Board index FlightGear Release candidates

FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Release candidate testers are encouraged to post their feedback here. Please read the introduction topic for details.
Forum rules
Please read the introduction topic for details.

FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby rogerx » Wed Oct 14, 2015 1:38 am

Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz
NVIDIA GeForce GTX 670 (Driver Version 355.11)
Tons of Memory

1) All set to active: Sync to VBlank, Allow Flipping, Image Settings "Mid Range Scale set to - Quality", Use Conformant Texture Clamping.
2) Override application settings: AA set to 16x, about mid range on the scale. (Similar results when using FXAA.)
3) Override application settings: Anisotropic 16x (Anisotropic at 1x had slow frame rates here! Maybe something to do with the NVIDIA Powermizer option?)

Getting around 40 FPS looking around airports and anywhere from 60-150FPS whether scenery or sea.

Only problem, VSync is active, even via command line ( $ __GL_SYNC_TO_VBLANK=1 fgfs), however FPS within flightgear is still reporting higher or greater than 60 FPS!

Overall seems better than previous versions, but likely somehow need to verify and make sure VSYNC is active by maybe browsing internal properties? Or is VSYNC to be assumed activated and just ignore FPS rates printed on screen?
(Just finished packaging for Gentoo, and compiled using standard stable O2 CFLAGS.)

I'm still seeing some graphics anomalies while looking around, or image tearing. Still leads me to believe VSYNC is not active. (If the monitor/display only has a 60 vertical refresh rate, probably wasting CPU/GPU usage rendering anything more than 60 FPS!)

CONCERNS
1) How to verify VSYNC is enabled, restricting frame rates to 60 fps
2) Frame rates seem to increase, after toggling 3D console off, and then again turning the 3D console back on. First it appears the gauges consume 10-20 FPS, but after toggling the 3D console off and noticing the increase and again toggling the 3D console active again, I can see the gauges appear to consume less frame rates than when initially taking off from the airport and flying over the open sea. Odd. Maybe something with the updating of the gauges? Then again, might be nothing and all is normal.
rogerx
 
Posts: 65
Joined: Sun Jan 08, 2012 9:39 am
Location: Conneaut, Ohio

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby Thorsten » Wed Oct 14, 2015 5:54 am

While FG has an option to throttle frame rate to a certain value, aiming for 60 fps vsync (or 30 fps if that can't be achieved) is usually something the GPU driver should perform (or, in the case of my GeForce 670M, does in fact perform).
Thorsten
 
Posts: 11111
Joined: Mon Nov 02, 2009 8:33 am

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby Hooray » Wed Oct 14, 2015 10:07 am

and it is in fact a setting exposed by the driver, too:
http://wiki.flightgear.org/Troubleshoot ... up_profile
Image
Please don't send support requests by PM, instead post your questions on the forum so that all users can contribute and benefit
Thanks & all the best,
Hooray
Help write next month's newsletter !
pui2canvas | MapStructure | Canvas Development | Programming resources
Hooray
 
Posts: 11354
Joined: Tue Mar 25, 2008 8:40 am

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby rogerx » Wed Oct 14, 2015 2:35 pm

I know about the VSYNC option within the NVIDIA settings panel, however VSYNC within the settings panel is already activated or set to "on". And yet frame rates within flightgear are still being reported above 60 fps. (ie 150 fps)

Within Windows when the NVIDIA driver vsync option is enabled; from my memory, other applications would not report frame rates above 60 fps, except for maybe intermittent 61-65 fps.

Within flightgear, (for the record within this thread here...) the application vsync option looks to be around here:

--prop:/sim/rendering/vsync-enable=true
--prop:/sim/frame-rate-throttle-hz=60

Reading more into some Rembrant posted research by accident, I should also note I've also disabled most of the angle views, all except for First Person and Model view.

Comparing the frame rate stutter or tearing seems to be similar to some other Windows' applications, however very apparently more gracefully handled. Either the NVIDIA driver vsync is not working as it should here, or flightgear is reporting possible frame rate without regard to vsync. Shrugs, just guessing as I haven't read the code!
rogerx
 
Posts: 65
Joined: Sun Jan 08, 2012 9:39 am
Location: Conneaut, Ohio

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby MIG29pilot » Wed Oct 14, 2015 2:45 pm

rogerx wrote in Wed Oct 14, 2015 1:38 am:Getting around 40 FPS looking around airports and anywhere from 60-150FPS whether scenery or sea.


Oh please don't tease.
User avatar
MIG29pilot
 
Posts: 1454
Joined: Tue May 19, 2015 4:03 pm
Location: 6 feet under Snow
Callsign: MIG29pilot
Version: 3.7nightly
OS: Windows 10

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby Hooray » Wed Oct 14, 2015 2:50 pm

the driver is generally responsible for this stuff, and it can only be overridden using flags/environment variables that you need to explicitly set. Otherwise, FG does not do anything fancy with vsync. All the relevant settings, you seem to have found already.
So, I would suggest to check some other OpenGL/OSG apps next, e.g. fgviewer/osgviewer or any of the osg demos.
Alternatively, consider running an OpenGL benchmark to see what that is reporting.
Please don't send support requests by PM, instead post your questions on the forum so that all users can contribute and benefit
Thanks & all the best,
Hooray
Help write next month's newsletter !
pui2canvas | MapStructure | Canvas Development | Programming resources
Hooray
 
Posts: 11354
Joined: Tue Mar 25, 2008 8:40 am

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby rogerx » Wed Oct 14, 2015 3:38 pm

Bingo. I am now seeing frame rates being limited to 60 fps. I'm also now seeing roughly equivalent performance to one other Windows' applications I frequently use when compared to using Linux here for this discussion.

Maybe yesterday I enabled vysnc within NVIDIA settings, of which required Xorg restarting, or maybe even the NVIDIA driver to reload -- but likely just Xorg restarting solved this.

(For those whom think I'm teasing, remember to also turn off "AI" > "Traffic and Scenario Settings" > "Disable AI"! Else AI traffic will literally eat your CPU resources. Viewing around airports tends to also significantly drop frame rates. Also try intermittently switching off the cockpit instruments using the 'c' key while looking at the sea or only rural areas.)

For this discussions record, users can further script the above options into a file for easier start-up. I've added a few commented lines for further possibilities.

--- Snip: /home/roger/bin/fgfs.sh ---
#FG_SCENERY="/usr/share/games/flightgear/Scenery"
#gdb --args /usr/games/bin/fgfs \
export __GL_SYNC_TO_VBLANK=1
#export __GL_FSAA_MODE=10
/usr/games/bin/fgfs \
--aircraft=c172p \
--disable-ai-traffic \
--browser-app=/usr/bin/seamonkey \
--callsign=rogerx \
--disable-terrasync \
--timeofday=noon \
--fg-root=/usr/share/games/flightgear/ \
--prop:/sim/hud/draw-fps=1 \
--units-feet \
--prop:/sim/rendering/multithreading-mode=AutomaticSelection \
--prop:/sim/rendering/shaders/quality-level=0 \
--prop:/sim/rendering/texture-compression=off \
--prop:/sim/rendering/vsync-enable=false \
--prop:/sim/frame-rate-throttle-hz=60 \
--log-level=alert
--- Snip ---

I've heard setting VSYNC on within the driver, and VSYNC off within the application is optimal, but could be just wishful thinking. There's a few other lines concerning optimizations, but those might not be needed anymore within FlightGear 3.6.0.
rogerx
 
Posts: 65
Joined: Sun Jan 08, 2012 9:39 am
Location: Conneaut, Ohio

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby wkitty42 » Wed Oct 14, 2015 3:52 pm

MIG29pilot wrote in Wed Oct 14, 2015 2:45 pm:
rogerx wrote in Wed Oct 14, 2015 1:38 am:Getting around 40 FPS looking around airports and anywhere from 60-150FPS whether scenery or sea.


Oh please don't tease.

i can honestly say that the video card is a huge factor in the frame rates... i've been running a NVIDIA GeForce 8400GS [GT218] card and getting ~5 to 8 fps at 1280x1024 resolution... that card was like $30US at Christmas 2014... we just went and got a NVIDIA GeForce GT730... the difference is astounding... now i see an average of 25 to 30 fps and in some cases upwards of 40+ fps... the new card has 384 GPUs... i'm not sure what the old card had but i believe maybe 4 GPUs due to the configuration being 256M per GPU and there is 1G of ram on the old card... the new card also has 1G of ram but the number of GPUs is the real difference... i got the 730 for $60US at BestBuy... if they had had the GT750 in stock at the store, i would have spent $65US instead... the 750 has 512 GPUs and would given even more fps... 128 additional GPUs for $5US? heck yeah! but i needed the card immediately and didn't have days to wait for it to be shipped...

my point? if you can swing purchasing a new video card, it can make all the difference in the world... just make sure what kind of slots your desktop machine has before you go looking and spending money on the wrong thing... make sure your monitor will also be able to connect to the card... there's nothing like the letdown of having a 15-pin VGA monitor and getting a card that only does DVI or HDMI and comes without an adapter cable...
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
User avatar
wkitty42
 
Posts: 5700
Joined: Fri Feb 20, 2015 3:46 pm
Location: central NC, USA
Callsign: wk42
Version: git next
OS: Kubuntu 14.04.5

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby rogerx » Wed Oct 14, 2015 4:47 pm

Ditto concerning video card quality. Also with NVIDIA model numbers, avoid buying lower second digit model numbers, as those models tend to have fewer CUDA cores. (This is mentioned within one of the many flightgear WIKI pages related to video cards, and I could be slightly incorrect as I'm just reiterating what I can recall.)

Concerning my --prop line mentioned above, I'm seeing many of those options not listed currently within the 3.6.0 property browser. One or two are duplicates of what is already defaults for flightgear 3.6.0.

And further BINGO! I've heard of setting bit depth lower than the default video card default setting can negatively effect rendering performance, and this looks to be the issue with almost all my frame rate settings.

Setting View > Rendering Options > Shader Effects from Performance (default) setting to Quality setting, I can see frame rates bounce from the low 30's when looking at anything outside the aircraft window at the airport, to up to 60 fps!

I think flightgear has a bottleneck problem/bug someplace within a pipeline someplace. Too many frame rates, and frame rates significantly drop. This is only evident when setting the Quality of Shaders slider from Performance to Quality, with likely your NVIDIA GTX 670 cards. Cheers! Only sometimes now do FPS drop to 30-40 when intermittently looking at the airport from inside the aircraft, but model view FPS looks great.

IN BRIEF:
How do these changes to the Video Card Trouble Shooting page sound?
1) If you have a high end system (ie. i7-3770K with NVIDIA GTX 670), then try increasing "Setting View" > "Rendering Options"> "Shader Effects" from Performance (default) setting to Quality setting. (Too low of a setting causes a bottleneck somewhere?)
2) VSYNC not enabling within the driver setting (ie. NVIDIA Settings), try restarting Xorg after saving the setting to the configuration file. (Maybe even reloading the driver with the VSYNC option enabled?)
Last edited by rogerx on Wed Oct 14, 2015 5:00 pm, edited 1 time in total.
rogerx
 
Posts: 65
Joined: Sun Jan 08, 2012 9:39 am
Location: Conneaut, Ohio

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby Thorsten » Wed Oct 14, 2015 4:52 pm

I think flightgear has a bottleneck problem/bug someplace within a pipeline someplace. Too many frame rates, and frame rates significantly drop.


That last sentence doesn't make a lot of sense.

In general, I would advise you to not post speculations on what causes the framerates you observe unless you have pretty solid test data and the context knowledge to interpret it - there are people in the forum who actually know these things really well.
Thorsten
 
Posts: 11111
Joined: Mon Nov 02, 2009 8:33 am

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby wkitty42 » Wed Oct 14, 2015 5:06 pm

rogerx wrote in Wed Oct 14, 2015 4:47 pm:Ditto concerning video card quality. Also with NVIDIA model numbers, avoid buying lower second digit model numbers, as those models tend to have fewer CUDA cores. (This is mentioned within one of the many flightgear WIKI pages related to video cards, and I could be slightly incorrect as I'm just reiterating what I can recall.)

that is exactly the reason why i went for the 730 and wanted the 750... that middle digit... i wasn't really concerned with the first or third digit because i've not heard what they are all about...

rogerx wrote in Wed Oct 14, 2015 4:47 pm:Concerning my --prop line mentioned above, I'm seeing many of those options not listed currently within the 3.6.0 property browser. One or two are duplicates of what is already defaults for flightgear 3.6.0.

i have several property settings related to the video and rendering set as well... i forget where i picked them up but i think they helped with that 213 card i was using... i'm not sure now, though, as i've run into a bit of an oops when i thought i was commenting them out but they were still being parsed :lol: hopefully that will be taken care of soon so that i don't have to completely remove them from where i have them entered and so that i don't have to start keeping multiple "save" files with various settings in them to paste in when desired :)

rogerx wrote in Wed Oct 14, 2015 4:47 pm:And further BINGO! I've heard of setting bit depth lower than the default video card default setting can negatively effect rendering performance, and this looks to be the issue with almost all my frame rate settings.

i think i've set and kept mine at 32bpp "for ever"... something keeps telling me that 24 bit is optimum, though... i think that's coming from some programming graphics discussions from another place long long ago...

rogerx wrote in Wed Oct 14, 2015 4:47 pm:Setting View > Rendering Options > Shader Effects from Performance (default) setting to Quality setting, I can see frame rates bounce from the low 30's when looking at anything outside the aircraft window at the airport, to up to 60 fps!

another consideration in this aspect is your LOD settings...

rogerx wrote in Wed Oct 14, 2015 4:47 pm:I think flightgear has a bottleneck problem/bug someplace within a pipeline someplace. Too many frame rates, and frame rates significantly drop. This is only evident when setting the Quality of Shaders slider from Performance to Quality, with likely your NVIDIA GTX 670 cards. Cheers! Only sometimes now do FPS drop to 30-40 when intermittently looking at the airport from inside the aircraft, but model view FPS looks great.

there is quite a bit to consider when it comes to graphics rendering... that's for sure!
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
User avatar
wkitty42
 
Posts: 5700
Joined: Fri Feb 20, 2015 3:46 pm
Location: central NC, USA
Callsign: wk42
Version: git next
OS: Kubuntu 14.04.5

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby rogerx » Wed Oct 14, 2015 5:09 pm

Thorsten: "In general, I would advise you to not post speculations on what causes the framerates you observe unless you have pretty solid test data ..."

What? I just reproduced this here. About the only item I have not performed, is a kernel reboot, or system cold start. I'd suggest you reread my posts or logging here, and then retry on your platform to see if you can reproduce. If you think low-level, this scenario is not unheard of at all.

Furthermore, I would never advise telling people to not post what they merrily think, unless those comments were considered defamatory. Even then, I usually simply ignore them. ;-)

Ditto wkitty42. Quite a bit to graphics, low-level coding is much easier!

TODO: Reinstall FlightGear-3.4.0 to see if I can further reproduce what I'm seeing with 3.6.0
rogerx
 
Posts: 65
Joined: Sun Jan 08, 2012 9:39 am
Location: Conneaut, Ohio

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby MIG29pilot » Wed Oct 14, 2015 6:33 pm

rogerx wrote in Wed Oct 14, 2015 3:38 pm:(For those whom think I'm teasing, remember to also turn off "AI" > "Traffic and Scenario Settings" > "Disable AI"! Else AI traffic will literally eat your CPU resources. Viewing around airports tends to also significantly drop frame rates. Also try intermittently switching off the cockpit instruments using the 'c' key while looking at the sea or only rural areas.)


About the only way for me to get 40 fps would be to stare at the sky with the ufo and all shaders, effects, and features off, no ALS, no clouds, no multiplayer, no scenery, no models, no nothing.
User avatar
MIG29pilot
 
Posts: 1454
Joined: Tue May 19, 2015 4:03 pm
Location: 6 feet under Snow
Callsign: MIG29pilot
Version: 3.7nightly
OS: Windows 10

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby legoboyvdlp » Wed Oct 14, 2015 6:37 pm

The only way for me to get 53FPS is to start with minimal profile.
Yes, my GPU is an integrated laptop one :|
User avatar
legoboyvdlp
 
Posts: 7111
Joined: Sat Jul 26, 2014 1:28 am
Callsign: YV-LEGO
Version: 2018.3.1
OS: Windows 10 HP

Re: FlightGear 3.6.0 RC Frame Rate and Graphics Experience

Postby Thorsten » Thu Oct 15, 2015 6:27 am

What? I just reproduced this here. About the only item I have not performed, is a kernel reboot, or system cold start. I'd suggest you reread my posts or logging here, and then retry on your platform to see if you can reproduce. If you think low-level, this scenario is not unheard of at all.


First, because 'too many framerates' implies high framerate, so to continue the sentence with 'and frame rates significantly drop' makes no sense, because the whole sentence then says 'when I have high framerates, I have low framerates'.

Second, you haven't posted anything reproducible. For meaningful benchmarking tests we need at least aircraft, location, LOD settings, rendering settings, visibility, weather settings,... Also, for a few comments on meaningful benchmarks, see here.

Furthermore, I would never advise telling people to not post what they merrily think, unless those comments were considered defamatory. Even then, I usually simply ignore them. ;-)


Well, that's your problem on the horizon.

You can of course post whatever you want, but if you want the right people to read it, what you say has to have sufficient information content. Do you for instance know what internally happens when you move the quality slider? I think not, otherwise you would have known that the detailed setting is crucial information and included it in every report.

I'm not interested at all in discussing idle speculations on how FG rendering might be done and what problems might be - I contributed a significant share to it and know its pitfalls reasonably well - I prefer to spend my time helping out people who actually want to understand something. As I said elsewhere. there's no shortage of people who feel they must tell everyone how rendering 'really' works. Given that, there is however a strange shortage of people who come up with fast and visually appealing rendering code.
Thorsten
 
Posts: 11111
Joined: Mon Nov 02, 2009 8:33 am

Next

Return to Release candidates

Who is online

Users browsing this forum: No registered users and 1 guest