Scenery Tech North American Landclass For FSX

By Andrew Herd (9 July 2007)

cenery Technologies, also called SceneryTech, or ST, just to confuse us all, are new to me, but a check on their site explained why, because the company was founded early this year to produce 'innovative enhancements and solutions for the world of Microsoft Flight Simulator, focusing specifically on the scenery aspects of the sim'. Having seen their North American Landclass product, I expect to see more of them. (Indeed, as this was being written, they have released their Europe Landclass For FSX.)

So what is landclass, then?

Landclass, is short for 'land classification' and it describes the system which is used to control the layout of the generic scenery texture tiles which are displayed by Flight Simulator. Even in a default installation of the sim, the landscape you fly over isn't covered with random arrangements of tiles - the textures you see conform (broadly) to the sort of scenery you would be flying over were the real world beneath you. Each terrain tile is approximately a kilometer on a side and just about any type of terrain can be displayed, from the driest desert to tropical jungle using a sophisticated set of texture tiles which are continent specific.

The problem with the default landclassing, which is what you see when you install Flight Simulator out of the box, is that it is very approximate. OK, it is very, very approximate - so approximate, in fact, that it is useless for visual navigation, because many towns and villages are completely missed out and even major conurbations can be hard to recognize, because their shapes aren't correct in the sim. Scenery Tech's landclass improves on the default scenery by using extra data sources and processing techniques that go well beyond Microsoft's processing of the default landclass, the result being scenery that more closely matches the terrain you would see during a real flight, but uses the default terrain tiles to do so and makes no significant impact on frame rates. The good news is that because of the way landclassing works, you can install any replacement ground texture set you like and the landclassing will organize it without further user intervention.

What landclassing does not do is to affect other scenery elements besides terrain textures - this means that water bodies, roads, and railroads, which are based on vector data in FSX, will still look exactly the way they did before the North American Landclass product is installed.

Another point which is worth appreciating about landclassing products is that although they make the FS landscape they describe look more realistic, the result isn't photorealistic. For that you need to install a photoscenery package, the pros of which are that the ground below you will look photoreal; the downside being that such packages only cover limited areas and consume vast amounts of hard disk space. Despite the improvements in the way FSX displays photoreal terrain tiles, if you want to improve the look of the FS scenery over large areas, the best compromise is to buy a landclass package; the great strengths of landclassing being that the 'edge blends' are much less obvious than they are with photoreal scenery and that (assuming you like the FS seasons) seasonal variation is preserved.

I tested version 1.1, system requirements for which are any system which can run FSX and Windows XP SP2 or Windows Vista. I did the testing on a 3.2 Ghz Pentium D with 4 Gb of RAM and a 512 Mb ATI Radeon X1950XTX.

The package is a very small download and installation takes virtually no time, the only user intervention being to confirm that the package should backup the default textures. After that, FSX loads the new landclass data instead of the default information supplied by Microsoft. Coverage extends to the entire continent of North America, which means that you get Canada and Mexico thrown in.

The first thing to note about this product is that it only works in FSX, because of incompatibilities in the way older versions of Flight Simulator display terrain tiles and that the 1 km square terrain texture tile format imposes a limit to how good a landclassing product can be - any detail with dimensions of less than a kilometer a side cannot be shown, no matter how accurate the data behind the package.

The manual doesn't give any clue as to which data sources Scenery Tech used to process their data, but in addition to basic land classification maps, they state that they also used climatology, political, elevation and population maps to generate the final product. Given the enormous area involved, the process was largely automated, but the developers did sample cross-checks with photographs and satellite imagery for quality control purposes. Given that they couldn't possibly have looked at every square kilometer of land in North America, that means that your mileage may vary.

Among their goals was to eliminate the large masses of 'monoculture texture' that Flight Simulator is prone to create due to the coarse grain of the default landclass data; to improve on the outlines and urban/suburban transitions in towns and cities, not to mention reprieving thousands of smaller towns and cities that the default landclass didn't deign to display; and to create smoother transitions between plains and steep slopes, which have always looked unnatural in Flight Simulator. In the version I tested, the developers have addressed a few problems noted by early adopters and beta testers, including the lack of permanent snow on higher mountains, 'greening' in Alaska and various installation bugettes in Vista.

I did the testing on a 3.2 Ghz Pentium D, with 4 Gb of RAM and a 512 Mb ATI Radeon X1950XTX, using Windows XP SP2 and FSX SP1. For the purposes of the review, I used the FS2004 Ford Trimotor, imported into FSX using FS9toFSX and selected three areas at random. These were, in order, from the top row of screenshots to the bottom, a flight from Albuquerque, New Mexico; a flight from Heigle Field, Mayersville, Mississippi; and a flight from Eastern Oregon Regional. Actually, I confess that these weren't entirely random, as I did reject a couple of choices because accepting them would have involved presenting screenshots showing the same kind of landscape, but the locations I used were picked as randomly as I could, to avoid the lure of choosing the obvious places that show this kind of product off to best advantage. What I wanted to do was to capture screenshots that showed the North American Landclass as most users will experience it.

As you can see from the shots, North American Landclass (NAL) clearly does make a difference, although at first glance it isn't that obvious. I spent a lot of time comparing screenshots with sectionals and came to the conclusion that the result is usually an improvement on the FSX default landclass, but the amount of improvement is variable and in any event, the effect is quite subtle. The Albuquerque shots are a good example of this - take a look at the terrain surrounding the airport in the left and right hand shots. In the right hand shot (NAL installed), the town doesn't crowd right up to the runway the way the default scenery would have it and, as far as the larger airports are concerned, NAL usually has the effect of creating more clear space around the runways, which is more realistic than the way FSX would have it. I have had to dodge churches stuck right at the threshold before now. However, as I noted above, the size of the terrain tiles imposes a natural limit on how accurate the outlines of towns can be.

Now examine the Mayersville pictures - once again, the default FSX landscape is on the left and the NAL landclass is shown on the right. Once again, at first sight, installing NAL doesn't change much, but if you look carefully, the outline of the wooded areas has changed out of recognition. The Oregon Regional set are the most striking, in that NAL (shot on the right again) has done exactly what the developers have said it should and has banished the texture monoculture that the default FSX installation displays in the area in the upper right of the left hand shot. The wooded areas have shrunk considerably and the town looks much more like a farming community than it does in FSX.

The question many simmers will have on the tip of their tongues is: 'Can you do proper VFR nav in FSX with North American Landclass installed?' The answer is that you can, in some places, and VFR nav is definitely easier than it is in a default FSX installation, but the lack of visual features present in a real landscape and the 1 km square grain imposes a fundamental limitation on what can be done. With the product installed, most areas of the North American continent looks more realistic in FSX and there is much less terrain monoculture, so Scenery Tech have definitely achieved what they set out to do.