Ground poly is flickering (again) despite of flattening.

[jtanabodee]

Hi,
I was about to release my VTBS for P3Dv4. When I let beta testers test it, they report flickering of all the ground polys. I don't know why I don't have it on my computer. I did some changes of altitude in ADE (1.79 for P3Dv5) and it generate the file ***_ALT.bgl. I sent to them but no matter what I did, no solve. There is no other addon on the testers's computer, the same as mine. But why they have flickering but I don't. Still searching for the solution for a week.
Did you have ever encounter that experience? and how did you find the solution? May be that can enlight me how to find the answer. The video like is here: https://www.dropbox.com/home/Public?preview=2021-08-30+14-49-39.mp4


Thanks for any comments.
Tic

 

[gadgets]

Without your .ad4 file, I can't tell much, other than this is not what is typically regarded as flickering, (i.e., Z-fighting).

As an airport, your's is at the extreme end of things. I wonder if it's not just a case of resource exhaustion - especially since it doesn't happen on some computers (such as yours)

 

[jtanabodee]

Thanks gadgets, your reply make me think the other way around.......

I start to have flickering in my computer too. So, I think it might has nothing to do with ADE file, flattening and altitude. As far as I can see, only the first Z-bias ground polyp cause flickering. I will test that again. Do each layer again one at a time and see what happens.

 

[jtanabodee]

Still no luck, I have check all ground poly and remove them one at a time. Still flickering even there are only one layer of ground poly. I think flatenning is the problem.

 

[GaryGB]

Still no luck, I have check all ground poly and remove them one at a time. Still flickering even there are only one layer of ground poly. I think flatenning is the problem.

Hi Tic:

Your file on DropBox is requiring registration in order to access it.

If you make the file available in a non-restricted area of DropBox or another download site, others here may offer input on your issue.

GaryGB

 

[gadgets]

While eliminating GPs and layers one-by-one may eventually resolve the issue (on your system), if it's a load issue, every machine will react differently.

I would suggest you temporarily delete several large blocks of scenery and see if that helps. If it does, then a load issue becomes more likely.

 

[jtanabodee]

Hi Tic:

Your file on DropBox is requiring registration in order to access it.

If you make the file available in a non-restricted area of DropBox or another download site, others here may offer input on your issue.

GaryGB

I have uploaded to Y tube. Thanks for letting me know it is not visible. here it is:

 

[jtanabodee]

While eliminating GPs and layers one-by-one may eventually resolve the issue (on your system), if it's a load issue, every machine will react differently.

I would suggest you temporarily delete several large blocks of scenery and see if that helps. If it does, then a load issue becomes more likely.

I did that yesterday. The first Z-bias layers, no problem. But a few layers after that, it cause flickering. I have checked Zbias and those are in order -1,-2,-3. Each bgl file has the same material. But there are more than one bgl file share the same Z-bias. Could that be the problem? I have tried to eliminate that but nothing helps.
How can we confirm that the surface of the airfield is the same elevation?. I know that FSX has a tool. But I have tried in P3D but it doesn't work.

 

[GaryGB]

How can we confirm that the surface of the airfield is the same elevation?. I know that FSX has a tool. But I have tried in P3D but it doesn't work.

Hi again, Tic:

What FSX "Tool" are you referring to which is not available for use in P3D ?

GaryGB

 

[gadgets]

The first Z-bias layers, no problem. But a few layers after that, it cause flickering. I have checked Zbias and those are in order -1,-2,-3. Each bgl file has the same material. But there are more than one bgl file share the same Z-bias. Could that be the problem?

Just to make sure you didn't misinterpret my earlier messages, what I saw on my system was not typical "flickering". (Incidentally, I had no difficulty accessing your video on Dropbox.)

ADE-GP automatically assigns Z-bias based on specified layer. From your statement above, it would seem you created the ground polys other than with ADE-GP and are assigning Z-bias manually. If that's the case, then I'm probably not going to be of much help. But, to answer your specific question, theoretically, at least, two files containing materials with the same Z-bias and attempting to display those materials at the same elevations seems problematic.

 

[GaryGB]

Hi Don:

Perhaps Tic could help us help him better, by telling us if he created his G-Polys using P3D SDK Material for Z-Bias Level "functionality":

https://www.prepar3d.com/SDKv5/sdk/modeling/3ds_max/modeling/modeling_materials.html#ZBiasLevel


..or if instead, he is using a FS-8 SCASM / ASM, FSX, or P3D 3D model G-Poly without the P3D SDK "Z-Bias level material setting".

GaryGB

 

[gadgets]

If he used ADE-GP to create the ground polys, Z-bias is set automatically. There is no opportunity to set z-bias independently. So, it seems unlikely that ADE-GP was used.

Perhaps Tic could help us help him better, by telling us if he created these G-Polys using P3D SDK Material Property for Z-Bias "functionality":

Seem to me he already has, given the number of times he's mentioned "Z-bias". What he hasn't told us is whether or not he has enabled the functionality by also selecting "noZWrite"

In any case, as I've said twice now, on my system at least, the effect is not typical "flickering". Instead, the display remains stable until the user A/C is moved a significant difference. Then one or more GPs (that may not have been displayed previously) appeas textured while some others that were displayed before dim, become untextured or disappear. The scene is so complex it's difficulty to really understand what one should see at any instant.

 

[GaryGB]

If he used ADE-GP to create the ground polys, Z-bias is set automatically. There is no opportunity to set z-bias independently. So, it seems unlikely that ADE-GP was used.


Seems to me he already has, given the number of times he's mentioned "Z-bias". What he hasn't told us is whether or not he has enabled the functionality by also selecting "noZWrite"

In any case, as I've said twice now, on my system at least, the effect is not typical "flickering". Instead, the display remains stable until the user A/C is moved a significant difference. Then one or more GPs (that may not have been displayed previously) appears textured while some others that were displayed before dim, become untextured or disappear. The scene is so complex it's difficulty to really understand what one should see at any instant.

Sorry, Don, but I am not certain that I understood what you meant above.

When you stated (twice ) "on my system", are you alluding to the fact that you have a working copy of Tic's G-Poly, and/or his *.AD4 file ?

Or are you only interpreting what you see in his posted video (...like I am doing, since I do not have anything to analyze but that video) ?

Thanks in advance for your clarification of this.

Indeed, it is curious when we see: "...one or more GPs (that may not have been displayed previously) appears textured while some others that were displayed before dim, become untextured or disappear."


One might wonder what the cause actually is without access to the G-Poly BGL(s) and all source files for those G-Polys.

GaryGB

 

[gadgets]

When you stated (twice ) "on my system", are you alluding to the fact that you have a working copy of Tic's G-Poly, and/or his *.AD4 file ?

Or are you only interpreting what you see in his posted video (...like I am doing, since I do not have anything to analyze but that video) ?

The latter. Incidentally, while I was able to download the video earlier this week, like you, I am now being asked to log-in.

 

[GaryGB]

AFAIK, because each 'entire' G-Poly seems to flicker, it implies the issue is unlikely to involve a AB Flatten with 1+ non-level vertex Altitude value.

So IIUC, that might focus Tic's troubleshooting on Z-Bias issues, and perhaps also, "excessive transparency" in 1+ G-Poly blend mask channel.

I am also wondering whether / how he applied LODs and MIPMAPs to his G-Polys in question.

GaryGB

 

[jtanabodee]

What FSX "Tool" are you referring to which is not available for use in P3D ?

It is TCalcX. It will show the coordinate and the ground altitude. So, I can check that the ground is totally flat.

Seem to me he already has, given the number of times he's mentioned "Z-bias". What he hasn't told us is whether or not he has enabled the functionality by also selecting "noZWrite"

I have done in in Gmax and export and FSX.MDL. I use MCX to assign the Z-bias level. The material I have set according to P3Dsdk and, of course, "noZWrite" was already set as well. I have done VTSP and other small airports, there is no such flickering. But this is the bigger one. That the problem from Z-bias, right? I will switch to FS2002 style then. I have been struggled on this issue almost 2 weeks now.

 

[gadgets]

I doubt it is a flattening issue. Compete GPs/taxiways and runways are disappearing and re-appearing. If there were "bumps" in the elevation, only those parts underground would disappear (and they would not likely re-appear based on the position of the user aircraft.)

You seem to have assumed the issue is Z-bias related - to the exclusion of all else. But, that's not what I'm seeing. It's as if depending on the position of the user aircraft certain elements of the display are simply not being drawn, which suggests a video or load issue. If you have only the airfield (i.e., runways, taxiways, aprons and flatten) and the ground polys, does the problem still occur. If it does, then you know where to look. If it doesn't than add the other elements one-by-one, until it does.

Incidentally, TCalc is a third party tool. I've forgotten the name of the author. It is not part of FSX but doesn't seem to be available any longer. My SlewMaster performs similar functions.

 

[GaryGB]

It is TCalcX. It will show the coordinate and the ground altitude. So, I can check that the ground is totally flat.

As Don and I both stated, the G-Poly flickering anomaly is not likely due to a CVX vector AB flatten vertex altitude issue.


But for future reference regarding use of TCalcX_003 by Richard Ludowise (aka "rhumbaflappy"), which IIRC, works in FSX and P3D, see:

https://www.fsdeveloper.com/forum/threads/tcalcx.446829/post-837040

I have done in Gmax and export an d FSX.MDL.

I use MCX to assign the Z-bias level.

The material I have set according to P3D sdk and, of course, "noZWrite" was already set as well.

I have done VTSP and other small airports, there is no such flickering. But this is the bigger one.

That the problem from Z-bias, right?

I will switch to FS2002 style then. I have been struggled on this issue almost 2 weeks now.

IIUC, you have exported a FSX MDL flat / level 3D model as a G-Poly.

FSX MDLs do not have an ability to use "true" Z-Bias, even if it has been "mapped" onto it.


Arno's MCX G-Poly Wizard offsets FSX MDL G-Polys from the base plane by fractional Meters to 'emulate' Z-Bias.

However, this is not a "true" Z-Bias, and may still incur various risks for several run time display anomalies.


FSX G-Polys can in rare circumstances be adjusted to minimize flickering artifacts of Z-Buffer fighting and Shadow attribute anomalies.

But FSX G-Polys are also likely always going to show Sky Blue flickering artifacts in Top Down view in FSX / P3D.


AFAIK, most developers do not attempt to use FSX MDLs for G-Polys for the above cited reasons.

https://www.fsdreamteam.com/forum/index.php?topic=7852.45


BTW: Additional info on eradicating some types of "flickering":

Understanding Cameras in FSX - FS Tips & Addons

Learn how the cameras in FSX are configured, and how to make your own, including an aircraft, cockpit and fixed camera.

www.fstipsandaddons.com

https://www.google.com/search?q=FSX+ClipMode=Minimum&client=firefox-b-1-d&ei=U1UyYbvTJJvPtQau3r-YDg&oq=FSX+ClipMode=Minimum&gs_lcp=Cgdnd3Mtd2l6EAwyBQgAEM0CSgQIQRgBUJe9iQFYl72JAWDOy4kBaAFwAHgAgAHBAYgBwQGSAQMwLjGYAQCgAQKgAQHAAQE&sclient=gws-wiz&ved=0ahUKEwj7yOuzpOPyAhWbZ80KHS7vD-MQ4dUDCA0


Your options include use of a legacy FS8-style 3D model SCASM / ASM G-Poly which IIUC, does display via a "true" Z-Bias attribute in P3D.


You may also use MCX to export a native P3D (not FSX) SDK 3D G-Poly MDL which can display a "true" / "mapped" Z-Bias attribute.


IIUC, to do this you must create G-Polys using P3D SDK Material for Z-Bias Level "functionality":

https://www.prepar3d.com/SDKv5/sdk/modeling/3ds_max/modeling/modeling_materials.html#ZBiasLevel


GaryGB

 

[gadgets]

Tic, I appreciate there's a certain pride in successfully using "original" tools to create a "modern" project. But yours has so many elements - GPs alone number in the hundreds - that the possibility of error is very high. Additionally, two difficulties with using Gmax to create GPs is that (1) the end results require post-processing to be useable and (2), there are no diagnostic tools when things don't go as intended.

ADE has several "import" functions, including one for the airport and one for GPs. While the GP import (from .asm) function is not perfect, especially with the VERY complex situation you have created - importing your airport and the associated GPs into ADE may reveal issues that otherwise would not be apparent. As well, if the import is successful (or you are able to correct it as necessary), you then have your airport in a form that can be compiled for any version of FlightSim (i.e., FS9/FSX/P3D) without any post-processing or other manual intervention for things like Z-Bias. It might be worth a try.

 

[GaryGB]

If he used ADE-GP to create the ground polys, Z-bias is set automatically. There is no opportunity to set z-bias independently. So, it seems unlikely that ADE-GP was used.

Hi Don:

My apologies for a lack of familiarity with the latest version of ADE GP functionality.


If P3Dv4.x and P3Dv5.x SDKs are installed, does ADE-GP output G-Poly MDLs native to those P3D versions with 'true' Z-Bias Level "functionality" ?

https://www.prepar3d.com/SDKv5/sdk/modeling/3ds_max/modeling/modeling_materials.html#ZBiasLevel


Thanks in advance for your further detailed clarification of your ADE-GP option.

GaryGB