ACTIVE Why do other regions stay enabled in the Scenery Library?

[Rob Ainscough]

I've noticed that when I switch regions from say FTX Global to Europe, I'll still see all the AU (Oceania) and NA (North America) regions enabled and checked in my Scenery library (P3DV2.2).  Note: I don't run FTX Global in hybrid mode.

 

As you know, the more enabled entries one has in the scenery library the increase in "blurries" (I hate using that term) so I usually just uncheck all the NA and AU entries when I'm only flying EU.  I haven't noticed any issues with this approach, but I am curious why those regions are enabled by FTX Central when I switch from Global to Europe?

 

Cheers, Rob.

 

[pmb]

I've got a related question: Why are the Global Vector entries not switched off when you are flying in, say, Australia (the region)? Switching them off should not hurt, but having them on might interfere with the regions and/or affect performance there.

 

Kind regards, Michael

[Holger Sandmann]

Hi guys,

 

actually, I don't know anything about increasing blurries due to more entries is the scenery library; FSX reads scenery file headers for their geographic grid location and only fully loads those files surrounding the current user aircraft. Besides, If we didn't keep all regions enabled then people would complain that they couldn't do long-distance flights from NA to EU etc.

 

As for the Vector entries they are not tied to FTX Central as Vector has its own control panel. Again, we don't know whether people plan on flying within or between FTX areas or from default/vector areas to regions so we can't just force Vector to off. The only FTX regions in which there might be local interference from Vector are AU BLUE and GOLD as they don't fully replace all waterbodies and shorelines as the other regions do; if in doubt temporarily deactivating Vector's _EXX, _CVX, and _OBJ entries should do the trick (the other two entries are related to airport and object placements).

 

Cheers, Holger

[Rob Ainscough]

Hi Holger,

 

In FSX and P3DV2.2 (this may change in v2.3) the more "enabled" entries in the scenery library the more work for the CPU to determine "who's on first" (what textures to load).  It was well known that adding many entries into a scenery library would cause "blurries" and this holds true for P3DV2.2 also as that system hasn't changed significantly in P3DV2.2 over FSX.

 

As one moves thru the Simulated world, the "enabled" entries in the scenery library are referenced and evaluated constantly as aircraft position changes ... the library is indexed but it still has a overhead associated with it.  For example suppose the scenery library is processed at 18Hz, if there are 100 enabled entries vs. 300 enabled entries then considerably more processing is occurring every cycle.

 

Obviously I can't say for sure how the P3D system works, but it's behavior is very similar to this type of processing and exhibits the same (exact) issues one would find in FSX when one's scenery library gets very large.

 

As a result I disable those regions I'm not going to be flying into or around.  In my case where I just want to fly EU, I will disable 38 other FTX entries (AU, NA).  This greatly reduces the changcs of me getting into a "blurry" situation especially with higher speed aircraft using higher graphics display settings.

 

I'm assuming there is no "harm" done disabling entries I know I will not be flying into?

 

But you answered my question, you keep all the entries enabled for those that do region to region flights.  It might be handy if FTX Central had an option such that a region selection will disable the other FTX region entries in the scenery library ... let the user decide what they prefer.

 

Here are some pictures of what I'm talking about from my Scenery Library, you'll see all regions enabled even though in FTX Central I selected Europe.

 

 

 

 

Cheers, Rob.

[Holger Sandmann]

Hi Rob,

 

nope, there's no harm deactivating entries other than the Orbx libraries.

 

I'm not that familiar with P3Dv2 yet but I'm not convinced that there really is a noticeable impact due to more scenery library entries or that P3D is "dumber" in this regard than FSX. You speak of "well know", can you post links that provide quantitative information on that or statements to that effect by LM?

 

The smallest grid block that the terrain engine typically loads scenery files in is QMID11 (~20x20km) with sub-blocks in 1.2km x 1.2km steps. Thus I doubt that there's a need to poll index files at 18Hz (where does that number come from?). It should be possible to check with ProcessMonitor for how often the index files are really accessed. 

 

We're generally reluctant to add more complexity to control panels because it tends to lead to more confusion and thus more support calls  ...unless there's a clear case to be made for noticeable benefits of having "unused" entries deactivated.

 

Cheers, Holger

[Rob Ainscough]

As far as scenery library goes, I'm pretty sure there isn't any significant difference between how FSX works with it and how P3D works with it ... both in my opinion are pretty "dumb" but they are also extremely flexible and the system exists for the flexibility of 3rd party content providers.

 

I'll try to find the AVSIM thread I started on this topic many moons ago ... I had demonstrated (video and screenshots) showing the impact of having too many entries in the Scenery Library, it was very drastic and was a major cause of "blurries".  Video was before and after ... where before is with all the entries in the scenery library enabled, and after is with just those entries need for fligth area - that being the ONLY change.  But Firehawk (AVSIM mod) and others apparently had already known about this "solution" to reduction in blurries so I assumed it was common knowledge.

 

18Hz ... just pulled that out of thin air for example purposes ... no idea the actual coded process.

 

Process monitor can show the index file access, but there are so many files it's not terribly useful unless someone has a month or so to go thru the data.  It's not so much the file access, but the "decision" process on a thread to determine if indeed anything needs to happen ... hence making the thread run longer and taking away time from hi-res textures to load.

 

Good to know that I can disable entries without harm.

 

Cheers, Rob.

[John Dow]

OK I just ran two long tests in the A2A C172 to test the idea that unticking regions makes a difference.  One was from YWOL towards YSBK, the other was from 1S2 Darrington to the tops of the nearby mountains.  The verdict?  Not a shred of difference.

 

In the YWOL test I took off to the south, climbed to 1000', turned north and flew along to confirm allvisible scenery was nice and sharp.  I then increased the sim rate to 4X until I got to the escarpment and then 16X over the bush to about Holsworthy.  By then the landscape was nice and blurred in all directions.  Returning to normal sim rate saw the scenery take approx 30 secs to return to sharp in all directions.  There was no difference between having just the AU region and YWOL and OZx ticked, and having every scenery box ticked.  (Just to confirm, I spent several minutes unticking every single scenery item except the MS base files and the files needed for this flight. Then I spent several minutes ticking every single scenery item for every country, region, airport etc.

 

The second flight was similar, first one had every scenery region ticked, the second had all regions unticked except PNW.  In each case, climbing out of Darrington towards the range to the SW, first at 1X, then 2X, until I got over the ridge at 5000 ' approx, saw much of the close-up ridge details blurry, while the distant views were quite sharp. It took 30-60 secs for all the ridges to pop into sharp focus, and they stayed that way.  Once again, NO DIFFERENCE.

 

So is the myth busted or do I have a super computer?  I think the former is more likely.

[Rob Ainscough]

So is the myth busted or do I have a super computer?  I think the former is more likely.

 

It's no myth I can assure you.  How many scenery entries do you have in your library and what types (Airports, Photoreal, etc. etc.).  The testing I did was mostly with Photoreal (MSE) and I didn't need to go thru any of the additional steps you did to duplicate ... just takeoff from an airport in a Jet and within 1-2 minutes the blurries happen.  Disable all the non-relevant scenery entries and the blurries don't happen ... it's a really simple test no need to increase sim rate to induce.

 

Your display settings (all 5 screens worth of settings) will also be an important factor, especially your LOD.

 

For me, the problem would start to surface around the 513 entry mark (scenery library entries).

 

Cheers, Rob.

 

EDIT: please don't take this as me suggesting a problem with Orbx FTX Central, I was just curious when I select Europe, Oceania and North America stay enabled.

[Rob Ainscough]

Finally found the thread (going back to August 2013) I had done on testing this (this was FSX but same holds in P3D) -- from the images you can see the impact on "blurries" when many items are enabled in the scenery library.  (be sure to look at the linked images).

 

http://forum.avsim.net/topic/414988-profiling-fsx-via-process-monitor/?p=2733904

 

Just want to be clear I'm not associating any "fault" here, just providing examples of why having a large scenery library with everything enabled can cause "blurries".  Per Holger's comment that they are all enabled in case someone is flying from one region to another which is understandable ... only request was to allow an option to not enable those entries when not selected in FTX Central.  I personally don't see how this could add "confusion" (especially if defaulted to original way you have it now ... just an option for those that have a lot entries in our scenery library) but it could have the potential to remedy support threads about "blurries".

 

This isn't about me and my desires, as I pretty much figure out ways to work around any issues I find.  So please take this as just sharing information and not pointing of fingers. 

 

Cheers, Rob.

[MichaelMoe]

Finally found the thread (going back to August 2013) I had done on testing this (this was FSX but same holds in P3D) -- from the images you can see the impact on "blurries" when many items are enabled in the scenery library.  (be sure to look at the linked images).

 

http://forum.avsim.net/topic/414988-profiling-fsx-via-process-monitor/?p=2733904

 

Just want to be clear I'm not associating any "fault" here, just providing examples of why having a large scenery library with everything enabled can cause "blurries".  Per Holger's comment that they are all enabled in case someone is flying from one region to another which is understandable ... only request was to allow an option to not enable those entries when not selected in FTX Central.  I personally don't see how this could add "confusion" (especially if defaulted to original way you have it now ... just an option for those that have a lot entries in our scenery library) but it could have the potential to remedy support threads about "blurries".

 

This isn't about me and my desires, as I pretty much figure out ways to work around any issues I find.  So please take this as just sharing information and not pointing of fingers. 

 

Cheers, Rob.

 

 

i am also in the club selecting any entrys in the scenery lib.  before a flight using the editor so i would also be happy for an option in the Central at least for all ORBX Regions when not in Hybrid

 

Not in Hybrid meens i am not going to fly in and out of regions 

 

Michael

[boleyd]

Using a jet to test versus a GA makes test comparison difficult. Artificially speeding up the flight distorts the processing overall and may be invalid. I assume the Spirit test was done on SSDs. A large file set may entail turning a "page" in the index and that may have a coding issue carried over from FSX.