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DXT3 + Alpha problem

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Hi all,I've been doing some more tests on the photo terrain design. What im doing is use resample (FS2000) on my original aerial photo test image and on a 256 (8bit) colour mask which contains white and black regions. The BMPs are generated by resample and I use FS Texture converter to group everything into one set of textures.I first used DXT1 + Alpha (FS2002) and the thing works except for one thing. If there is underlying land in an area which is black in the alpha image, rather than getting transparency which I take it as being the underlying land in FS, the land is removed and instead I get water (default FS2002 water that is)!!If on the other hand I use DXT3 + Alpha, I simply don't get the photo image and the whole area is replaced all by water (default FS2002 water).I tried changing the alpha image to 24-bit but same thing happens. I have all updated system files for FS Texture so I can exclude that aswell.Any ideas any1?Storm

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When placing a photo with resample I think transparant areas are always filled by water. So if you want to have the underlaying terrain I think you should place them with VTP polygons.

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Not quite sure what you are trying to do but the following pics may help.BTW use Dxt1+Alpha.First pic shows an aerial photo with the water areas magic wanded out to palette black (0,0,0), from which one can create an alpha mask palette black (0,0,0)for water and white (255,255,255)for land. Only these two colours can be used, greyscale alphas like aircraft skins CAN NOT be used.The second pic shows the Dxt1 + Alpha combined and how it then looks in FS.Hope this helps. http://members.rogers.com/jkanold/jimlogo.gifhttp://forums.avsim.net/user_files/32958.jpghttp://forums.avsim.net/user_files/32959.jpg

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Hi Storm,Arno and Jim already answered perfectly, so I'll just add this. The alpha transparency in DXT1 is only 1 bit: either its ON or its OFF. It doesn't matter what your original mask BMP color depth is because the resulting conversion to DXT1 simply considers all black (0,0,0) pixels to be fully transparent and all white (255,255,255) pixels to be fully opaque - any other shades are ignored and automatically treated as fully transparent. The conversion to DXT3 and 5 will take into account and create multiple levels of transparency in the resulting texture, but as far as ground processing is concerned, FS unfortunately ignores them.When processing the resample.exe method of generated ground textures and FS "sees" a transparent pixel of any level, its been coded to simply replace that pixel with its version of water. You'd think that DXT3 and 5 with their multiple levels of transparency would allow you to show through underlying generic textures if the alpha was above 1. Unfortunately, FS doesn't support that using the resample.exe method (a feature sorely missed as it could have been used to blend photo with generic almost automatically). As Arno states, if you want that feature, you have to use the VTP poly method.Take care,ElrondPS: Heya Herr... Good to see ya. I recognize those photos! :-)

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Hi Storm.If you want transparency, you must place the resampled slices as VTP2 polygons. Both the slices and the alpha will need to be vertically flipped ( due to a bug in VTP2 display ). The texture itself will need to be 8-bit extended, mipped, with alpha.The VTP2 polys can be made by LWMDraw, Ground2k, CoastLine-Maker...The texture number for the poly would be #252 for a seasonal set ( with night masking ), or #253 for a single season. The layer number should probably be 4.Just draw the poly with one of these programs, and supply the vertically flipped slices to the texture folder. The textures will be tiled by the sim within the bounds of the drawn poly. If you draw an odd shape covering parts of 6 LOD Areas, then that odd shape will display tiled parts of the slices. ( The resample-derived names control where the slices are tiled. )A pile of Santas:http://forums.avsim.net/user_files/33037.jpgIf I just wanted to show a Santa's nose, or parts of 4 Santas, I could do that as well... the shape of the polys control the shapes displayed. BUT, with VTP2, the sim controls the placement of the tiled texture... I can't show his nose except in the center of an LOD13 Area.Dick

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I can imagine what you have going. I have no doubt it'll be spectacular when completed. As for me, same old problem cropped back up - just now comming out of the woods, so to speak.Can't wait to see the teams stuff when it comes out. Heres to ya Jim.Take care,Elrond

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Hey Jim you know if you show 'em too much I will have to.... LOL Dan

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Hi Elrond been working on some new water textures(created with Maya unlimited's fluid dynamics) with the above tool I can create any kindof water and then simply render out a .TGAbmp for use as a texture.Too bad I can't really use the fluid dynamics in FS ;-)

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Indeed it is too bad... Maybe at some point in our FS future :-).The render is beautiful - I've always loved moody nature art like that (my house is full of it). Indeed, Maya is a very creative tool for artists.Take care,Elrond

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Hi Elrond thank you very much for the comments The point is that I can make any texture I want by simply rendering out from the top view port, any colour,any time of day with any level of transparency and complete with a mask if needed . So our lake Ontario will look like lake ontario and that's way cool I think. I also plan to add proper river textures as well. And of couse you are right Maya is great tool! Your friend Dan

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