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jordanal

Mesh Issues - resolve??

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Maybe someone here will know...I have FS Genesis mesh for the entire North American Continent, and was wondering if there will ever be a fix to take away the raised aiports. I have to be honest, I have disabled it for my home area because my home aiport was on a plateau, and I just could not stand it on final, looked goofy. I know it is all about the "round earth" and not having sloped runways, but I was also wondering what you guys are doing. Are you still using it and ignoring it? Or have you tried something to fix it? Thanks for help.Danon -

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I use it and ignore it. Its a small price to pay for all the rest you get and hopefully Justin will find a way to fix it eventually.

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Justin has said he is looking into fixing it with some sort of blending/ smoothing technique. I take that to mean it may or may not happen. Do you realize the amount of work that might take?It's not a problem of the mesh. It is the inaccuracy of the airport elevation datasets. Many of those airport elevations are reported by the airport managers themselves, and are NOT scientific/accurate.RhettAMD 3700+ (@2585 mhz), eVGA 7800GT 256 (Guru3D 93.71), ASUS A8N-E, PC Power 510 SLI, 2gb Corsair XMS 3-3-3-8 (1T), WD 150 gig 10000rpm Raptor, WD 250gig 7200rpm SATA2, Seagate 120gb 5400 rpm external HD, CoolerMaster Praetorian

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There are two fixes:Go to a less detailed mesh - which you have done. That smooths the transitions much more easily.The other is to learn one of the small area mesh programs and make adjustments to the area around the airport polygon to suit your desires. Nothing nation/ world wide will every beat local knowledge when it comes to mesh.While a great many airports are errors - the relatively flat airport of FS is the big issue.Take a look at this airport diagram for KLAS - Las Vegashttp://204.108.4.16/d-tpp/0712/00662AD.PDFNote the following elevation points (all feet)Rwy 25R - 2033Rwy 25L - 2048Rwy 7L - 2179Rwy 7R - 2157Rwy 19L - 2078Rwy 19R - 2089Rwy 1 R - 2176Rwy 1 L - 2181You will also note that the Official airport elevation is 2181 - the highest runway point on the airport.Now we look at the airport in FSX - using Airport Design EditorRwy 25R - 2181Rwy 25L - 2181Rwy 7L - 2181Rwy 7R - 2181Rwy 19L - 2181Rwy 19R - 2181Rwy 1 R - 2181Rwy 1 L - 2181Official Elevation - 2181You can see the threshold of Rwy 25R is 148 feet higher than the real world.If you look at a map program - you will see S Eastern Ave just east of the Rwy 25 threshold.With less detailed default mesh that road is about 140 feet too high and it takes about 1/2 a mile to curve down to the real elevation of the mesh.With a highly detailed mesh - that curve occurs in about 100 feet - so it produces a very high wall.The same thing occurs with E Tropicana Ave on the north side of the airport.Now that's what happens at a well documented airport.Across the world - I've be vastly surprised to find if 1/4 or 1/3 of the FSX 24,000+ airports was accurately surveyed as to position, runway lengths, runway heading and elevation.Many of those surveyed were done before GPS systems became common and easily available.Also, many airports are surveyed based on a different world grid than the GPS system uses - with a 100 meter inherent difference in position between the two systems.Then you've got the issue of deliberately miss reported airports. This is an issue with small, private and bush strips where the real location is purposely wrong in the records to discourage pilots from landing at the airports withour permission.Up to a certain size, private airstrip owners can request their airports be left off/ out of VFR charts in the US.Satellite and aerial photo systems like Google Earth, Google Maps, maps.live.com are great at helping us line up those airports with FS world.Because Flight Simulator requires much, much greater accuracy than the real world flying.Flight Simulator expects everything to be accurate down to nine decimal places.In the real world, except for WAAS systems - being within 100M is close enough. Because you don't land an aircraft based on the position of the runway on the chart - but on the position of the runway out the front window.Even a CAT III ILS system with full autoland can be quite far from the charted position and work perfectly - because the important thing for such a system is that ILS matches the runway exactly.But such discrepancies in Flight Simulator give us 148 foot high plateaus at runway thresholds, AI aircraft landing in the grass, etc.I'm not trying to make light of the issue - it's real - but it's also part of the tradeoff we all make with FS. More autogen trees, fewer FPS, more detailed mesh, plateau airports, and on and on.If you spend enough time flying at one or two airports which really need help - five to 10 hours invested in learing how to manipulate mesh yourself will give you much happiness in the future - because nothing FS is as great as flying over, into, around something you've 'fixed' yourself.

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Hi all,nice summary of the situation, Reggie!Since ACES decided to use much higher resolution terrain data for the FSX mesh files it faced the same issues. They used an automated procedure to smooth the elevations around airport flattens to avoid major elevation "steps". Currently, none of the available terrain mesh add-ons does something similar, which explains the difference to FSX default.While manipulating the terrain data itself is a suitable option it does require sophisticated GIS tools and expert knowledge.On the other hand, one can use a series of segmented sloping "flatten" polygons to achieve a similar effect. Gary Summons posted a couple of screenshots of this type of method here: http://www.uk2000scenery.org.uk/forum/index.php?topic=414.0I've been using a similar approach for my projects for a number of years now. SBuilderX is a great tool for doing these kinds of flattens and, once you know what you're doing, it only takes about 30-60 minutes per airport to fix it up for use with high-res add-on mesh. Obviously, 60 minutes times 24,000+ airports is still a lot of effort but most complaints tend to involve the same regional or international airports. Perhaps once people are getting bored of making new AFCADs they will switch to making flatten adjustments... ;-)Cheers, Holger

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I wish someone would at least correct the airports featured in the default fsx missions.

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Interesting reading as always from Holger and Reggie. I wonder if someday we'll have a flatten tool for these adjustments built right into the AFCAD utility itself? Another item for the to-do list for FS11, ..., FS89, LOL.. ;)

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What I have done is convert the elevation mesh source data to a grayscale. Then in a graphics program I apply a uniform gradient. The problem is that I do it by hand, and while I can specify the behaviour I want, I haven't figured out a way to automate it. The main problem, is that the difference between the airport elevation and the actual elevation I need to match have to be within 256 meters. HEre is an example of KLAS. You can still see the outline of the flatten in places, this will result in cliffs.http://forums.avsim.net/user_files/181577.jpgscott s..

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