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styckx

Tessellation

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I saw people talk about it, explain it, define it, and I've seen people maxing it out.

 

What  I've yet to see someone show exactly what it does in game. I always knew what it was as many games use it now a days..

 

Before and after Low Vs Ultra

 

WARNING - 2.31MB / 1904x1002 animated GIF

 

http://farm8.staticflickr.com/7430/11397243743_c8b3031af7_o.gif

 

Enjoy!

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Thank you. This is exactly what I was looking for. The difference is very noticeable and enhancement by Ultra to the terrain mesh looks very nice.

 

On my computer I hardly see any performance difference between low and ultra, so I guess that I'll just stick with tessellation Ultra.

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Excellent - thanks for that Bill. How's the performance difference on your machine between the two settings?

 

I was getting some scenery spikes at ultra on my 680 (but that was early days when I was still throwing everything and the kitchen sink into P3D). Might be worth a re-try...

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Haven't tested that.. But...  Eyeballing it.. No.. I don't notice much if any of a difference but I've honestly not actually flown with in it set to ultra because it's useless where I fly right now.(flat-lander!. :)  You can see, once you get past the main features of Rainier the enhancement it adds isn't very dramatic so I've just kept it low because I honestly don't know the performance impact and siding with low till I know otherwise. :)

 

It just dawned on me.. Tessellation = Mesh Complexity in FSX renamed.. I've been dialog trolled! 

 

Holy cow time for bed..  Or.... Make coffee.....  ^_^

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Haven't tested that.. But...  Eyeballing it.. No.. I don't notice much if any of a difference but I've honestly not actually flown with in it set to ultra because it's useless where I fly right now.(flat-lander!. :)  You can see, once you get past the main features of Rainier the enhancement it adds isn't very dramatic so I've just kept it low because I honestly don't know the performance impact and siding with low till I know otherwise. :)

 

It just dawned on me.. Tessellation = Mesh Complexity in FSX renamed.. I've been dialog trolled! 

 

Holy cow time for bed..  Or.... Make coffee.....  ^_^

 

Close but not quite. From what I can tell, FSX is not doing additional subdivisions, but simply skipping over vertices as you reduce mesh complexity. Hardware tessellation in P3D v2 allows you to procedurally increase resolution using the GPU through subdivision algorithms. Do that on the CPU and things become much slower.

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Close but not quite. From what I can tell, FSX is not doing additional subdivisions, but simply skipping over vertices as you reduce mesh complexity. Hardware tessellation in P3D v2 allows you to procedurally increase resolution using the GPU through subdivision algorithms. Do that on the CPU and things become much slower.

 

Gotcha.. Thank you for the more technical answer.  We're all sorta learning here..  B)

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Gotcha.. Thank you for the more technical answer. We're all sorta learning here.. B)

I kind understand what tessellation is doing. The question is, for me at least, is that better looking detail actually accurate or is it made up of a calculated and contrived version of vertices that were not there in the original?

 

Chas

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I kind understand what tessellation is doing. The question is, for me at least, is that better looking detail actually accurate or is it made up of a calculated and contrived version of vertices that were not there in the original?

 

Chas

 

I think it still conforms to the installed mesh: it's just another method/tech of getting things done.

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I saw people talk about it, explain it, define it, and I've seen people maxing it out.

 

What  I've yet to see someone show exactly what it does in game. I always knew what it was as many games use it now a days..

 

Before and after Low Vs Ultra

 

WARNING - 2.31MB / 1904x1002 animated GIF

 

http://farm8.staticflickr.com/7430/11397243743_c8b3031af7_o.gif

 

Enjoy!

That's a pretty conservative use of tessellation it seems, so I'm not surprised there is not that big a FPS hit. I'm going to suspect its probably being more heavily used in the water effects.....

 

An example of what tessellation can do.

 

 

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Close but not quite. From what I can tell, FSX is not doing additional subdivisions, but simply skipping over vertices as you reduce mesh complexity. Hardware tessellation in P3D v2 allows you to procedurally increase resolution using the GPU through subdivision algorithms. Do that on the CPU and things become much slower.

 

Is this still the case if you don't have hardware tesselation ticked? The tesselation factor slider is still there whichever is selected.

 

I'm currently running without hardware tesselation as I prefer the 'baked in' scenery shadows to the currently broken (and not far extending) dynamic scenery shadows. The rest of the shadows I can live without.

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Do you get a performance gain going to low from ultra?

 

I get a performance gain using tesselation at higher settings than low - as long as GPU usage or memory is not already maxed out at 100% before that by lighting or shadows etc. This should be the case with most newer GPU's unless you have a 1 gb card and its already maxed before turning anything up. Turning this off can actually rob you of performance and you loose pushing the geometry to the GPU forcing it to the CPU. 

 

You need to throw conventional wisdom about tweaking FSX out the window it's a whole new ballgame. You need to tweak settings while watching both GPU and CPU usage.

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huh - you don't say. I've really got to give this a try when I get home...

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Is this still the case if you don't have hardware tesselation ticked? The tesselation factor slider is still there whichever is selected.

 

I'm currently running without hardware tesselation as I prefer the 'baked in' scenery shadows to the currently broken (and not far extending) dynamic scenery shadows. The rest of the shadows I can live without.

 

From what I can tell, without tessellation the mesh complexity is just hard set at what 100% would of been in FSX. 

 

So what tessellation is doing is indeed above and beyond what FSX was doing.

 

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Although short, this turned out to be more informative than I imagined.. Awesome thread! 

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I ran some benchmarks moving from high to ultra. No change in FPS or VRAM on my 780, but I also could not tell any difference in visuals, so I'll probably keep my setting at high.

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but I also could not tell any difference in visuals

 

I could see an obvious difference between the various settings. Apart from the obvious (mountains) I also noticed a difference in Norway on slopes that ran into the water: with a low setting they looked odd (in the distance) as if something went wrong with the texture and with the higher settings things looked okay. The setting apparently not only has to do with the quality but also with the distance at which certain things are rendered. 

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Interesting to see because it does really made a big difference.

Thanks for taking the time Bill.

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I have a 3ghz I7-950 X58 system that at one time I use to run Prepar3d quite happily on a SSD raid.  I took a hiatus, backed it up and then deleted the install.  Coming back a few years later I decided to do a fresh install, this time however on a HDD Raid.  I have been struggling with abysmal performance for the past two weeks and have tried damn near every possible tweak with the exception of one, Tessellation at Ultra.  This is just not the ultra system although with a GTX970 this is the one setting that should be Ultra.  The difference in performance is night and day.  I couldn't even use an affinity mask on this system, ALL 8 cores were needed to keep up. I use Processor Lasso and tried several configs, all but 0, only physical...not enough go juice.  Before tessellation I was looking at locking this system at 20fps since that's all the cpu could manage on average and terrain loading was just awful with stutters so long you could eat dinner even at that FPS with all 8 cores maxed.  Scenery settings were all normal, 4.5 LOD ,10m and 15cm, nothing in the extreme here.  I had much higher settings before and it was smooth, it was boggling.

With tessellation at ultra I can lock 30FPS now and actual move LOD and Scenery settings even higher, settings I remember having. Can cruise the F22 at 700kts in both medium and low level and mostly keep up, not quite but then I really only need 400knts max for most of my stable.  If you have an under powered CPU and a decent GPU this setting is a life saver!

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On 1/3/2017 at 2:02 AM, AoA said:

I have a 3ghz I7-950 X58 system that at one time I use to run Prepar3d quite happily on a SSD raid.  I took a hiatus, backed it up and then deleted the install.  Coming back a few years later I decided to do a fresh install, this time however on a HDD Raid.  I have been struggling with abysmal performance for the past two weeks and have tried damn near every possible tweak with the exception of one, Tessellation at Ultra.  This is just not the ultra system although with a GTX970 this is the one setting that should be Ultra.  The difference in performance is night and day.  I couldn't even use an affinity mask on this system, ALL 8 cores were needed to keep up. I use Processor Lasso and tried several configs, all but 0, only physical...not enough go juice.  Before tessellation I was looking at locking this system at 20fps since that's all the cpu could manage on average and terrain loading was just awful with stutters so long you could eat dinner even at that FPS with all 8 cores maxed.  Scenery settings were all normal, 4.5 LOD ,10m and 15cm, nothing in the extreme here.  I had much higher settings before and it was smooth, it was boggling.

With tessellation at ultra I can lock 30FPS now and actual move LOD and Scenery settings even higher, settings I remember having. Can cruise the F22 at 700kts in both medium and low level and mostly keep up, not quite but then I really only need 400knts max for most of my stable.  If you have an under powered CPU and a decent GPU this setting is a life saver!

+1 i agree , Discovered it my self a couple of month ago.

i could not figure out why i had so much blurry terrain until i saw i had turned tesselation to off or low.

 

With SLI it has to be at ULTRA and it was a changer moving some work from CPU to the GPU´s

 

Michael Moe

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