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Holger

High res localized mesh

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I downloaded Justin T's Green MTN mesh and it seems to work very, very well in FS2004, altho the install program only permitted installation to FS2000/FS20002 directly, so I moved the .EXE program into the proper spot in FS9. Definitely helps the terrain even in the Burlington area itself....thanks Justin!Now........The KBTV Burlington VT airport approaches have some very steep gradients which are created by the Winooski river which has cut some deep channels quite close to the airport. We are talking very steep rocky cliffs here. Placing photoreal images down on this mesh however revealed a few anomalies.I wonder if it is possible to place a very high resolution mesh just in the immediate areas where I need steep gradients, and I would simply iteratively and manually enter and edit the altitudes until I am satisfied I've got it right. Most of the local area is just fine as is but once you put in a photoreal serpentine river, you don't want to see it climbing a cliff. At least I don't.This is a beginner question, because with learning GMAX, Terrabuilder,a collection of SDK's, coloring in photoreal maps and building my own PC , I have only limited knowledge about mesh, and I shrink from the idea of trying out mesh programs until I find one I feel I can use. I don't mind the grunt work, but I have enough on my plate without learning a complex new software pkg. Comments / suggestions would be appreciated. The steep gradients will require a high res result, tho.PS Justins mesh was made from 38m data.

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Hi John:in cases like these it's often useful for us lurkers to see a screenshot of the area in question; it helps us to better understand the scope and extent of the 'issue'.Anyway, if it is really 'only' a matter of accuracy (and not, say, a systematic displacement of the mesh file or some problematic influence of the airport's flatten switch), I'd suggest to first check for high-res data to superimpose on the FSG mesh. The USGS has 10-m data available for many areas, in seamless rectangular chunks of your own specification: http://seamless.usgs.gov/. If these data are available for Vermont, you should download them in BIL format, as that can be used directly by the FS mesh compilation utilities. The utils are included with the FS2002 Scenery SDK (http://www.microsoft.com/games/flightsimulator/fs2002_downloads_sdk.asp ), which also provides an intro to custom mesh design. Before you download the USGS data, you need to figure out the spatial extent for your desired level of detail (LOD10 or higher). There's no step-by-step tutorial out there but the site that does a great job of explaining the LOD grid considerations for mesh design is Steve Greenwood's: http://www.fs-traveler.com/welcome.shtml. He even has an Excel spreadsheet tool to help you with the calculations.The MS TMFViewer utility is the most efficient tool for checking your mesh before installing in FS (part of the Custom Terrain Textures SDK on the MS site listed above). Hope this will get you started.Cheers, Holger

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Thanks for the head start, Holger......my delay in responding is due to my transit from Vermont to Florida for the winter......

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I rigged up a picture where I hoped to be able to remove a few distracting features at the approach to KBVT Burlington's main runway. Point A has a bulge which seriously distorts the Interstate hiighway which runs by the runway visible at the top. Area B and Area C are a prominent collection of industrial buildings which are all perched on a high cliff over the river which winds past the airport. Area C should be at the same height as area B.Ideally, the interstate should run smoothly down to the river, the river should be flattened, and the area c raised too area B's elevation.I concluded that a serpentine river winding through some very deep cuts in the earth would require a very high localized mesh, and that it might be possible to create the dataset manually rather than download the data. I am thinking about gradients as steep as those around Hoover dam, for example.Additionally, Lake Champlain in FS2004 has an elevation of about 55 feet, which is way off....the lake generally runs 96-99 feet above sea level year round. This is one reason for my wariness regarding a complete high resolution makeover, instead of a localized fix, since the new terrain would have to merge seamlessly by the lake a few miles away.IUf there is no proven way to patch up local anomalies I would prefer to simply use a flattening bgl to smooth things out. Am I off base here or just hopelessly optimistic?

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Hi John.As Holger has discovered, all the terrain scenery of FS9 is arranged in LOD5-sized areas. To make a complete rework of FS9 terrain, nearly all the files that comprise the LOD 5 area would have to be remade, and the default files disgarded for that area.If you determine the area you want to rework is numbered *924160*, then the following files should be replaced:HP924160.bgl ......... the LWM polygons with their elevational properties ( might as well remake them from mapped or GIS data ).HL924160.bgl ......... the shorelines to match the hydropolys.RD924160.bgl ......... the roads, so they now go where they are supposed to go, from maps or GIS data.RR924160.bgl ......... railroad tracks same reason as the roads.UT924160.bgl ......... same for the utility paths.ST924160.bgl ......... don't forget to replace all the streams.Simply excluding the roads, rails and streams still leave the old "footprint" altering the mesh. And remeshing now is becoming too difficult as there is so much being altered by lakes, rivers, streams and roads.So make new ones to replace the defaults, and get rid of the old flattenings left behind.And don't forget to make new mesh for the area ( a slight overlap of the surrounding LOD5 areas would be prefered ). We have access to a great deal of SRTM data now, and it makes a good mesh.Then you have the whole project as good as it can get, terrain-wise.With all the LOD5 sized areas in the world, it's not likely we'll all end up reworking the same areas. And there are enough areas to keep us busy until the next FS version. ( Unless someone develops a good GIS-based program to automatically create LWMs, roads, and all, to speed up the process ).Dick

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... and we expect daily progress reports from sunny FloridaAfter all, a LOD5 section covers only about 100,000 square kilometers :-eekI know I keep saying this but the lake flatten tutorial should be out shortly. It would have been out already, if Steve wasn't insisting on making his updated utility the mother-of-all flatten tools ;-) (if he ever tries to lure you into beta testing you better drop whatever else you're doing - I'm currently looking at beta version 12!!!). The tool and tutorial will give you a better idea about how to go about replacing those pesky default files, though I can't shake the feeling that Dick's post was just a tad facetious, right Rhumba? :-badteeth More to the point, the flatten utility will give you the option of making fairly precise elevation changes to land and water section (though they all will be flat 'terraces'), which is probably more in tune with the scope of your project. Other than that, you'd have to go the MicroDEM edit-your-mesh route, or a similar procedure with the raw elevation data.Cheers, Holger

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Based on your response (thanks, BTW) I am becoming more and more outdated. I thought (hoped) that there might be (preferably, in ASCII format :-hmmm ) an array of elevations and Long/Lats one could simply define and submit to a routine which would punch out a bgl which would supplement/complement the large default one. This would allow all of us to patch up the little annoying anomalies that unavoidably creep into any surface curve fitting routine.After all, the code for flattening basically does the same thing...you can define longs and lats...and one altitude, and now you have a different surface.........so it is not clear to me why someone in Microsoft won't produce a routine like this which would simply allow us to "redefine the surface" differently for every 10m or so for those of us who would take the trouble to fix the local anomilies.More directly, I wonder if my ? about the apparently flattening of lakes would allow me to use something like Ground2k to create a "lake" where I would want to flatten the terrain (that is, under a photorealistic river) so that when the photoreal textures of the river are laid down, the river will have the "lake" directly underneath, and will thus always be flat, albeit with steep sides...

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..." and we expect daily progress reports from sunny Florida."It is hotter than Hades down here.......:-violin I actually have accomplished some very looking GMAX stuff...but the file upload limit on AVSIM won't do it justice...maybe in the screen shots forum ...soon....very soon...no, maybe late December....one of the problems I have is that I have no real face to face contacts with other designers...I know I could bring someone up to speed 10x faster than I did learning GMAX or Paint Shop Pro.Rhumba/Holger/Bernstein/nudata/greenwood/et al we have some very nice places down here for sale www.pennbrooke.com.Sorry to say, though, mesh terrain redesign is not in the cards for me.

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Hi Holger.Actually I'm not being anything but serious. I can take Tiger data and break it down into LOD6 areas ( 4 needed to make an LOD5 ). These can then be made as 9734 x 7301 bitmaps for use with Ground2K. The data is a bit course at that resolution, but I think it is workable.I hope in a month's time to replace a full set of the pesky LOD5 misplaced water and roads, add some SRTM 1 arc sec mesh, make some new landclass ( although Justin Tyme's is really good ) and have at least a small part of the world as it should be.But that is for an area near my home. To do the entire earth would take some time. There are 6144 LOD5 areas on earth, and if 35% are land... that's 2150. At 12 per year, that's 179+ years to cover the earth!So until we have a program that will translate GIS data, or until MS tells us a secret of how to get rid of flattens by an exclude, it is a good exercise in patience. ;)Dick

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Hi Dick:the Zen of add-on design - count me in! (and I'm serious too; every time I see a stream run up and down a mountain, I cringe. In fact, I have disabled a whole bunch of ST9*.bgl files in mountainous areas with add-on mesh.) I'll probably stick with satellite imagery as Ground2K base maps. I completed a small step-by-step guide and associated Excel spreadsheet for translating the geotiff UTM format into lat/long WGS84 via Global Mapper (demo version) and Photoshop or Paintshop Pro. Should I upload this?Cheers, Holger

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