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Brian Doney

Dusk/Night/Dawn FPS hit

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I can't really say this is specific to 2.2, so maybe someone else can say...has there always been such a huge FPS penalty during dusk/night/dawn ?

 

m14e.png

 

8n9z.png

 

No AI, no addon scenery (at all), no shadows (at all), no cfg tweaks.

 

Just seems a bit much ? Not that I'm worried about maintaining 100 FPS, I just like to know how much headroom I have, and during these times I'd say not much.

 

Can't say I remember such a penalty in previous versions, but I also can't recall specifically testing for it either.

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Yeah I'm not sure what the deal is here, but I'm losing ~50 FPS just changing from day to night. 

 

I really hope this is something on my end.  :mellow:

 

Although I know they cannot be compared directly, from FSX:

 

a0bo.png

 

7xmq.png

 

Quite a drop there too, but to be fair, the 174 was a bit of an outlier with the average closer to 140 or so.

 

Having said that, I'm having a very difficult time seeing any real improvement looking at the first set of shots, and even setting that aside, ~40 fps in the default BE58 with literally nothing else going on isn't going to work.

 

Still trying to figure out what's up here.

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Please pardon the conversation I am having with myself  :lol:

 

Also pardon the extremely low settings in the next two shots. I cranked down everything trying to find the cause.

 

It seems the issue is with the particle effects used for taxiway lighting. Likely the runway lighting too, but they don't LOD out like the taxiway lighting does so it's hard to test.

 

This first shot you can see the blue edge lighting in the lower part of the shot:

 

7qq2.png

 

...and in this next shot I have slewed upwards just slightly, until they disappear:

 

flfu.png

 

So...yeah I don't know. It would be one thing if these specific lighting effects were better in P3D than FSX, but they aren't, and exact a huge penalty.

 

Here's hoping this issue is specific to my install.

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Interesting. From your first set of screenshots, I would guess it's the runway/taxiway lighting.

 

Do you have any add-on airports with custom lights? It could be a problem with those default lights specifically.

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It is absolutely the edge/center lighting, no doubt about it, and this was a vanilla install, patched, and I've since downloaded the full installer and seen the same results.

 

I guess either no one else is seeing this, or can't be bothered to check.  :unknw:

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I guess either no one else is seeing this, or can't be bothered to check. :unknw:

 

I just checked, as I have noticed lower fps after changing the time of day, but didn't take a great deal of notice..... However, I just loaded a saved flight over NCA with no visible lights, runway or otherwise, somewhere near Mt. Shasta, and used the TOD slider to advance the time... at certain points around dusk the frame rate plummets by 50% or more.  If I apply that time it remains low, so there is something odd going on here.

 

If I advance it on further it goes up again, but is still lower than day time... so yeah  :unknw:

 

At certain times... and I'll come back with those exact times to compare, it is dropping me to sub twenty frame rates.

 

EDIT:  Okay, time of day with lowest fps... Date 15/07 'Summer' .... Time 20/13/15 'Dusk'

 

EDIT2... like your taxiway lighting it seems certain lighting effects are causing my dip.. and I think it might be the suns flare effect as my position also makes a difference... need to look further.

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Try and use FRAPS to check FPS as they give a more accurate report of FPS. 

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Sorry Brian, this might be totally unrelated to your drops, and I don't wish to kidnap but, having played around some more I can get a 100% repeatable and massive drop in frame rate when either the sun or the moon is sitting on the horizon, and I look directly at it.... once it is slightly higher in the sky the frame rate is normal :unknw:

 

I disabled the flare effect, so its not that... weather has an impact, but it happens with clear weather and Vol fog turned off.

 

 

Can someone also check this please?

 

Pics.

 

From 60fps (v-sync)

 

Nv8X.jpg

 

To 38 with the sun lower... same with the moon.

0Nmna.jpg

 

 

 

 

 

 

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Sure, be glad to.

 

Would you mind repeating the last set of shots I posted at ORD ? Simply go there at night, and slew up/down right around 2500 AGL (the point where the taxi lights are removed) and see what you get.


EDIT: Can't say I see anything related directly to the sun, I actually get the feeling what you are seeing IS related to what I see.

 

The fourth shot is immediately after the default airfield lighting is switched off (KPIT is right behind me):

 

lnwp.png

 

27u0.png

 

73ld.png

 

fk0m.png

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Interesting... the sun/moon position may be coincidental then.

 

I was just trying to run the flight at KORD and P3D crashed on me :unsure:   ... I need to go out now, but will have another go later.

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Try and use FRAPS to check FPS as they give a more accurate report of FPS. 

 

I understand what you mean, but I'm pretty sure this isn't an issue with the FPS counter, as the FPS drop can definitely be felt.

 

Before wiping clean and using the full installer, I tested again at ORD with pure FSX compatible AI traffic at 10% density and the Airbus Extended, and FPS dropped into the 20s. In the last 4 shots above, you can see that PIT is a bit better which makes perfect sense, but the penalty is still significant.

 

That's really where my concern lies. I obviously have no interest in maintaining 100+ FPS, but it is a bit alarming to see so little headroom for addons. Now there aren't too many airports that are as taxiway dense as ORD, maybe DFW, CDG, AMS et al, so it isn't the end of the world, but as a tube jockey, based at ORD  :lol:, having to avoid those places from dusk until dawn would be unfortunate.

 

As of now, leaving out using settings that are beyond the reach of my hardware, the taxiway lighting is by far the largest single perf hit that I get in this sim. From 100 FPS to 40 FPS at ORD just sitting on the runway with nothing else happening.

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A few more shots, this time testing the impact of the default runway lighting.

 

Sill at ORD, looking west to avoid any potential impact from downtown Chicago, I have slewed back (east) from the 28R start position just until the runway lights disappear:

 

*FPS in this capture is actually on the low end of the avg, but good enough to make the point.

 

ozpz.png

 

Now slewing back towards ORD until the lights pop in:

 

kfex.png

 

Quite a large perimeter would need to be maintained around large facilities like ORD to avoid a huge perf penalty, and even in doing so, it sure seems a shame, with all of the wonderful visual improvements that could use this performance, to have it used up by a feature that looks no better than it's FSX counterpart.

 

I have posted over at LM with a few shots and a link to this thread. I certainly hope this is still either a configuration issue on my end, or something that can be improved by LM.

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Brian, I can repeat the fps drop with the blue egde lighting, the transition point when slewing up and down is about a 25% drop or increase when those light go on or off... I turned agn off for the test.


 

I still think those huge drops I found earlier stem from the sun/moon on the horizon, or maybe a combination of the two [both sun position and the lighting], as the drop is much bigger than then... some 50%


 

Need to do more testing, but there does seem to be an anomaly here.

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Have you posted your findings in the Prepar3D forums yet? It's best if they're aware of that problem so they can start investigating too.

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Have you posted your findings in the Prepar3D forums yet? It's best if they're aware of that problem so they can start investigating too.

 

 

 

I have posted over at LM with a few shots and a link to this thread.

 

:lol:

 

...but yes I sure have. 

 

http://www.prepar3d.com/forum-5/?mingleforumaction=viewtopic&t=6363

 

I just hope I don't have to bump the thread for a month to get a response like last time (the AI texture swapping issue). Maybe if I title my thread "something something autogen"  :lol:


 

Need to do more testing, but there does seem to be an anomaly here.

 

 

I wonder if testing out in the middle of the pacific might narrow down the sun/moon issues.

 

EDIT: Thinking about the KPIT shots where I was testing the sunrise, it is interesting that the lights themselves do not need to be in the frame, though I'm sure there is an airfield somewhere in the distance. What matters more, it seems anyway, is just that the night lighting system is active, lights in view or not.

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Whoops. This was lost between all those huge screenshots.

 

Yeah no worries, you know by now just to ignore me when I'm being a smartass  :lol:

 

I'm going to go try a flight or two now in the Q400, with the ASN beta, and we'll see how it goes. I do hope others will be willing to chime in either here or over at LM with their experiences, and I really hope this isn't just a side effect of the lighting changes made.

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I wonder if testing out in the middle of the pacific might narrow down the sun/moon issues.

 

 

It take a genius eh Brian?.... :lol:

 

So, in the middle of the Pacific... I still get a substantial drop looking at either the sun or moon when they sit on the horizon during dawn and dusk... :unknw:

 

Even stranger looking straight up gives me a huge drop - from 100+ to 40 :shok: looking straight down into the ocean gives me the highest fps, but this is regardless of TOD... but, only in the middle of the ocean.

 

Looking at the sun/moon at any other TOD is fine, just dusk/dawn, so there is something amiss here, with either me or P3D.

 

 

So, I am currently downloading the full 2.2 installer and will start from scratch with no add-ons, as this is plain stoopid :vava:

 

If anyone else can spare ten minutes to check some of this it would be good... those blue lights too.

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Unfortunately, this community is far more concerned with the icing than it is with the cake, so it looks like this will go nowhere either way.

 

1 minute to load the sim and have a look is a lot to ask I guess :unknw:

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Yeah probably... buts that’s okay I have few expectations. I am just about to install a virgin v2.2 and will see what happens.


 

I must say, I do like that icing too :blush:

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I like all of it too of course  :wub:

 

I guess I was just a bit grumpy seeing the thread on the LM forums drop to page 2 without a response (not even saying a dev response, just any response).

 

I know we all have different priorities, and I am well aware that for now I am definitely in the minority of the P3D user base, as someone that spends most of my time in the tubeliners near the large airports. I just had hoped that such a large and obvious perf hit would be worthy of a little investigation.

 

In any case, I am curious what your fresh install shows you. For me it made no difference. I'm going to go try and re-create your scenario in the ocean now.


Alright so again I can't really say I see much of a direct impact from the sun:

 

axv8.png

 

xzmz.png

 

2xqt.png

 

7osp.png

 

...and a quick dusk shot:

 

ng2e.png

 

Out here definitely isolates the lighting away though which is good.

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Alright guys, I have noticed the same dawn/dusk fps drop as well.  In fact I noticed it in v2.1 in certain scenarios.  When I am looking in a certain direction, the frame rate drop occurs, but if I change my view direction it goes away.  Also if I change the time of day it goes away, so something needs to be addressed by LM, which I am confident that they will.  I will add to the thread on the P3D site so it can get the attention it needs.  

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In any case, I am curious what your fresh install shows you.

 

 

No change... which is annoying, as I thought it might be one of my REX4 textures, or some other add-on.

 

Could someone [more than one if poss] please load the flight in the file uploaded below... unzip and add the files (ab.fxml and ab.WX) to your C:\Users\your name\Documents\Prepar3D v2 Files and then load the flight called 'ab'

 

Looking at the sun in this scenario tanks my frame rate into the low teens... though there may be other factors than the sun and it position, as above.

 

 

https://www.mediafire.com/?8hlm43bpzhsndml

 

Thanks... if its reproducible I can be reported, otherwise I need to look for a solution.

 

 

 

EDIT

Alright guys, I have noticed the same dawn/dusk fps drop as well.  In fact I noticed it in v2.1 in certain scenarios.  When I am looking in a certain direction, the frame rate drop occurs, but if I change my view direction it goes away.  Also if I change the time of day it goes away, so something needs to be addressed by LM, which I am confident that they will.  I will add to the thread on the P3D site so it can get the attention it needs.  

 

Thanks Mike... so there might be something in this. Good to know we're not alone.

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Nope, not alone. I will get some specifics in terms of scenarios that I see this occurring and come back with that information tonight.

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IIRC there has always been a drop at dawn/dusk in FSX. Had something to do with changing the lighting and the sky. FWIW, even during the day, if I am parked looking ahead at a terminal building and I pan around to look at scenery - the FPS increases when it's scenery and decreases when the airport buildings are displayed.

 

Vic

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