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regional textures

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I see in the recent MSFS Global Terrain presentation at GDC that there are "23 regions" for MSFS. I assume this is a reference to FSX. That would be nice. However, a problem in the past is limited texture support for the regions. Is there going to be some improvement on this front in FSX?In FS9 many landclass / region texture lookups result in the North America region b textures getting loaded.scott s..

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The goal is to increase the number of regions from the 10 that were available in FS9. It sure would be nice if the regional texture lookups were customizable, wouldn't it? I'd sure like to see that happen, but I don't know if it will.-Adam

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Thanks -- and Adam,I really thank you for your paper/presentation posted on FSInsider. It brought together some bits and pieces that others have written on, as well as adding some stuff I had never seen before. For example, computing the error term for ocean elevation points -- first I ever knew of that.I've been going over and over the paper, in relation to the fs9.cfg terrain option lines which IMHO are cryptically explained in various "tips" posts, including the one posted on FSInsider.In particular:# TERRAIN_ERROR_FACTOR=96.000000This is a value from 0 to 100 that control the DEM radius (it is linear in area)# TERRAIN_MIN_DEM_AREA=10.000000This the lowest value used to calculate the DEM radius based upon the TERRAIN_ERROR_FACTOR# TERRAIN_MAX_DEM_AREA=100.000000This is the highest value used to calculate the DEM radiusI take it these are used as ipouts into the error term, and maybe also control how many cells at each LOD are loaded into the scene graph?And then again:# TERRAIN_EXTENDED_TEXTURES=1This turns on/off the extended texture ring# TERRAIN_DEFAULT_RADIUS=This is the default radius in textures for all rings, default is 2.5# TERRAIN_EXTENDED_RADIUS=This is the radius used for the inner ring when the extended texture ring is turned on, default is 4.0# TERRAIN_EXTENDED_LEVELS=This is the number of rings to add when using extended texture rings, default is 1I always thought these had to do with which mip from a terrain texture would be used, but can't demonstrate that in my testing. So I was thinking maybe this had to do with the tesselation/rendering of the mesh triangles, rather than the texture mips per se?sorry for the topic drift.scott s..

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Ohhfmmmsm... You're making my brain hurt! No one on FS team really knows how those settings worked so we ripped them out after we shipped FS9. Expect the terrain settings to be different in the future. -Adam

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Guest Seadog

Hello, AdamIt's slim comfort to know we aren't alone in finding those settings confusing, but greater comfort to learn something more understandable may replace them.In your paper and PPS presentation, however, you note that the scene graph radius is user selectable between 2.5 and 4.5 cells. Does that refer to Terrain_Default_Radius? If so, does that militate in favor of a corresponding setting for Terrain_Extended_Radius when extended textures are turned on?And in your PPS document, it notes that High LOD = small radius, while Low LOD = large radius. Does that mean that using Max Vertex Levels of 20 or 21 militate in favor of setting scene graph radius to the lower end of the 2.5 to 4.5 range, in whichever of the settings that pertains to?Thanks for whatever insight you can furnish.-Seadog

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That 2.5 to 4.5 cell line is exactly what I jumped on. The reason is that I've been playing with texture mips, and I always thought that was controlled by those terrain lines, but I set them to all sorts of things and get no change in the mip loaded. So that line in Adam's paper made me think I was looking at it all wrong. Here is what I see in mipped textures (DXT1 with different colored mips, yellow is 256x256 etc)http://forums.avsim.net/user_files/146671.jpghttp://forums.avsim.net/user_files/146672.jpgscott s..

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SeaDog,Ohhhh, my brain still hurts after reading this. :-)TERRAIN_DEFAULT_RADIUS and TERRAIN_EXTENDED_RADIUS are two things that we ripped out of the code after shipping FS9. I'm not really sure how they worked.In my PowerPoint slides when I talk about high LOD cells having a small radius and low LOD cells having a large radius, I mean that we pack lots of detail (high res mesh and textures) into small cells that exist in close proximity to the camera and we put less detail (low res mesh and textures) into larger cells that extend further away from the camera. Look at Scott's colorful screenshots above. Note the yellow cells, which are about 1 kilometer across, only extend out a short distance from the camera. The yellow cells contain the highest resolution data. Extending further out are the green cells, which are actually twice the width and height of the yellow cells and have half the detail (pixels are twice as big; mesh points are twice as far apart). Even further away are the blue cells which are 4 km by 4 km. The white cells are 8 km by 8 km, and so on. Don't be confused by the chiseled-looking squares in the screenshots because they are all 1 km in size and they don't indicate the true size of the cells the terrain engine is using.-Adam

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Guest Seadog

Hello, AdamI really appreciate the candid, straightforward response about the TERRAIN settings. And thanks for making clearer the import of your PowerPoint slides. I'm really looking forward to FSX.Thanks again for the courtesy of your reply - Seadog :-)

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