Dynamic Lighting Issues in P3D 4.2 - Lights Only Illuminating Ground at Certain Camera Angles

[MrYorkiesWorld 3]

 

Hi guys,

I've been having problems with P3D 4.2 for a week or so now.

I seem to be unable to see the taxi or landing lights illuminating the ground from inside of the PMDG 737-800 Virtual Cockpit unless I pan the camera at a certain angle. I can see the lights fine if I choose an exterior view in EZDOK, but the Virtual Cockpit seems to have this very strange issue.

I have recorded a short video showing the problem I am having in hopes that someone might be able to tell what the problem is?

I've literally just installed a completely fresh installation of P3D 4.2 and my addons which are listed below:

Active Sky for P3D4
EZDOK Camera
GSX Ground Services
Orbx FTX England
Orbx FTX Global
PMDG 737-800
Prepar3D (P3D) V4.2
PTA (P3D Tweaking Assistant) with Matt Davies Preset
REX 4 With Soft Clouds
Ultimate Realism Pack v1.1
Ultimate Traffic Live

I hope this is allowed, but if anyone can see from the video what the problem might be, I would be really grateful of any assistance. The video is below: 

In the video, I have also gone into my sim settings in hopes someone might be able to spot something in there which could be causing the problem?

 

Thanks!

Yorkie

 

[slait 169]

I have this same issue. Happens at many different airports, any aircraft, and at various times and angles. Many times as I'm taxiing it will suddenly appear again, and/or disappear.

I had this issue in 4.1 as well, but clearly has not gone away in 4.2. I'd also love to hear if anyone has any suggestions.

[GEKtheReaper 364]

Guys,

you should use the search option more often...

Plenty of videos and tests and also findings in here. Please also post this issue in the LM forum!

The last page of above topic shows UTL beeing the culprit. If you don't have UTL, then another traffic program could be the cause.

 

@YorkiesWorld: turn your camera towards an angle where the lights turn off then go into TaskManager and Kill UTLCLIENT.exe process! What happens?

Edited March 6, 2018 by GEKtheReaper

[slait 169]

3 hours ago, GEKtheReaper said:

Guys,

you should use the search option more often...

 

Thanks, though your presentation could use a little "refining".

Edited March 6, 2018 by slait

[GEKtheReaper 364]

24 minutes ago, slait said:

Thanks, though your presentation could use a little "refining".

1. Not sure what you mean by that.

2. Just to collect informations about the issue, could you please tell me (us) if you also use UTL and if the above "fix" does help?

3. If point 2 does indeed help, would you mind going to UTL forum and P3D forum, find the topic and post having the same issue?

Maybe collecting this in a single topic we might get heard by LM ;).

 

Thank you.

 

[Bob Scott 7,721]

So the short version without deep-diving into all sorts of other topics, is that P3D has a cap on the number of dynamic light sources it can render.  A large number of AI acft that use DL can run up the number of sources to the limit, and then your acft lights could be among those that are culled out when imposing the cap.  That's how I understand it.

Regards

 

[GEKtheReaper 364]

40 minutes ago, w6kd said:

So the short version without deep-diving into all sorts of other topics, is that P3D has a cap on the number of dynamic light sources it can render.  A large number of AI acft that use DL can run up the number of sources to the limit, and then your acft lights could be among those that are culled out when imposing the cap.  That's how I understand it.

Regards

 

Basically we (as there are more people) think that that is the case.

Unfortunately it is strange that the DL dissapear under some angles ONLY! E.g. in the above video taken from the cockpit (and also my videos) you will not see additional DL displayed but only that your's are turned off.

The big Q is: why doesn't P3D turn off other lights positioned further than you so that you don't get this annoying effect. As some others say (incl. some DEVS) there might be a BUG in P3D.

If more users would test and report about this, there would be an increased chance that "somebody" would dive into this matter not thinking it's isolated and due to faulty installs and so on.

[simbol 5,819]

17 hours ago, YorkiesWorld said:

 

Hi guys,

I've been having problems with P3D 4.2 for a week or so now.

I seem to be unable to see the taxi or landing lights illuminating the ground from inside of the PMDG 737-800 Virtual Cockpit unless I pan the camera at a certain angle. I can see the lights fine if I choose an exterior view in EZDOK, but the Virtual Cockpit seems to have this very strange issue.

I have recorded a short video showing the problem I am having in hopes that someone might be able to tell what the problem is?

I've literally just installed a completely fresh installation of P3D 4.2 and my addons which are listed below:

Active Sky for P3D4
EZDOK Camera
GSX Ground Services
Orbx FTX England
Orbx FTX Global
PMDG 737-800
Prepar3D (P3D) V4.2
PTA (P3D Tweaking Assistant) with Matt Davies Preset
REX 4 With Soft Clouds
Ultimate Realism Pack v1.1
Ultimate Traffic Live

I hope this is allowed, but if anyone can see from the video what the problem might be, I would be really grateful of any assistance. The video is below: 

In the video, I have also gone into my sim settings in hopes someone might be able to spot something in there which could be causing the problem?

 

Thanks!

Yorkie

 

Hi there

Try reducing the number of AI traffic, we discovered on the topic quoted below that this was the cause for DL disappearing for flood lights: https://www.avsim.com/forums/topic/531836-p3dv42-loss-of-dynamic-lights-and-acft-flood-lights/?page=3

Best Regards,
Simbol

[Bob Scott 7,721]

Could be that the light sources rendered are chosen depending on the field of view, which of course is affected by the direction you're looking, and are ordered by something other than distance from the camera, like perhaps something simple like lexicographic (by file or object name) loading order.

I think that to convince LM there's an issue, someone will need to run some extensive tests in the base sim only...lately LM seems to be spring-loaded to blame add-ons for nearly everything, continually posting a really annoying boiler-plate response to scores of problems that ask if the problem occurs without add-ons, and if not, contact the add-on maker, as if all unhappy interactions with P3D are the add-on maker's problem and not caused or exacerbated by P3D itself.

Regards

 

[paulwain 24]

I’m glad you mentioned this I noticed this today. 

 

Hopefully there’s a fix 

[Guest]

I believe the DL cap is 250 point lights and 250 spot lights per view.  V4.2 introduced LOD out lights that are less than a certain pixel size on the screen ... the default value in Effects.cfg is as follows:

; The [Light Detail Modifier] is used to LOD out lights that do
; not cover many pixels.
[Light Detail Modifier]
Minimum Pixel Size=15.5

You can try changing this value if you believe it might be the cause of this issue, lower values would allow for more DL.  I believe this is inclusive within the CAP determination per view ... so lowering the value may increase your total towards the cap (as it would allow more DL to render) ... so adjust carefully.

Cheers, Rob.

[LB777 100]

The limit is 256 lights per tile (point and spot lights combined), tiles being 16x16 pixels.

My understanding is there is no hard cap on the number of lights in your view as a whole, but since lights usually cover a relatively large portion of the screen anyway it would probably be hard to get past that 256 limit.

[Guest]

3 minutes ago, LB777 said:

The limit is 256 lights per tile (point and spot lights combined), tiles being 16x16 pixels.

That's not my understanding, I can't provide you a link to the discussion as it's not public put per Kevin Cartrette from LM:

"There is still a 500 cap, 250 point lights 250 spots lights per view. We may end up making this configurable if it becomes an issue, however performance will become an issue quickly with large number of overlapping lights per tile. Especially with SSAA/MSAA."

Do you have a source for your information as there appears to be some confusion?

Cheers, Rob.

[LB777 100]

52 minutes ago, Rob Ainscough said:

"There is still a 500 cap, 250 point lights 250 spots lights per view. We may end up making this configurable if it becomes an issue, however performance will become an issue quickly with large number of overlapping lights per tile. Especially with SSAA/MSAA."

Hmmm that's odd. My "source" is just looking at the shader code. There is a very straightforward buffer listing all the lights in the scene and its length is incremented by 256 for each tile.

Your quote does say "per view" though, so there might just be a global limit for the view in the C++ code which is independant from the one I mentioned.

Anyway I didn't write the code, so I'm sure what they say is true in one way or another

[Guest]

My understanding per LM was it did NOT end up being configurable ... so probably more to it than what's in the shader code.  Have you experimented with the shader code relative to this context?

Cheers, Rob.