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Terrain Mesh Complexity

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Guest FlyboyMichael

Hi Guys,What does the terrain mesh complexity slider do visually? Which variables does it change in the fs9.cfg file? What is the difference in setting it between 80 and 100?Thanks,

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Guest guex

Hi,As far as I know, the terrain mesh complexity slider increases or decreases the precision of the representation of the landscape (mountains, valleys, etc) in the simulator.Raising to 100 will represent the full level of detail (LOD) of the landscape under your aircraft. The backside of the medal is: the higher the setting, the higher the framerate hit...Lowering the slider to far left will let the hills pop up as you come closer.Try to find a setting according to your PC performance and your visual needs.

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Mostly effective with mesh terrain addon scenery.I also set the value TERRAIN_MAX_VERTEX_LEVEL=21

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Guest FlyboyMichael

Are you saying that the terrain mesh complexity slider does not affect how accurately the hills are reproduced, but only how close I need to get to the hills before they are accurately displayed. Do you have any feeling for how the slider value is mapped to a radius in miles.Thanks for your help,

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Guest FlyboyMichael

What does setting this variable to greater than 19 have on the default FS9 scenery?Thanks,

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Guest sgreenwood

>Are you saying that the terrain mesh complexity slider does >not affect how accurately the hills are reproduced, but only >how close I need to get to the hills before they are accurately displayed. Reducing the slider below 100% degrades the accuracy of reproduction, not the radius in which the the terrain is reproduced accurately. The algorithm used to render terrain in the sim degrades accuracy from foreground to horizon with ALL mesh, compressing many data points into fewer and fewer pixels as you move toward the horizon, where a vertical inch on the screen represents many more miles on the earth's surface than does a comparable inch at the bottom of the screen. The slider simply adds to this degradation, starting right at the bottom of the screen. Take screenshots taken in an area with good mesh, the Grand Canyon for example. Set the slider at 100%, then at 0%, to see the extreme effects of the slider. Quite a difference.>Do you have any feeling for how the slider value is mapped to a >radius in miles.It does not seem to be in FS2002.In FS2004, TERRAIN_MIN_DEM_AREA and TERRAIN_MAX_DEM_AREA are "used to calculate the DEM radius based upon the TERRAIN_ERROR_FACTOR" It is not entirely clear how these work yet, or even precisely what the terms mean, but setting TERRAIN_MAX_DEM_AREA to 200 does provide a little more detail in the distance and reducing it to less than 100 does reduce the radius of the area with the most terrain detail - a value of 50 has a very obvious effect, but may improve FPS.... I don't assume those units represent a linear radius in miles however.>I also set the value ... TERRAIN_MAX_VERTEX_LEVEL=21>What does setting this variable to greater than 19 have on the default>FS9 scenery?The higher the resolution the greater the improvement. But FPS may suffer. Maximum effective value is 21, but 20 is pretty good in FS2004.See the files below for areas covered and LOD resolutions of the FS2002 and FS2004 default mesh - some of it is pretty good.www.fs-traveler.com/cgi-bin/fs2002-default_mesh.zipwww.fs-traveler.com/cgi-bin/fs2004-default_mesh.zipHope this helps,Stevewww.fs-traveler.com

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Guest FlyboyMichael

I've tried looking in mountainous regions for differences between Terrain Mesh Detail levels of 80 and 100. I can't see any difference. Should I be able to see a difference between these levels or is the difference insignificant?Will the TERRAIN_MAX_VERTEX_LEVEL variable set to 20 or 21 cause the default mesh to look any better, or is this only for addon mesh?The TERRAIN_DEFAULT_RADIUS and TERRAIN_EXTENDED_REDIUS variable are set to 0 in the fs9.cfg file. What do these setting do?Thanks for your help,

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Guest sgreenwood

>I've tried looking in mountainous regions for differences between Terrain Mesh>Detail levels of 80 and 100. I can't see any difference. Should I be able to see >a difference between these levels or is the difference insignificant?It depends on the resolution of the mesh there. And how you fly. It is most obvious when near the ground. I probably wouldn't bother if all my time were spent flying at 30,000 ft. Screenshots may be necessary to see the difference, especially if the mesh LOD resolution is low. If screenshots are the only way to tell the difference, then you will probably be happy with a value of 80, where you may see improved FPS (although this improvement will be proportional to the resolution as well).I suggest downloading the appropriate file above to see what the resolution is for your area. It ranges from very low in some mountainous areas of the world to very high is a few.>Will the TERRAIN_MAX_VERTEX_LEVEL variable set to 20 or 21 cause the >default mesh to look any better, or is this only for addon mesh?It makes high resolution mesh look better (LOD9 and especially LOD10 or higher). There is quite a bit of default mesh in FS2004 which should benefit from the higher value, although it may not be in areas of interest to you. The files above will help you locate a good test area where you can try different values and decide for yourself. Again, no magic bullet, but I always have mine set at 21.I also have a brief note of the topic at:www.fs-traveler.com/tmv-example.html>The TERRAIN_DEFAULT_RADIUS and TERRAIN_EXTENDED_REDIUS variable are set to 0 in the >fs9.cfg file. What do these setting do?Hardware capability and settings may affect how well you can see the differences in settings. See the posts by Kurt in this thread. He has a set of files you can download to test them yourself, and some recommended settings for FS2002 and FS2004. Quite technical, but worth saving for reference:terrain settingsExcerpt (edtited):=====================all of these settings give equal results in FS2004Listed in this order, TERRAIN_DEFAULT_RADIUSTERRAIN_EXTENDED_RADIUSTERRAIN_EXTENDED_LEVELS4.0 0.0 04.0 4.0 14.0 4.0 xxxxxxx10.0 16.0 49.5 4.0 xxxxxxx9.5 4.0 0 thru 4======================Steve

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Guest FlyboyMichael

Thanks for your detailed reply.I guess I have a lot of experimenting to do.

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Guest product

I intentionally fly in flatter areas, while seeing mountains in the distance is nice it can really eat up smoothness. Florida has some advantages!Joel

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Guest JonP01

The strange thing about this setting in FS2004 is that on my particular machine, it does not do the same thing that it did in FS2002 (I am comparing the stock out of the box programs here).In FS2002, as people said, it would reduce the resolution of the terrain features, sometimes to the point where terrain features would almost disappear. At the very best, it made terrain features "pop" in or out if the slider was set anywhere below about 90 - 95%.In FS2004, the terrain mesh resolution seems much less effected by moving the slider. Even the difference between 100% and 0% in FS2004 is much less than the difference between 100% and 80% was in FS2002. In fact on my system the slider seems to effect the landclass detail more than the mesh resolution. In screenshots I've taken, I can't tell the difference in the terrain betweem 0% and 100%, but the textures used at 100% are far more varied. Also, even if I set the slider at 0% in FS2004, there is no texture popping at all - something that would start happening in FS2002 at 94% and below.

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Guest product

I didn't kow that the mesh slider affected landclass, are you sure about that?Joel

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Guest

It affects ONLY scenery on the horizon, not anywhere where you'd see the details anyway.I have had it turned to 0 for a long time, and there's hardly a difference with 100. Only thing you see is that smaller hills and mountains out to 60+nm are not clearly defined, which is OK as you'd not see them anyway in most weather in most of the world at that distance.

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Guest sgreenwood

Mine too, so I did some more detailed testing today and have a bit more information about the roles of TERRAIN_ERROR_FACTOR (terrain mesh complexity slider), TERRAIN_MIN_DEM_AREA, and TERRAIN_MAX_DEM_AREA in FS2004. This is not the last word on the subject, but will hopefully help others focus their testing in productive directions.* The effects of changes in settings for TERRAIN_ERROR_FACTOR are much more subtle in this version.* I have also seen the changes in textures with change in TERRAIN_ERROR_FACTOR valus previously, but not today - perhaps due to different testing conditions (20,000ft over mountain range in Alaska, 60m mesh today). I thought they may be due to the changes in textures we see when the slope changes, not a difference in landclass. It did make it difficult to decide exactly what was changing.* The big change in the role of TERRAIN_ERROR_FACTOR is the fact that its behavior is controlled by the values of TERRAIN_MIN_DEM_AREA and TERRAIN_MAX_DEM_AREA, although the details of the interactions are not clear. If either of these parameters is set to 200, then the TERRAIN_ERROR_FACTOR setting seems to have no effect at all; from 0 to 100%, the terrain is the same. (200 seems to be the maximum value which has any effect - this is as good as the terrain gets.) The default TERRAIN_MAX_DEM_AREA value of 100 is close to this, which is why little effect has been reported so far.A few test results, with all other settings constant. If there are interactions with other variables as well, they are not included here:If TERRAIN_MIN_DEM_AREA=0 and TERRAIN_MAX_DEM_AREA=15, changes in TERRAIN_ERROR_FACTOR do affect the terrain, from the foreground out.If TERRAIN_MIN_DEM_AREA=0 and TERRAIN_MAX_DEM_AREA is set to increasing values, with TERRAIN_ERROR_FACTOR held constant, the terrain detail is changed.When TERRAIN_MIN_DEM_AREA is greater than TERRAIN_MAX_DEM_AREA, adjusting the settings within reasonable ranges does affect the terrain, but the relationships here are not obvious.* The default values are pretty good. To accomplish much more in the way of tuning will require adjusting all three parameters.I do not know how these settings influence performance, but I do not think reducing the TERRAIN_ERROR_FACTOR setting will provide as much relief in FS2004. Perhaps reducing TERRAIN_MIN_DEM_AREA and TERRAIN_MAX_DEM_AREA values below their defaults will help. Steve

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