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GP Layering problem

I am experiencing an issue where higher layer polygons are not being displayed on top of lower layer ones in P3D v3. An example is the attached. I created a parking lot and gave it a custom asphalt texture and a layer 24. I created a custom parking lot stripe texture and applied this to another polygon layer 30. It is my understanding that the layer 30 should be displayed on top of a layer 24 in P3D but that is not happening. If I place the layer 30 directly on top of the 24, it can't be seen. If I move it so that it is not over top of the layer 24 polygon, it is displayed (see picture #2). I am also noticing this on runway stripes. What is happening here? Thanks in advance for the assistance. I am using ADE 1.75. I just switched to 1.75 for this airport and I never did have this kind of issue with 1.70.



You may have noticed that, in addition to your own experiences with GPs made via ADE 1.75x, there are a few outstanding questions raised in other threads here at FS Developer that are likely to require further investigation by Jon and Don. ;)

Thanks for clearly identifying as many pertinent factors which describe the issues you have encountered with this.

Just to clarify, in the OP above you are not referring to CVX vector Airport Background (aka "AB") Polygons compiled via SDK SHP2VEC, and instead refer to GPs that were created from scratch in ADEv1.75x GP Tool as P3Dv3 SDK compliant MDL-based GPs, and NOT imported / converted from legacy format SCASM / ASM-based GPs ? :scratchch

And the GPs in ADEv1.70x that were created from scratch in ADEv1.75x GP Tool as P3Dv3 SDK compliant MDL-based GPs, and NOT imported / converted from legacy format SCASM / ASM-based GPs ? :scratchch

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Thanks for the reply. Yes these polys were created from scratch in the ADE 1.75 GP Tool. They were not imported or converted from an older version.
I don't know if the information available via Scruffyduck's "ScreenStepsLive" reference pages is completely up-to-date for the current feature set and procedures in the ADEv1.75x version of GP-Tool, but this may merit a review:


Also, if you have not already reviewed the information posted by Helli Hauck and Jon Masterson (aka "Scruffyduck") regarding layering priority of BGLComp-based default textured airport objects placed by ADE, this adds yet another "layer" of complexity to the airport design / modification process:


Then one may wish to review the insights shared by Jim Vile with the above BGLComp-based and CVX vector-based textured airport objects in this thread:


On a practical basis, unless one is applying specific visual enhancements to synthetic, very high resolution textures mapped onto MDL-based GPs made with Z-Bias Material Properties via P3D SDK, it is, IMHO, more practical to simply use visually enhanced custom photo-real aerial imagery compiled via SDK Resample. ;)

Hope this might help until Don returns. :)

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Thanks Gary, I will review this information. I may have found another bug. I created some water polys and I have no exclusions and I even took the airport background out but they are not showing up. I don't know if this is related or not.


Gary, I did have a photoreal using Resample but I removed that .bgl from the scenery folder thinking that it was causing the problem. Removing it did not help. The land class textures you see were all drawn in ADE 1.75 using stock land class types.
If you intended to use custom photo-real aerial imagery Land Class, one must make it with Land-Water Mask and Blend Mask image files submitted along with any Seasonal / Night image source files via a multi-source INF ...to be compiled by FSX / P3D SDK Resample. :pushpin:

The work-flow for this was recently discussed in some threads with links to pertinent tutorials here:




Gary, I tried that. I created a blend mask and I could see the photo real water but not the land class water. That is when I removed the photo real all together. I will check out the links you provided in case I am doing something wrong. Thanks.

Gary, I tried that. I created a blend mask and I could see the photo real water but not the land class water. That is when I removed the photo real all together. I will check out the links you provided in case I am doing something wrong. Thanks.
The Blend Mask only allows the aerial imagery texture image to "fade" into the FS Water Class texture 'color'; the Land-Water Mask is what provides the transparent, specular reflections, splashing / floating of certain SimObjects, wave patterns (not to be confused with shoreline wave effects) associated with a "Hydro" attribute ...on top of terrain textures.

A review of the linked info above will indeed help explain all that. :)

So after some more testing I have determined that on the first issue, with GP layering, it is always happening in P3D v3.4 but in P3D v 4.1 it is about 50/50. Half the time I will see the custom polygon runway markings as they should be and half the time they are gone. On issue #2 it appears that I can't create a water poly. I opened a new airport from stock and didn't do anything to it other than draw a polygon type water, lake non-perennial just outside of the airport. The polygon does not show in P3D. I can change the polygon to a land class type and it will show, just not water. I will continue to investigate.
Okay so my water issue is fixed. It was the type of water I was picking. If I pick non-perennial it will not show. I changed it to perennial and it shows now. Issue #1 with the GP layering is still on going though.
Did some testing and it appears that simply incrementing a layer by 1 will not necessarily cause it to be drawn over the top of a lower level poly. If I increase the numbers by 5, 10 or 15 (still haven't determined what the magic number is) then it works. Its still very sketchy though. As an example I have about 30 custom polys drawn on my runway. They consist of individual piano keys, runway numbers, centerline markers, touchdown markers, etc. I could not see any of these polys on the runway even though they were all 1 layer higher than the actual runway. I incremented 4 piano keys by 5 each so #1 was +5 more than the runway, #2 was +10 and so on. After I did that, ALL OF THE CUSTOM POLYS are now showing even though I didn't change the layer numbers on any except the 4 piano keys. It doesn't make any sense to me.

I am familiar with a recommendation for separating legacy SCASM / ASM G-Polys by at least 3 interposed layers, so that each G-Poly is placed on every 4th layer.

Have you tested that G-Poly layering configuration in P3Dv4 ?

Thanks for keeping us informed of your tests with G-Polys in P3Dv4 (and FSX). :)

I tried setting them at increments of 5. The base layer of asphalt was default 24. The runway markings I set at 30. The runway/taxiway yellow stripes were set at 30 with the hold short lines at 35 so they would show (in theory) on top of the lines. Now I don't see any markings on the runway except the yellow taxiway stripes where they come up on the runway for a short distance. It also appears that changing the layer # of any poly can affect the entire airport, not just polys on top of or below it. An example would be parking T's on the apron. I changed the layering on those and it affected polys being drawn on the runway. I really can't find any common denominator in my testing other than it is completely unreliable. There seems even be a difference in what is drawn in V3 and V4 of P3D. Some things I see in V3 and not in V4 or vice versa.

I think I am going to have to look at making my runway, taxiway and apron as a model instead of polys drawn in ADE.
Question......are you applying P3D Material Settings to your ground polys? If so, what Z bias values are you using. AFAIK, Z bias takes precedence over layering when material settings are used, please correct me if I'm wrong.

#1 When you fire up ADEx, which version do you select....P3D or FSX?
#2 If you select P3D AND run the P3D version, when you double click your GP, and the polygon window opens, do you select anything under the P3D Material Settings pull-down tab?

I have not had time to test the work-flow in ADE GP-Editor Tool on an example MDL-Based object output, and would be more familiar with the MCX G-Poly wizard due to the time I have spent working in MCX, but I found this statement by Don to be interesting: :idea:


ADE generates fully-PV4-compliant ground polys including the Z-bias offset. You don't have to add the z-bias manually; check the MAT3 blocks in the _GP.bgl files and you'll see it's already there.