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sirsanka

Need Help With Land Class

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Hi guys,I'm working in updating the land class for the Dominican Republic but I got a problem that I can not figure out.After editing the image in photoshop, I saved it as a RAW and ran resample.exeDid some trial and error to align the image with tmviewer and I got this:wordlc.bgl with my land class on top.But in FSX I get this:And this is the actual land class I worked on:Don't know what's wrong!

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Saludos Luis,It's been a while since I worked on scenery design. I got tired of seing DR so empty!.I did some googling and found http://edcintl.cr.usgs.gov/macga/dominicanrepublic.phpI wished I had found something with better resolution but it's a good start.Question, what would be a good default land class for DR? I'm using 32 (dry tropical woods).What do you thing of these values:default:32grass:32wetlands:45forests:33towns+crops:30low urban:109high urban:105comercial:101I did a program to clean up the raw image of invalid values that photoshop creates. It also places a class 30 randomly for all class 33, so you would get farms (fincas) in the forest areas.I'm also updating the afcad of MDSD to change runway 17/35 to 17R/35L and added a 17L/35R (closed for operations).

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Looks very good, Jay, and those are pretty good choices for land class values. That classification from Agricultura is probably the best that you will find on the Internet. You don't seem to have the legend for it though. It may help.Sorry, it is a little large. Just click on the image to get a larger version. Of course, an even larger image would be much more helpful, I shall see if I can find somebody at the Ministry to send me one, and let you know. You can then pretty well map almost directly from the colors to the Olson land class values in FS, with a little fudging because of the color dithering on the map.As you know, this is region R, so the ground textures can be different from expected, as well as the autogen. I did not like the polyline buildings (with courtyards) in land class 101 for this region, so I made a regional bgl file just assigning all the 101 to region B - NorthAmerica, and that got rid of the polyline buildings and gave me nice high-rises instead. Just an idea, if you want to try it.Best regards.Luis

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That seems to be the same map I'm working on. The legend will help me a lot. I did noticed a bug? in FSX...I was flying from KJFK to MDSD and during descent, FSX used winter textures and after a while it started to load the summer textures. Weird!I took the map in photoshop and isolated every color in its own layer. Some of the layers were consolidated because the legend I used is generic (NLCD).I'm gonna keep readjusting the values using your legend.My last revision was using:default:57sandy/clay/rock:131wetlands:45pastures:7shrubland:16evergreen:33deciduos forest:61mixed forest:24transitional forest:16towns+crops:31low urban:117high urban:101urban recreational:101commercial:101

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You may need a new seasons bgl for the Caribbean, Jay, although I don't remember that we display winter textures except towards the southern part of the country. Perhaps you were flying over Haiti where Winter seems to be raging in the FS world.Here is an all-Summer seasons bgl for you to try.Not really realistic since as you know we do have seasons, wet and dry. But, FS still does not represent that type of climate.By all means, please do let me try the land class, with pleasure, and thanks for offering.Best regards.Luis

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For Luis and anyone who wishes to try it.I made a bunch of changes based on the legend. I ran resample with the "Dither" option.I'm open for suggestions and improvements before I finalized it and upload it to the library.Thanks,Jay

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Looks pretty good, Jay, lots of variety and urban areas in the right place. Haven't had time for a close look yet, but the first thing I noticed is that you probably have to re-project the map. It is in UTM, but needs to be in the lat-lon "geographic" projection or it won't fit correctly on the land mass.Also, you are using a lot of 33 - Tropical Rain Forest, which is really only appropriate for the Amazon and the like. Those rain forest canopies are not found here in the Caribbean, at least not in those heights or extents. You could try degraded tropical forests or even better, crops and fields, fields and forests, or small or medium suburban wet cities that have lots of fields and forests121 - Large City Highrise is cropping up in many places where it is all rural, and there is a lot of 101 - Large City Urban Grid Wet in the Southeast that is just coconut groves.Well, I'll get back to you after a closer look later.Best regards.Luis

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Sure, Jay, you could try this:http://www.forestpal.com/image_reprojection.htmlMaybe this image should be close enough:Some more comments on the land class. Generally, that image is a pretty good indicator of land use, and you may find it interesting to map FS land class values as closely as possible to the legend values. Here are some rough indications of what I would expect to see:The coconut groves can be tough since they will not display in this region if you use Deciduous Tree Crops. But, you may remember a post of mine over a year ago where I showed how to get them by making a regions bgl just for the parts of the land class that you want to display differently.In general, I do not use any of the Rain Forest land class in the Caribbean since the trees are really too tall for us, but instead rely on Mixed Forests or the like. Even better, Forests and Fields or the Suburban Wet values have plenty of trees and small towns, and are perhaps the best match.Best regards.Luis

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Luis,I finally converted the RAW into a GeoTiff but it took a lot of work. I have another version for you to try which is much closer to what you said but still I have more tweaking to do.Also check out MDST. It's surrounded by Mangroves. I'll try to get it fix in the next round.

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Hi Luis y feliz ano nuevo!. I'm strugling with how to align the image. Can you show me how you did it? I used glwarp to reproject but is not good what I'm getting. Good news is that I used your Region trick with excellent results!.Thanks

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Luis,Do I have to redo the coastlines in order to align the land class as you just shown? I guess that would be the way to go.

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Hola Jay,No, you should only have to re-project the RAW image for everything to be right.Probably the easiest way to do this is with Global Mapper where you can geo-reference a file and re-project it in quick and easy steps. Unfortunately, this program costs money, so I use a free program, Hyper Cube, to warp the image instead. Re-projection is just another way of saying that the map is warped, anyway.Hyper Cube is probably overkill, as it is extremely powerful and really made for other things - still, it does the job with no hassles.The technique is to warp the map to conform to another image that one knows is the correct projection.I use SBuilderX to get that, since it takes the images from Google or Virtual Earth, that are in U.T.M. (Universal Transverse Mercator, and in this particular region, that is North 19) and automatically converts them to the required Geographic coordinate system, the so-called "projection" that is needed.So, I choose the "Add Map from Background" option:Then, select the area desired - the coverage and dimensions of the two images, the original and target, should be as close as possible.Once the image is created, I compile it into photo-scenery just so that I could have the inf file that SBuilderX creates.That inf file will come in very handy at the end of the process.Everything is now ready for Hyper Cube. Unfortunately, this program does not like the BMP that SBuilderX creates, so I just convert that to a JPG, no problem.Here is the JPG for your use, if you wish. It is in the required Geographic projection.And this is the inf file:[source] Type = BMP Layer = Imagery SourceDir = "." SourceFile = "L8X153X158Y227Y230.BMP" Variation = All NullValue = 255,255,255 SamplingMethod = Gaussian ulyMap = 19.9733487861107 ulxMap = -72.421875 xDim = .00274658203125 yDim = .00260220790951228[Destination] DestDir = "." DestBaseFileName = "Photo01" DestFileType = BGL LOD = Auto UseSourceDimensions = 1 CompressionQuality = 85In Hyper Cube, just load the original image and the target, one after the other, then select the Warp function.I have loaded the vegetation map and will warp it to the SBuilderX image, but you should load your land class image instead as the original. Then, in Warp, place points on each of the images in turn at the same spots (make sure to Shift-Click). Also make sure to choose Affine and Cubic as these are the most appropriate choices for this process. The Affine transform needs a minimum of 4 common points in order to warp the image, but that won't give a good result. Instead, I went all around the coast, placing points, 2 dozen in all, at all the salient points and extremities. Any more is probably overkill. This gives a very good "re-projection" for the money.You will wind up with a new image that you can save and use. It may have a band of black around it, since the original will be transformed to the same dimensions as the target, but you can just make that black into the Null Value.And your land class values may have been dithered, so you will also have to take a close look at them as well to make sure that everything is fine.The biggest problem is that the new image does not have the same dimensions as the original, so your inf file is no longer valid. But, the inf file that SBuilderX created will work perfectly - simply change the Layer to land class.The whole process is relatively easy and should give you the re-projected result that you need.Best regards.Luis

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Made good progress thanks to Luis! I still have to futher align the image but we're getting there. Here's the lastest.

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