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larshgf

Missing mesh-scenery

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Hi all you patient mesh-guru's! In Ground2k4 I have redrawn one of the Sporadic islands (Skiathos) in the Aegean Sea from a satelitte photo donated by Holger. By drawing the new coastline I found that the default coastline in FS2004 is not correct. As you can see on the attached pictures the southwest part of Skiathos is in fact missing in the default scenery. http://forums.avsim.net/user_files/66281.jpgAnd if I take a look at the same part of Skiathos from the my cessna172 comming in from west it looks like this (the yellow line correspond with the that on the map above):http://forums.avsim.net/user_files/66282.jpgIn order to fill out the missing mesh-data on Skiathos I downloaded N39E023.HGT and N39E024.HGT from "ftp://edcsgs9.cr.usgs.gov/pub/data/srtm/Eurasia" and made a BGL-file with the SRTM2BGL program. I then placed this mesh-BGL file in the same folder as my Skiathos-BGL files from Ground2K4, but the terrain is still flat on the southpart of the island. It seems that the mesh-data is not working. What's wrong here? Kind RegardsLars

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Hi Lars:now that's the kind of problem report we like to see here -screenshots and all ;-)Looking really good already - quick work!!!The mesh issue is probably due to the fact that a compiled mesh will always conform to the fixed LOD grid system it was compiled at. The straight E-W edge of your mesh indicates that the southern edge of your mesh extends into the next LOD9 cell but the mesh data don't completely fill it; thus, it won't be displayed in FS. TMFViewer is good for checking this because it only displays the parts of the mesh that will be visible in FS; not sure whether LWMViewer does that too.The solution: you need to grab the two .hgt tiles to the south and include them in the compilation.An alternative quick fix might be to re-compile the mesh at LOD10 (use the LOD = parameter in the inf file); because the LOD10 grid is smaller by a factor of 2 than the LOD9 grid it's possible, but not guaranteed, that a LOD10 mesh might include the southern edge of your island.I remember that it took me quite a while to fully grasp the concept of the LOD grid and its implication for mesh design. Check Steve Greenwood's website for more details on this (he even has an EXCEL utility to calculate the LOD grid boundaries).Another thing you'll have to do is to make a landclass file in Ground2K4 to make sure that you will have land everywhere inside the new coastline.Cheers, HolgerP.S.: and then there's the issue that the new mesh will only extend to the default coastline because everything outside of it will be set to zero by those darned default LWM flatten files. There are a few posts here that discuss alternative ways for dealing with this but... one step at a time ;-)

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Hi Holger!Thank's for a very quick answer. Things are growing slowly for me, but it's fun and I hope that I can do some design work for the FS-community as soon as I get rid of my "beginner-troubles". I'll keep in tounch.Cheers - Lars

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Hi Holger!Tried to add N38E023.HGT and N38E024.HGT to my mesh.BGL without success. Looking at the mesh-scenery in LMWviewer Skiathos is there with mesh-data and it was indeed before I included the two more south-placed HGT-files. I wonder if there can be something with the installation of my mesh-BGL or the name. I have placed my Ground2K4-generated BGL-files in a folder called Skiathos2. I then created the mesh-BGL file called "SRTM_3ARCSEC.BGL" and placed in the same folder without renamimg it. So my Skiathos-folder contains:- 0_excl_Pr_Sporader.BGL- Pr_Sporader_3.BGL- Pr_Sporader_5.BGL- Pr_Sporader_9.BGL- SRTM_3ARCSEC.BGLand the folder are placed this way in the Scenery Settings:http://forums.avsim.net/user_files/66385.jpgThe folder "SamllIsland" just contains Ground2K4-made BGL files for the little island souteast of Skiathos and Greece-SRMT contains mesh data for the whole greece. Do you see any errors in the way I installed the mesh-file?Kind RegardsLars

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Hi Lars:sorry, I didn't clue in on your remark about the missing part of Skiathos - I thought you meant the small section of water inside the new coastline.Your problem is not related to the LOD grid boundary or installation; it's the default LWM flatten that supresses all add-on mesh outside of the default coastlines.Start LWMViewer and use its "Open by Coords" function (e.g., lat 39, long 24). The program will load all default scenery files; deselect all except HP954180.bgl and zoom in on Skiathos. Everything in blue is set to 0m, the rest is mesh-clinging. Something like this:http://forums.avsim.net/user_files/66451.jpgHow to get a complete mesh for your islands? Four options I know of:1. Re-mesh the flattened section in Ground2K4 with the help of topographic maps. Disadvantage: very tedious and not always looking as desired.2. Rename HP954180.bgl (in FS9SceneryEureScenery) to HP954180.bgl.org or move it out of the scenery subfolder (don't delete it!) to deactivate it. Disadvantage: land/water transitions are now defined by the landclass and waterclass files only, which results in big square blocks of water and land.3. Dick (Rhumbaflappy) recommends to change all water elevations in a HP9* file to -9999 (mesh-clinging); see his post here: http://forums.avsim.net/dcboard.php?az=sho...g_id=1553&page= - Disadvantage: all water is now "at the mercy" of the default or add-on mesh; it's no longer perfectly flat and might "climb" up or down the shorelines.4. My approach is to de-compile the HP9* file with LWMViewer, remove the LOD8 and LOD13 sections I'm replacing with Ground2K4, then re-compile with BGLC.exe. Disadvantage: requires knowledge of the structure/code of LWM files and redistribution may lead to end-user confusion, particularly if other designers use the same approach for a nearby area.Sorry, no perfect or easy solution here: your approach is your choice!Cheers, Holger

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Hi Holger!It seems to me that the best visual result will be with your method:4. My approach is to de-compile the HP9* file with LWMViewer, remove the LOD8 and LOD13 sections I'm replacing with Ground2K4, then re-compile with BGLC.exe. Disadvantage: requires knowledge of the structure/code of LWM files and redistribution may lead to end-user confusion, particularly if other designers use the same approach for a nearby area.-I can de-compile the HP9* file and read it in Notepad. -How do I remove the LOD8 and LOD13 sections?-What do you mean by "I'm replacing with Ground2K4"?-Is this knowledge of the structure/code of LWM files too huge for a beginner like me? Where can I read about it?Cheers Lars - DK

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Hi Holger!I would appriciate very much a short description of the solution 4 you mentioned: "to de-compile the HP9* file with LWMViewer, remove the LOD8 and LOD13 sections I'm replacing with Ground2K4, then re-compile with BGLC.exe."CheersLars

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Hi Lars:sorry, but I don't think there is such a thing as a "short description" for editing the LWM/VTP code itself. To do this with a good chance of success you need to know the structure of the code as well as the meaning of the different variables, parameters, and macros. More extensive reading is in order ;-)Richard Ludowise wrote the definite LWM tutorial a while back (lwmtut.zip); many of the details have changed since then but the basics remain. Also, the FS2002 Terrain SDK, particularly the "Terrain Vector Data.doc", makes for exiting and important bedtime reading. Some of the changes in FS9 are not yet fully documented but posts here in the scenery discussion forum will get you the needed information; posts such as these:http://forums.avsim.net/dcboard.php?az=sho...ing_type=searchhttp://forums.avsim.net/dcboard.php?az=sho...ing_type=searchhttp://forums.avsim.net/dcboard.php?az=sho...ing_type=searchIf all this seems a bit too daunting right now I'd suggest you continue with the Ground2K4 work, do all those things that make the islands look realistic (accurate roads, landclass, coastlines, etc.) and leave the tricky stuff for later. Or, use Dick's option (#3), which should be much easier to implement. Cheers, HolgerP.S. By "I'm replacing with Ground2K4" I meant to only remove those cells and areas for which you provide a more accurate replacement.

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Hi Holger,I've been reading the LWM Tutorial by Richard Ludowise. If I'm going to get rid of the Area's (LOD13) that I changed during my redrawing there are a lot of lines in the BGL-source fil (=BGS-file) that must be deleted. For instance, if I'm going to delete Area "28,20" in Cell "433, 144" the following elements in the file-location which cover the "433, 144" Cell)..... LWMDataAreaDrawPolygons 1,_Transparent_,1,28,20 LWMPoly3 9, 0, _Water_, 0, 0, 0, 0 LWMPoint3 255, 158, 0 LWMPoint3 211, 121, 0 LWMPoint3 161, 96, 0 LWMPoint3 140, 91, 0 LWMPoint3 90, 96, 0 LWMPoint3 1, 119, 0 LWMPoint3 1, 1, 0 LWMPoint3 255, 1, 0 LWMPoint3 255, 158, 0 LWMDataAreaFill2x2 0, _Water_, 0, 1, 15, 0, 11 LWMDataAreaHeight 0, 0 LWMDataAreaFill1x1 0, _Water_, 1, 28, 20 LWMDataAreaHeight 0, 0 LWMDataAreaFill8x8 0, _Water_, 0, 1, 4, 0, 3 LWMDataAreaHeight 0, 0 LWMDataAreaFill4x4 0, _Water_, 0, 1, 8, 0, 6 LWMDataAreaHeight 0, 0The above is just an example. LWMDataAreaDrawPolygonsEx and LWMAreaFill16x16 must be deleted too if any.If I'm right I think I'll make a little program which can remove Areas that have been key'ed in be the user. Do you think it could be of any use? CheersLars

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