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Terrain - as real, etc.

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For years now (literally), I have been struggling with water masks that simply do not display as I would wish. Using maps as a background, I would draw the coast, but invariably it would appear strange in FS.Either the water mask would cut the altitude mesh and create ugly stone cliffs, or it would extend too far and display a coastal plain where there was none.I put it down to inaccurate maps mostly (and it is difficult to get good maps), and would then spend hours, days, no, weeks and months fussing with it and trying to get it right.Ground2K has a wonderful feature that allows for the drawing of a line while slewing in FS. So, I would slew around coasts, miles and miles of them, to see if I could get the water mask up tightly against the mesh. This never worked and either I kept getting the stone cliffs or the coastal plains, and often both at the same time.Here is an example of the sharp cliffs that appear with this problem:http://forums.avsim.net/user_files/149375.jpgAs is evident, the mesh has been cut off, so the slope of the land is not gentle and rounded, but sharp and angular.The problem is inherent in the mesh and its resolution. Consider that terrain has a resolution of about 4.8 meters per pixel, whereas mesh has a variable resolution anywhere from LOD5 (default) of 1.2 kilometers between sample points to LOD8 (150 meters resolution), LOD9 (75 meters) and LOD10 (38 meters) to mention just the most common mesh available.So, no matter how good the base map used for drawing a water mask, the coast will always cut off the mesh and create these unsightly cliffs.To me, this is not acceptable, because those cliffs do not appear in the real thing; they are not realistic. Of course, it is always possible to cover the rocky ground texture with a polygon (VTP and choose any land class you want), but this is a tedious solution. One would have to go around to every patch of rock and draw a polygon for each one. Also, this does not eliminate the angular and sharp cliff face that is not very pretty.My solution now is to draw the initial water mask with as good a map as possible, then, using the mesh as a background, extend it to just beyond the mesh (or as much as is necessary in order to avoid the sharp cliffs.)Here is a picture of an initial coast, shown over a mesh.http://forums.avsim.net/user_files/149376.jpgIt does not fit very well, which proves that either the map is not very precise or the mesh is not very accurate, and probably both. That is the latest SRTM mesh, by the way, definitely full of small errors and lack of precision. Although all mesh, by its very nature, from any source will create this problem.Now, it is a simple matter of pulling the water mask out from the mesh. But, the question is, where exactly do the mesh samples lie? Since this is a LOD9 mesh, the sample points are about 76 meters apart, and this is exactly the span of a LOD17 grid. So, using a LOD17 grid placed over the drawing (thanks to Luis de S

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Hello Luis,Thank you for your posts addressing specific problems in designing scenery!I would like to add 2 small comments. The first one concerns the possibility of using VTP polygon over the created cliffs. I am not sure, but I would think that the cliff would still show even with the covering VTP polygon. I think that FS switches to the rocky texture when the terrain slope is greater than a certain value. Did you test this cure?The second comment is that, if you are the designer/owner of the mesh, you can create an higher resolution mesh (even if you are just interpolating data) so that you do not have to enlarge very much the ground mass. I hope I will not brake AVSIM rules if I show 2 images that illustrate what I am saying:http://forums.avsim.net/dcboard.php?az=sho...g_id=2223&page=Kind Regards, Luis

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Hello Luis and Luis :)Luis Feliz, I think you are changing things!LC is

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Horst, where have you been? We have missed you.You are completely right! I forgot all about the Terrain Maximum Vertex Level setting. I always keep it at the default of 19 because of the problems that arise when placing it higher. Thank you for bringing that important point up.Please compare the first image above of the angular and rocky slope with the same thing at TMVL 20:http://forums.avsim.net/user_files/149448.jpgIt looks much better since FS is displaying more of the mesh. It still has the rock ground textures, and on a coast this means that the slope is too steep and that the mesh has been flattened by the water mask.You can see the problem here:http://forums.avsim.net/user_files/149449.jpgThere are still elevation values beyond the coast. The solution is to drag the coast beyond the LOD17 quadrant so as to allow those elevation values to display. And here is the result:http://forums.avsim.net/user_files/149450.jpgThis is with TMVL 19. There is still a little bit of rock, but I can live with it. Also, please notice how the slope on the left of the picture goes almost straight down to the water while still looking natural - there are no angles or sharpness. You can particularly see that at the top of the slope as compared with the TMVL20 image. The right side of the picture has not been changed and is still too steep, which is why there is still rock there (as well as a small flat area at the bottom!)If I drag the coast out even one more LOD17 quadrant, I get this:http://forums.avsim.net/user_files/149451.jpgVery nice, gently sloping ground. So, we can get either effect by just drawing a coast more carefully.Those comparison screenshots of FS 9 and 10 are fascinating, don't you think? The FS 9 terrain is very typical of the situation and you can see the rocky textures that show. That is the base LOD5 mesh that is displayed at a distance. On the other hand, FS 10 does not show the rock textures, or at least I cannot make them out. Plus the terrain is more detailed, but it does not look to be more than what we can get now, perhaps a LOD9? Although I suspect that the viewing distance has increased! At that distance, a lower resolution mesh should have taken over and it would not be possible to see so much detail from so far in FS 9.The rest of it is beautiful, though. Lots of details and the artwork is lovely! You can see the subtle variations in color and shading, very nice. Good art. Really, it would seem that the greatest impact from this version of FS will be in the artwork, Jason's domain. So, maybe his picture should be on the DVD cover!Best regards.Luis

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>Horst, where have you been? We have missed you.>>You are completely right! I forgot all about the Terrain>Maximum Vertex Level setting. I always keep it at the default>of 19 because of the problems that arise when placing it>higher. Thank you for bringing that important point up.>>Please compare the first image above of the angular and rocky>slope with the same thing at TMVL 20:>>http://forums.avsim.net/user_files/149448.jpg>>>>>It looks much better since FS is displaying more of the mesh.>It still has the rock ground textures, and on a coast this>means that the slope is too steep and that the mesh has been>flattened by the water mask.>>You can see the problem here:>>http://forums.avsim.net/user_files/149449.jpg>>>>>There are still elevation values beyond the coast. The>solution is to drag the coast beyond the LOD17 quadrant so as>to allow those elevation values to display. And here is the>result:>>http://forums.avsim.net/user_files/149450.jpg>>>>>This is with TMVL 19. There is still a little bit of rock, but>I can live with it. Also, please notice how the slope on the>left of the picture goes almost straight down to the water>while still looking natural - there are no angles or>sharpness. You can particularly see that at the top of the>slope as compared with the TMVL20 image. The right side of the>picture has not been changed and is still too steep, which is>why there is still rock there (as well as a small flat area at>the bottom!)>>If I drag the coast out even one more LOD17 quadrant, I get>this:>>http://forums.avsim.net/user_files/149451.jpg>>>>>Very nice, gently sloping ground. So, we can get either effect>by just drawing a coast more carefully.>>Those comparison screenshots of FS 9 and 10 are fascinating,>don't you think? The FS 9 terrain is very typical of the>situation and you can see the rocky textures that show. That>is the base LOD5 mesh that is displayed at a distance. >>On the other hand, FS 10 does not show the rock textures, or>at least I cannot make them out. Plus the terrain is more>detailed, but it does not look to be more than what we can get>now, perhaps a LOD9? Although I suspect that the viewing>distance has increased! At that distance, a lower resolution>mesh should have taken over and it would not be possible to>see so much detail from so far in FS 9.>>The rest of it is beautiful, though. Lots of details and the>artwork is lovely! You can see the subtle variations in color>and shading, very nice. Good art. Really, it would seem that>the greatest impact from this version of FS will be in the>artwork, Jason's domain. So, maybe his picture should be on>the DVD cover!>>Best regards.>>LuisThanks Luis. Good art is important, but IMO the biggest impact is from the amount/quality of data we are working with this time around.A couple of short replies:Yup, I was talking about terrain texture resolution as opposed to mesh resolution. Shipping resolutions are not yet set, but what you've seen is indicative of what should ship.The reason the mountains in the before and after shots don't show the gradient slope texture is because... I cheated. :)The gradient slope texture replacement, while heavy handed, is the best generic solution to extreme changes in elevation that we've come up with to date. That being said, although it's been in the product for the last couple of versions it's never gotten a lot of close visual design scrutiny. We've spent some time revamping this area, and I expect that you'll like the differences (as seen in some savannah shots and in the hawaii shot). I *think* that there'll be a mechanism by which the community will be able to dink with the mapping system, but I'm not sure of that. Cheers,Jason

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Thanks for the clarification, Jason. I was wondering about those mountains - they do look beautiful. Maybe you should cheat like that for the shipping version!The gradient slope texture is a good solution to that problem of sharp elevation changes. Sometimes it is out of place, but mostly it works very well, which is a pretty good average for solutions in general.Sorry to disagree with you, but it seems clear that no matter how much work and effort has been put into the other aspects of FS, what will "wow" everyone, particularly new users, is the art and the details that make the FS world appear so realistic. That and being able to drop sacks of flour on things!Best regards.Luis

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Hi there,interesting discussion here, as always!For the expanding-the-coastline part of the discussion: one method for automating this process for larger areas is to use AutoAsm or Slarti for the initial LWM files. Since both programs use masking files for this process it's easy enough to enlarge the water masks ("grow selection") in Photoshop or similar programs prior to sending them to Slarti. Of course, manual post-processing will usually lead to better results but that's not always an option.I definitely have a love-hate relationship with the gradient-based texture replacement. On the one hand it allows us to use it to our advantage (the low-gradient switchers, like settlements, can be transformed via local land class/texture sets to muskegs, rice paddies, or other types that are restricted to flatter areas. On the other hand, the switch to the 056 cliff textures at about 40 degrees of slope occurs too soon for most areas of the planet. Thus, in my feedback to the FS design team I always ask for increasing that upper threshold by at least 10 degrees. It looks like this may be one of the changes in FSX and it's not too surprising as the current overabundance of cliffs becomes very apparent with the use of higher-res mesh, which FSX seems to be shipping with. Cheers, Holger

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And if I can jump in about TMVL: Particularly when creating floatplane bases and harbours, or placing bridges in non-flat terrain, I find TMVL=21 to be required for improved realism, and am designing assuming that is the minimum resolution. This is tough as many folks do not want to use 21 for performance or aesthetic reasons, and I get complaints from folks with TMVL = 19 or 20 who say their bridge doesn't line up or land slopes through a gmax harbour object.With a higher max TMVL possible in FSX (say 36)(here Jon starts wild unfounded rumours)I'm not sure whether this will be better or worse. As a designer I'll have to think about whether it makes sense to demand users use the highest TMVL possible, which may reduce enjoyment for some folks.Holger will be quick to point out that he recommends folks keep a desktop link to quickly change TMVL, but I'm not sure how many people are willing to do that.Jon

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>Thanks for the clarification, Jason. I was wondering about>those mountains - they do look beautiful. Maybe you should>cheat like that for the shipping version!>>The gradient slope texture is a good solution to that problem>of sharp elevation changes. Sometimes it is out of place, but>mostly it works very well, which is a pretty good average for>solutions in general.>>Sorry to disagree with you, but it seems clear that no matter>how much work and effort has been put into the other aspects>of FS, what will "wow" everyone, particularly new users, is>the art and the details that make the FS world appear so>realistic. That and being able to drop sacks of flour on>things!>>Best regards.>>Luismaybe cheat is the wrong word... :)Those mountains are part of the new changes.Cheers,Jason

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Holger,"I definitely have a love-hate relationship with the>gradient-based texture replacement. On the one hand it allows>us to use it to our advantage (the low-gradient switchers,>like settlements, can be transformed via local land>class/texture sets to muskegs, rice paddies, or other types>that are restricted to flatter areas. On the other hand, the>switch to the 056 cliff textures at about 40 degrees of slope>occurs too soon for most areas of the planet."Yes I've always agreed. This area has been overhauled a bit. Cheers,Jason

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