Add-ons doing supported things, like 2-d panel drawing and UI should just work in Vulkan and Metal – we’ll take bug reports to fix compatibility issues.
• "Add-ons doing unsupported things won’t work in Vulkan and Metal at all. Your 3-d drawing callback won’t be called, or your attempt to grab internal GL resources will just fail (because none of our resources are GL).
• "X-Plane running under OpenGL should “just work” for pretty much every add-on, including ones doing sketchy things, and should be faster than 11.40 but not as fast as Vulkan or Metal."

Ben stated: "I expect the Vulkan beta to be a relatively long one," and went on to say they are still looking to begin the beta this year. With enhanced insight into the Vulkan rendering engine and driver, "the work that happens inside the driver is much more predictable, bounded, and can be viewed via modern profiling tools."

Finally, Laminar Research is planning to make large changes to light, the atmosphere, colour, and with "organising our frame," but only once Vulkan is done and dusted.

If you wish to read the blog post in full, you may do so here. Don't forget to check out their presentation at Flight Sim Show 2019.