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KDFW Sink-Hole Problem

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I have TerraScened the Dallas area. I then loaded in Wayne Roberts' new DFW airport and was all ready to taxi for takeoff until my 757 simply sunk into an invisible hole in the taxiways. After experimentation, I saw this happen at several places on the way from the terminal to the runways just east of the terminal area.I attempted to use Flattenator on the raw DATA files and re-pod the area, but I'm not sure I fully understand how to use the tool, even after reading the instructions from Harald Kraft.Anyone who has used TerraScene to create ground textures and has "fixed" the area - please post help instructions. I fly (in real life) to and from Dallas every few weeks. I was looking forward to flying my flight path today. Oh well. But maybe it'll be fixed soon.Thanks for the help.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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If you follow the thread on Nice, you will see that a few things need to be done in order to prevent sink holes or water instead of land. You need to learn about Ground Transform, Terrashape and see the extent to which you can fix it. I still am experimenting with these program and don't know enough to help you.tony

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I read the NICE thread, including the additional related posts. But I think this might be a different problem. This problem, I would suspect, is occuring b/c of some bad data TerraScene is picking up and using to build the scenery. I can't be sure of that, but I'm going to test removing the TerraScene work I did, to see if everything appears fine. I'll post back as soon as I confirm.Now, I may need to manually edit something, but I'm just not sure how to do it, or for that matter, what exactly to do.Let's keep our fingers crossed. Maybe someone has seen this before and can better define the steps needed to fix it.Thanks though.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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I confirmed - this problem ONLY occurs when I have the custom TerraScenery installed. When I removed this and left the ground textures to the default, I can taxi anywhere. Wayne's airport TerraModels scenery has no affect either way.Thus, the problem described in the NICE thread does not appear to be the same problem here.Thanks though for trying. Any help is better than none. And I may just fix NICE while I'm at it!-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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I've seen this before, at KDFW, but I haven't taken the time to try to fix it. The problem is that KDFW spans two globe tiles (186152 and 187152), and for some reason the elevations at the edges of these two tiles don't match up when you slice them. What you should do to fix it (I think) is manually edit the elevations for the super tiles in which KDFW resides at the edges of those two globe tiles.As a quicker work around, you can use your terrascene scenery without importing any DEM data as the default elevations don't have this problem.nick

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Nick is on the right track. I ran into this problem when I Terrascened D/FW a few years ago. The sinkhole exists where the taxiway crosses the globe tile boundary. Fly attempts to match up the elevations along the edge where two globe tiles meet so they are seamless. The problem at KDFW is that the one of the runways is right by the edge of the globe tile so when the editor flattens the runway it offsets the matching of the globe tile seam creating a sinkhole right where you taxi across the globe tile border. I don't think this can be fixed. As Nick offered, using the default elevation data eliminates the problem and, since the D/FW area is relatively flat, you don't miss it.

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I didn't notice this problem at KDFW but I did run into the same problem converting Simflyer's KIAD. In addition to this problem, I had a conflict with default scenery, that's why you'll see that there's also an .S11 file included. You can find the fix for KIAD here:http://members.cox.net/aamigorena/data.zipAs soon as I have some more time, I'll try to fix KDFW.Alejandro AmigorenaCheshire, CTFly! II Beta Team MemberAthlon XP 1800ABIT KR7A-RAID768Mb RAMMSI GeForce 3 Ti 500 64MBSB Audigy GamerCH Flight Yoke USBCH Pro Pedals USB

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I am pretty sure this type of problem can be fixed with Flattenator. The Advanced options appear to be able to address this problem. The only trouble is that even after reading the instructions, I'm not sure I understand what to do.Maybe we can get Harald Kraft and Ken Salter involved with this thread. I'll send them each a message today.-DK---David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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I don't have any real experience with Flattenator to say one way or the other but if it functions as a bulldozer where the entire area along both globe tiles can be flattened to the same elevation so that the seam between the two is good and the runway is flat then it might work . Since the terrain elevation doesn't vary much in the Dallas/Ft. Worth area I'm not sure it is worth the work involved though. I took the easy path, I just TS2ed the area using the default elevation data and I can't tell the difference. It will be interesting to hear how this turns out.

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Hi DavidI got your email.KDFW uses the tiles 62/45, 63/45, 62/44 63/44 in global tile D186/152. (You find their elevation data in supertile 7,2 in the D186152G11.TRN-File)and the tiles 0/45, 1/45, 0/44 1/44 in global tile D187/152. (supertile 0,2 in the D187152G01.TRN-File).1.) open your DataD186152G11.TRN-File and search for -- super tile 7 22.) look, if this supertile contains high detail grid data. This section starts with -- high detail grid3.) Remove all sections in this supertile. Leave one ========== END OBJECT ========== after the elevation data before the next -- super tile-entry.4.) Do the same with supertile 0, 2 in the D187152G01.TRN-File.5.) Try, if the sinkholes are gone (Searchpodfirst=0)6.) If everything is okay, I will help you to edit the high detail grid manually.7.) If this does not help, change the elevation data for point 8, 9, 10, 13, 14, 15, 18, 19, 20 (First point has index 1) in the DataD186152G11.TRN-File and for point 6, 7, 8, 11, 12, 13, 16, 17, 18 in the DataD187152G01.TRN-File to the exact same number.8.) Try, if the sinkholes are gone (Searchpodfirst=0)Harald

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Well, I'm home sick today, so I decided to mess around with this a little bit. I think I've got it fixed. I hand edited the .trn files that are under KDFW. The problem with Flattenator is that it doesn't work on 8x8 sliced scenery. At least it didn't before. Someone correct me if I'm wrong.I resliced the elevation data for 186152 and 187152 this afternoon with a 8x8 grid and a tolerance of 50. For some reason the slicer really screwed this up. Within 186152, g11.trn, super tile 73 some of the "sub-tile" high detail data didn't even agree with the super tile vertice elevations. The edges of 186152, g11.trn, ST73 and 187152, g01.trn, ST03 didn't match at 3 of the 5 shared vertices!I edited those to match up and did very little testing (too tired already), and I think I have it fixed. One area that is probably still a problem would be at the very south end of the airport (maybe outside the airport), but I don't think there are any taxiways/runways at the seam there. The reason this could be a problem is that I got 8x8 high detail in that tile in 186152 and no high detail in that tile in 187152. Because of that, they don't match exactly as I didn't take the time to hand code a detailed 8x8 area for 187152.Just to get you going, you can download the updated terrain files at:http://users2.ev1.net/~nik2/KDFW.zipIt is a little over 80Kb.While doing this test, I've also finally figured out where my shadows have gone. Has anyone else noticed that the aircraft shadow disappears when it is in any sub-tile (ground tile) that contains high detail elevation data? I've only seen that the shadow breaks in 2x2 and 8x8 high detail areas. I haven't checked 4x4 areas, yet.I'd like to write this up in more detail, basically covering the entire .trn file structure, and expand on Ken's work and the "flatten help.xls" file I found out there somewhere, but it's not going to happen today. :-erks Is there a table of the tile "types" somewhere?nick

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Geez, I took so long typing that Harald beat me to it! lol Those super tiles should be 7,3 and 0,3 though.nick

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Nick/Harald:Thanks. I am now in Dallas (on business) and went out on the tarmac yesterday with a shovel... just kidding.When I get back to NY, I'll attempt this exercise on my own. Not sure I fully understand what I'm doing, but I'll do what I can. ALL: If anyone else fixes the problem using these instructions, please post results. Knowning my work schedule and the fact that when I get home, the last thing my wife and kids will let me do is sit in front of the PC to try to do this, I think it'll be a week before I get this done.BTW: What does Flattenator do? I thought this was the purpose of flattenator.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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This may be a simplistic explanation, but I'll throw it out there. ;-)Flattenator is an interface to help you edit the elevations in the terrain files. The problem is that it breaks if you try to edit a terrain that was sliced with an 8x8 grid. If you stick with 4x4 or below, it works great.nick

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What is the default grid size for TerraScene? 8x8? Is 8x8 higher resolution than 4x4? This is all quite complex for me. I just use TerraScene and fly there. I never got into editing and all the other manual work around TerraScene that would probably be really good to understand, but which I never really got.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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I believe the default elevation slicing is 4x4 with a 500 foot subdivide tolerance. That information is under the "Advanced" button below the "Slice with Fly" checkbox on the render window. I think that's right. I can't see it as I'm at work.I'll give a quick rundown of the divisions here. This is what I would like to put in a documant about this stuff....Each globe tile is divided into 4 quarter globe tiles. Those are what the g**.trn terrain files represent. Each quarter globe tile is divided into 64 super tiles. Each super tile contains 16 ground tiles. The ground tiles are numbered relating to the quarter globe tile, therefor the indices of the ground tiles run the range (0,0) to (63,63) to make up a grid of 64x64 ground tiles. Each of these ground tiles has 4 elevation points, one at each corner, but they are recorded in the .trn files related to the super tile. That means that each super tile contains 25 elevtation points (a 5x5 grid that represents the corners of the 4x4 grid of ground tiles). Now, within each of the ground tiles you can have high detail terrain data. This data further divides a ground tile (the smallest tile I've referenced so far) into a 2x2, 4x4, or 8x8 grid. To take the simplest case, if you slice 2x2 detail into a ground tile its elevation is now represented by 9 points instead of 4. There are three points on each edge (with the corners being shared of course) and one in the middle. 4x4 gives you 25 points, and 8x8 gives you 91 points. Som with the 8x8 high detail grid you can get the ground that is affected by the elevation data down to a pretty small area. I haven't calculated how small, though.Like I said, I'd like to put all this info together with lots of pictures. I just need to take the time to do it.Hope this helps some more,nick

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David - I have been following this discussion and I have gone to KDFW.From your pictures it appears that you get that sinking feeling at runway 17L or 17C. I have taxied in that area but do not sink out of site. Am I in the right area? I would like to correct this, but can't find a problem.

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Wayne, at least in that second pic he is between 35L and 35C. That makes sense because that is just east of the seam between the two globe tiles.nick

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Okay. I read your notes. I will try method one in a minute, but I was studying method 2 - manually synchronizing the points across the two globe tiles.I'm not sure what you meant by "change the elev data for point 8, 9, 10, 13.... etc.Here is a portion of the HDTL for 7,3 in D186152G11.TRN: -- super tile 7 3 ========== BEGIN OBJECT ========== -- dimension in tiles 4 -- tiles in this grid are this type -1 -- indeces in parent grid 7 3 -- texture list ========== BEGIN OBJECT ========== -- texture list 16 DATAd1861526EF495BC.RAW DATAd1861526EF495BD.RAW DATAd1861526EF495BE.RAW DATAd1861526EF495BF.RAW DATAd1861526EF495FC.RAW DATAd1861526EF495FD.RAW DATAd1861526EF495FE.RAW DATAd1861526EF495FF.RAW DATAd1861526EF4963C.RAW DATAd1861526EF4963D.RAW DATAd1861526EF4963E.RAW DATAd1861526EF4963F.RAW DATAd1861526EF4967C.RAW DATAd1861526EF4967D.RAW DATAd1861526EF4967E.RAW DATAd1861526EF4967F.RAW ========== END OBJECT ========== -- texture grid references 0 4 8 12 1 5 9 13 2 6 10 14 3 7 11 15 -- night texture list ========== BEGIN OBJECT ========== -- texture list 3 DATAd1861526EF4963C5N.RAW DATAd1861526EF4967D5N.RAW DATAd1861526EF4967E5N.RAW ========== END OBJECT ========== -- alt (MSL) for each vertex 592. 544. 603. 603. 544. 596. 588. 603. 603. 587.27032470703125 556. 552. 603. 603. 587.27032470703125 612. 644. 603. 603. 587.27032470703125 596. 620. 603. 603. 556. -- high detail grid ========== BEGIN OBJECT ========== -- dimension in tiles 4 -- tiles in this grid are this type 1 -- indeces in parent grid 1 0 -- alt (MSL) for each vertex 544. 603. 603. 603. 603. 556. 603. 603. 603. 603. 580. 603. 603. 603. 603. 592. 603. 603. 603. 603. 588. 603. 603. 603. 603. ========== END OBJECT ========== -- high detail grid ========== BEGIN OBJECT ========== -- dimension in tiles 4 -- tiles in this grid are this type 1 -- indeces in parent grid 2 0 -- alt (MSL) for each vertex 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. ========== END OBJECT ========== many lines deleted -- high detail grid ========== BEGIN OBJECT ========== -- dimension in tiles 4 -- tiles in this grid are this type 1 -- indeces in parent grid 3 3 -- alt (MSL) for each vertex 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 603. 556. ========== END OBJECT ========== ========== END OBJECT ==========What is it specifically I'm supposed to synchronize? I'll post in a few minutes if method one works (full deletion of HDTL sections....-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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Just ran Fly. Good news is that with the edited G11 file, I can now taxi from the terminal to the runway without "falling" into the ground. But two things:1 - I couldn't locate any HDTL area in 0,3 of G01.TRN:[/i] -- super tile 0 3 ========== BEGIN OBJECT ========== -- dimension in tiles 4 -- tiles in this grid are this type -1 -- indeces in parent grid 0 3 -- texture list ========== BEGIN OBJECT ========== -- texture list 32 C2958D8D00 957E8D7E01 7E7E7EA802 7E95A87E03 8D8DC29510 8D8D957E11 8D8D7E7E12 8DC27E9513 8DC28D8D20 C28D8D8D21 8D8D8D8D22 8D8D8DC223 C28D8DC230 8DC2C28D31 C28D8D8D32 8D8D8D8D33 6F8D2C00.RAW 6F8D2C01.RAW 6F8D2C02.RAW 6F8D2C03.RAW 6F8D2C40.RAW 6F8D2C41.RAW 6F8D2C42.RAW 6F8D2C43.RAW 6F8D2C80.RAW 6F8D2C81.RAW 6F8D2C82.RAW 6F8D2C83.RAW 6F8D2CC0.RAW 6F8D2CC1.RAW 6F8D2CC2.RAW 6F8D2CC3.RAW ========== END OBJECT ========== -- texture grid references 16 20 24 28 17 21 25 29 18 22 26 30 19 23 27 31 -- alt (MSL) for each vertex 544. 564. 516. 476. 448. 556. 532. 496. 444. 448. 556. 516. 476. 444. 436. 544. 544. 520. 496. 424. 556. 500. 508. 492. 428. ========== END OBJECT ==========[/i]Second, by editing the first file, I now get that "bug" that used to exist in fly where your plane appears to slowly sink below the surface of the runway as you move along the ground. See a screenshot below....So, I think I need the help with method two as I noted above. I would guess manually "fixing" the seams between the two adjacent tiles will do the trick, but in both cases, the HDTL elevations must be left in.NOTE: First picture demonstrates the very out-of-scale size of the runway. I accept wide runways, but this is clearly visually incorrect. On the final two pix, the shot was taken at exactly the same place (parking brake on).FINAL NOTE: I tried Nick's KDFW.zip file (referenced several messages above), but had no luck. See some pix I posted under his message.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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The two shots below are after downloading the file above. It did fix the sinkhole, but the elevations need to be fixed to match the taxiways.Hmm... this appears to be much more work than I thought.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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This is the last post of the night. I'm tired.I ran Flattenator again. I selected KDFW and hit "go" (or whatever it is). I then launched fly with the edited Gxx.TRN files in the right place. The sink hole is gone! That's good. But like with Nick's edits, I slowly duck under the taxiways and runways as I taxi eastward. So it appears that Flattenator is working properly, but it is gradually synching the elevations. Since the runways and taxiways are at a fixed height, as I slowly sink, the runways and taxiways remain at the default height, thus begin to rise.So here's the solution as far as I can tell - Level the entire airport at the height of the terminal (which appears to be correct). I would guess that means copying the elevation data from one super-tile part of one of the Gxx.TRN files to the other super-tile in the opposite Gxx.TRN. If I've learned anything from all the above, I would take the data from G11.trn (7,3) and copy it to G01.trn (0,3). But given that there was no HDTL data in G01.trn (0,3), not sure if that is correct.I'll look for responses tomorrow. Regards all.Hope nobody minded my single-subject posts tonight. I kept trying different things between dial-up sessions.PS: Nick suggested I re-TerraScene the files without DEM data. If I do so, won't that remove the shadows? I thought you needed DEM data to get ground shadows. Although, maybe this is not a big deal b/c Dallas is pretty flat anyway.-DK---David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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Hi DavidI never had this slowly sinking problem, so I don't know the reason.There is no problem with the missing HDTL data in tile 0,3, as long as all HDTL-points in 7,3 defining the seam between 7,3 and 0,3 have the same value (which should be no problem, because the airport is flat.If the area is not flat, you have to interpolate the HDTL-points to make those 2 supertiles fit exactly.for example:The altitude of the corners of your supertile is: 100. 500.and only one supertile has a 4x4 HDTL, than those HDTL-points on the seam must have following elevations: 100. 200. 300. 400. 500.or sometimes you will get strange effects in Fly.Does that make sense ?To avoid problems, I recommand to make the airport entirely flat.Harald

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Not sure I understand above. Please forgive me for what appears as a mental block!Last night, I kicked off TerraScene again, this time skipping the import of all DEM data. I am at the office now and didn't have a chance before work this morning to try it out (lots of Snow fell last night in NY so I unexpectadly had to dig out my car to get to the train station).I will try flying tonight with this revised TerraScenery at KDFW. According to Nickster, this should solve my problem, even if it is "cheating" a bit. I will report back tonight or tomorrow.In the meanwhile, I will keep studying the relevant files side-by-side. Perhaps this will clear the current mental block I seem to be having.-DK----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.

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