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Question about LOD (Level of Detail)??? Using SRTM

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First of all I wanted to publicly thank Matthew Styles for his wonderful program to convert SRTM data to BGL files it makes it so easy, and works great. Also wanted to Thank Steve Greenwood for some good advie at his web site at http://www.fs-traveler.com and many resources.Anyway because my home state is WEST VIRGINIA (Almost Heaven), when flying over it I wanted to see the beautiful rolling hills. I ran Matthew Styles's program on the 3arcsec data at LOD=9 and the New River Gorge looks more like a Canyon. Then I ran it at LOD=8 and it looks better, that at LOD=7, which I think is a good compromise.I am enclosing a JPEG comparing the 4 settings and they are:Top left(3arcsec LOD=9)-Top right (3arcesec LOD=8)-Bottom Left (3arcsec LOD=7) and Bottom Right FS2002 Default).I think I will settle on LOD=7 and would like any advice or opinion?

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The sheer drop-offs are being caused by the default LWM ( HYP ) polygons. They have height data, and are mis-shapped/mis-located.There is no good "fix" for this in FS2002. The default HYP.bgls are flattening the water surface, and even after making overriding water polys, the default elevations persist.It would be possible to replace the poor LWM water and VTP shorelines, but the process would involve a LOT of work with Ground2K or Coastline Maker or AutoASM... and you'd need to use Tiger data ( shp files ) and create a map for the water data... probably overlayed onto a map from TMFViewer ( of the original BGL ).This is possible. One further problem is that the river and shorelines would not meet the default at the edges of the replacement BGL.It is also possible to attempt to "remesh" the default land heights, rather than replace the entire default BGL. A new river course could be made, and the cliffs caused by the default BGL(s) remeshed. Conceptually, this is a better solution. But in practice, remeshing has given mixed results. It's more art than science, and doesn't always look right.Ground2K can remesh with invisible elevations as a 'remesh' function. It can also make a topological looking series of stacked LWM land elevations.Steve Greenwood has found that there is just as good a case to attempt remeshing with SCASM's Area16n polys. The framerates are similar, and in at least some cases, may be better with the SCASM-derived code. The SCASM code should be 'stackable' as well... or a grid of adjacent heights made, like Ground2K's remesh function.The trick to remeshing is too keep the difference in elevation between polys as small as possible, to avoid a stepped, over-sampled look. Smaller polys or closer topological stacks might help.So there are basically 3 solutions:Use the default water, and remesh.Make a new river, and remesh the default elevations left over ( the water disappears, but the elevations stay ).Replace the entire default HYP.bgl with the correct water and height. It might be posible to set the height to -9999 ( no-height ), and let the mesh handle the elevations.==============Hopefully FS2004 will have better mesh and water data, and a means to restore mesh on replacement of a default water poly ( after it flattens the mesh ). Dick

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I'm glad to see you got the mesh to work. As Dick has indicated, there is little we can do about the shorelines, but at least now you can adjust your mesh to suit your own preferences. :)Steve

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dlhusk;I have TerraScened the entire state of West Virginia and sourrounding area with Near Photo Quality scenery, sadly with no Autogen. Attached are two shots, and notice the river is must closer to actual width than default. Also the New River Gorge Bridge constructed by a friend in New Zealand after I sent him several photographs and drawings. My scenery ios nearly 5GB, I only wish I had autogen. If you want some CD's and the Bridge send me an email and your address!richardlhll@wmconnect.comRichard;

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Dick, Thanks for the good info, but actualy I was speaking of the banks of the river. On the right on the it looks like Grand Canyon at LODF=9 but at LOD=7 it is more like it actually is (Cliff/Rolling Hills)...Appreciate it,Danny

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Thanks, Steve. As I told Dick it was the banks/cliffs more than anything.Danny

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Richard, Love the BRIDGE!!! Awesome! Looks nice. I sent you a seperate email about price of Terrascene. I wondered if it could be used with FS2002?ThanksDanny

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