Testing and Future-Proofing Your Airplanes

Airplane authors: prepare yourselves!  I am now very close to closing the last of my fixable bugs filed against the 10.10 aircraft SDK.  This means that the next beta will be the one to test your airplanes against.  If there is a problem with your work in 10.10 and you tell us after 10.10 goes final, it may be very hard for us to fix it, so if you’ve been waiting on 10.10 betas, please go get the beta now and be ready to test shortly!  If you have been waiting and letting your users try 10.10, start downloading now!

One of the main goals of 10.10 is to have the airplane authoring SDK provide similar visual results when HDR is on and off; another is to have these results remain the same for the rest of the v10 run.

Long Term Future Proofing

Lighting model changes represent one of the trickiest engine changes we can put into X-Plane.  When done right they add realism, but they also fundamentally change how an author’s work looks.  With 10.10, the v10 lighting model is “done” for the version run, but I don’t think it will be the final model forever.  The v10 lighting model definitely contains some compromises to make translucency and v9-style authoring techniques work.

A question came up in the comments as to whether HDR mode with the deferred rendering engine and global lights might become the standard rendering mode for X-Plane 10.  I think some day it may be – just as we used to have an option: pixel shaders or not, and now they are always on, I expect that most rendering innovations will eventually become standard over a long enough time frame as hardware continues to scale up.

(We have already seen this in first person shooters: the first ones to feature a deferred rendering engine often provided two rendering modes; now new games tend to be deferred-only.)

We certainly view the deferred engine and HDR mode to be preferred, and that’s why so many effects are HDR only.  There are effects we can only do with a deferred renderer, and there are effects that are much cheaper to build into the deferred renderer.

Beyond X-Plane 10

If you are working on an aircraft and you’d like it to work well not only with X-Plane 10, but also X-Plane 11, here are a few things to avoid.  These features are supported in X-Plane 10, but we see them as compatibility features, not “good things to use.”

• Avoid using the cockpit texture without real 3-d lighting.  This happens when you use ATTR_cockpit without GLOBAL_cockpit_lit.  The cockpit texture without 3-d lighting is still supported in version 10 but it is not recommended, and you can get some weird artifacts.  Over time these problems will get worse (as the lighting model becomes more sophisticated) and a 3-d panel that doesn’t obey the lighting model may not even be possible after X-Plane 10.  Fortunately you can use GLOBAL_cockpit_lit to turn on 3-d lighting and in almost all cases it will “just work”.
• Don’t use ATTR_diffuse_rgb and ATTR_emission_rgb.  Instead, paint the color into your albedo and lit textures and use ATTR_light_level.
• Make absolutely sure that everything translucent is marked ‘glass’, and that nothing is translucent unless there is a really good reason.  Alpha is really tricky for a deferred renderer!  This is good advice for v10 as well.

X-Plane 10.10 beta 10 will be out soon, as well as more detailed instructions on airplane updates.

About Ben Supnik

Ben is a software engineer who works on X-Plane; he spends most of his days drinking coffee and swearing at the computer -- sometimes at the same time.

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