When I tore my shoulder playing frisbee and went to the Doctor, he took an X-Ray. Why? Well, that’s obvious: my skin makes it hard for him to directly inspect what was wrong inside my shoulder; the X-Ray shows right through the skin – in that case, it revealed a torn ligament.
It’s the same way with X-Plane. If I want to see what’s really going on in the sim, using real test cases makes life hard. Our artists try hard to hide the underlying mechanism of the sim and instead create a seamless plausible experience. In a good scenery pack you can’t see where one object ends and another begins, or what is a beach and what is an orthophoto.
So my life as a developer is a lot like a radiologist – I spend a lot of time looking at the inside of the sim, and I do this by using test art assets. A good test case is easy to build and clearly identifies the underlying mechanism in the sim. What follows are a few examples of the kinds of test cases we use.
This was one of the original global lighting tests. I needed to see if the lights performed on a large scenery, so I used George Grimshaw’s KBOS, and installed two custom lights. The lights are intentionally primary colors (green and red) so make the blending and mixing completely clear.
This is a test airplane panel to look at the 
effect of odd-sized instruments and resized panels on pixel clarity. The test case goes through every alignment possibility using art-work that has 1-pixel lines to show blurring.
This is a test pack of roads – the pack contains one of every kind of road. The sim is put into a debug mode that labels the road with its code. Using this, we can quickly inspect the entire road art asset pack to see if any road types are buggy. This is a very early version of the roads – one of the original mockups. (That’s why a lot of the roads are missing whole sections.)
Here’s another road test – in this case, there is a custom scenery pack that replaces the cars with colored axes, making it easy to debug the alignment of the cars relative to hills and highways.
These two are test autogen packs; the markings allow me to debug the code that places autogen elements in the sim. The real autogen elements blend together, making it impossible to spot bugs; these ones show alignment errors clearly.
This is an older shot from the weather system with the shadowing vectors on – the lines all over the clouds show the measurement of light going into each part of the cloud. Since clouds can be soft and nebulous, the lines show clearly what would otherwise be hard to visualize.
This test object was built by propsman and exercises approximately 100 different features of the version 10 pixel shaders. In this case, each shader ‘trick’ has a piece of artwork with a clear label to show which part of the shader is where. The real art assets use the shaders in subtle ways that make them hard to debug, but in this case, if the albedo is missing (for example), it’s really obvious.
This is a piece of DSF with the beaches replaced with a beach calibration texture. The beaches are solid and have numeric markings to show which part of the texture is being applied at any given time.
Why show these? My point is this: I spend most of my day looking at the sim with test artwork to see what’s really going on. Many of the art assets I work with are specifically built to test – others have been hacked to find bugs. When I take a screenshot, it is usually to illustrate a particular point about the sim; the rest of the picture probably contains random junk that built up on my hard drive.
So: the marketing people will get you nice pretty screenshots that you can get excited about, but for the time being, most of the pictures here are designed to illustrate only one specific point, and are not at all meant to illustrate what the final X-Plane 10 will look like. You’re welcome to speculate all you want on the rest of the picture, but you’ll be using an X-Ray to look for a skin rash.
That’s the kind of posts that I like! 😀 (not that I don’t like the others)
I agree these kind of posts are very informative, thanks!
I thought you were revealing that X-Plane 10 has a Magnetic Anomaly Detector in one of the stock aircraft, a P-3 Orion perhaps. Now that I think of it, I could make one… are the first-gen MAD manuals declassified yet?
What am I thinking. I’d have to create a MAD for Guy Montagu-Pollock’s Comet, to help him extend his model to a Nimrod.
Very cool indeed, thanks for sharing! The shot of the clouds was awesome! Looks really good!
Thanks for taking the time to “Show & Tell” Ben, it is so Cool to Really See what the sim is all about. I have a new found respect for you people.
To me it seems that most of the criticism is spent on the “final” product without ever knowing what the product is about or how it “works”. This has been a very informative post, and I wish everyone in the “community” would check this out.
Your time is appreciated, and the “product” will show these efforts!
Great post – shows the professionalism and talent of the people working for Laminar as well as the complexities of an almost impossible task. Love those clouds and water. Do I get a cookie for that now?
It would be interesting to see how Rendering Options deal with auto-gen buildings and roads.
Regarding bitmap alignment issues, does .eps artwork have any merit or future in this sim?