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Coastline Maker - concave polygons ?

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I am attempting to use Coastline Maker to create LWM polygons to overlay lakes onto the VFR Photographic Scenery. I have created a merged bit map showing the grid from CellGrid overlayed onto the photographic scenery lake outline. The next step is to digitise the lake edge but it is obviously not convex. See:Cropped2.jpgIn the instructions for Coasline Maker, under Caveats and Limitations it states that LWM polygons should be convex in shape. However, the next graphic shows a "comma" shaped lake which is obviously not convex.Can someone explain how this was constructed.George

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>"the next graphic shows a"..... >>Are we missing a pic here?>In the instructions for Coasline Maker, under Caveats and Limitations:Islands.jpgGeorge

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I'm not using Coastline Maker, but coding my own files using BGLC. In FS2004 concave polygons seem to work fine. So no need to worry about splitting them. I think the SDK stated that VTP polys should be convex, but LWM can be concave. Anyway, VTP can be concave also at least in FS2004. Still have to find a case where a concave poly doesn't show...Cheers, Christian

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Hello George,Custom terrain (photo-realistic ground textures) supercede and replace all LWM and VTP polygons. It is not possible to overlay an LWM Water Mask on photo-real scenery. The only thing you can do is create an alpha channel for the textures so as to reveal water.Best regards.Luis

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>Hello George,>>The only>thing you can do is create an alpha channel for the textures>so as to reveal water.>>Best regards.>>Luis>Hi Luis,You have just dashed my hopes, initially I was only trying to create a flatten area for the lakes to force the area to be at the correct height. Steve Greenwood kindly supplied me with an asm file from which I could create this. This worked to flatten the mesh. I then thought that I might create a water area in addition to make it more realistic.Unfortunately I don't know how to create an alpha channel for the textures. I would be very grateful if you could point me to information on how to do this. Perhaps you could send me an e-mail.Best regards,George

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Hello George,It is very easy to make an alpha channel.First, some explanations. Custom textures (photo-real ground) are 256 x 256 pixel bitmaps, converted to DXT format (Direct-X something or other.) DXT is a compressed image format that dramatically reduces image size. Ground textures use DXT1 format, not DXT3, which is used for aircraft textures.DXT formats can be in opaque or transparency types. The opaque type is just the bitmap converted to DXT. With transparency, you provide an alpha channel that is merged with the bitmap - this alpha channel simply indicates the areas of the bitmap that remain opaque and those that become transparent. In ground textures, transparent areas reveal the underlying water (floatable, landable Flight Simulator water.)What is an alpha channel? Simply a 2-color bitmap with pure white (RGB 255,255,255) over opaque (land) areas, and pure black (RGB 0,0,0) over the transparent (water) parts.What you need in order to do this:1) a good image editing program, although I suppose that it can be done with Windows Paint;2) an image utility that converts back and forth from normal bitmap format to DXT format. Perhaps you can use Microsoft Image Tool, although I always use either a) one of Martin Wright's wonderful programs, for example, DXTBmp or ConvIm, available on Martin's site at http://www.mnwright.btinternet.co.uk/index.htm or :( Elrond Elvish' FS Texture Converter, available in the AvSim libraryYou will also need to determine the names of the ground textures that need an alpha channel. Dick Ludowise has provided many different utilities, available in the AvSim library, that will give this information.Here are the steps to follow:1) Find the ground textures where you want to add water. For example, using ConvIm, I looked at a folder of custom textures until I found the followinghttp://forums.avsim.net/user_files/49088.jpgIt is named 011222030211100Su.bmp, and your textures will have a similar name. Make sure that you back up these textures, by making copies and placing them in another folder, before you start changing them.2) Convert the DXT texture to normal Windows bitmap format. I use DXTBmp for this, very easy to use.3) Using your image editing program, load the bitmap and paint the land parts in pure white and the water parts in pure black, as, for example,http://forums.avsim.net/user_files/49089.jpgThis is the alpha channel.4) Back in DXTBmp (or one of the other DXT image conversion programs) merge the original bitmap with the alpha channel and save it, using the original name of the bitmap, BUT make sure that you save it in DXT with Alpha format, NOT DXT Opaque.5) Place this new DXT ground texture in the original texture folder, fly, and view the results.Not complicated, but you may be disappointed by the results, as the underlying water class may not give you a water color that you like. In that case, you could try changing the water class assignments for that area, but sometimes, it is just best to leave well enough alone and not create an alpha channel (since the photo-real water color is probably better) unless you insist on landing on that lake with a floatplane.Just a note to Dick: How did you do that? I see, from George's first image, that CellGrid is layed over custom textures. It seems to be the previous version, as there are no numbers, but, still, it is surprising, since custom textures are supposed to wipe out all LWM and VTP. Tell me it is all a dream.Best regards.Luis

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Hi Luis,Thank you for a clear and concise explanation. What you have suggested is a perfect solution to my problem. All I have to do is find the two or three bmp's out of thousands to find which contain my lakes ;( >Just a note to Dick: How did you do that? I see, from George's>first image, that CellGrid is layed over custom textures. It>seems to be the previous version, as there are no numbers,>but, still, it is surprising, since custom textures are>supposed to wipe out all LWM and VTP. Tell me it is all a>dream.>>Best regards.>>Luis>Yes, it's a dream, I created the grid over the default scenery and merged it with the photographic scenery. The grid was created with the previous version of CellGrid, I've done it again with the annotated version.Thanks again,George

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Luis has just about covered it all, but one point that might be useful. You can still use polygons to easily flatten an area under photorealistic scenery so that the water (exposed by the alpha mask) is flat. I use Ground2k starting with a screenshot of the area in question. You can also use the "remesh" option to add a bit of altitude to small areas.Cheers

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>All I have to>do is find the two or three bmp's out of thousands to find>which contain my lakes ;( Hi George,This should help you, Go here to Martin Wright's website: http://www.fly.to/mwgfx/ and download TView.exe and install it to see and browse thumbnails of all FS textures as well as just about any other graphic file.There are many other great tools there as well such as Covim graphics converter, it supports all FS formats.

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Hello George,One last thing - you can use Dick's LandCalc to find the name of the textures. Just slew over the lake and read the texture name in LandCalc. Great stuff from Dick.Best regards.Luis

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Hi Luis, Paul Scott and Christian,I am overwhelmed by your generosity in spending the time and effort to provide me with the fruits of you experience.Together with the free software provided by Christian, Richard Ludowise, Martin Wright, Steve Greenwood, Ken Nelson and Iain Murray, you all have given me a tremendous start in my endeavours.I am sure that if (when) I run into further difficulties I can count on you all.Thanks again,George Davison

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Hi all,I'm back with another question. I have used Landcalc to find the scenery files at the position shown in the first post and it produces:Nw 010331120120333Su.bmpNE 010331120121222Su.bmpSW 010331120122111Su.bmpSE 010331120123000Su.bmpMy question is, how do I find which other files are between these 4 corners? There are 12,620 files in the directory each of size 43Kb compressed, 193Kb uncompressed! Is there a connection between the numbers in the filenames and their relative positions on the map? It looks to me as though there should be since they all start with 01033112012. What are the other 4 digits?Regards,George Davisonps I tried to download Landcalc2 from http://www.flatface.net/~rhumba/Zips/TDFCalculatorsAll.zip but the site seems down.

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Hi George.In a week I will have a new tool TerrainCalc2004. It will work with FS9 and will include FDSConnection.dll to place in the Modules folder, so no FSUIPC registration is needed.It will allow you to slew over the lake and you can copy the names of the files over the water you are interested in.flatface is indeed down...try this:http://webpages.charter.net/ludowr/TDFCalculatorsAll.zipWhy not e-mail me, and I can e-mail you back a beta copy of the TerrainCalc that can help you ID the names.Dick

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