P3D v4 Clouds show over PBR transparency

[mole_man99]

HI

Just checking if this is known bug or limit of PBR, or something amiss with how I do things.

I note that clouds, airport lights, aircraft textures will layer over a PBR plane with transparency, as you might use for fences. It does not happen for the models in the screenshot below if I disable PBR, only if PBR is set to true.

I use MCX to setup PBR. Here are the settings. I have tried Z-Bias 0, -50 and +50, 50 and many numbers inbetween.

 

[robystar]

Have you tried altering the alpha test level?

 

[mole_man99]

Yes, I also tried first to set it up as default transparent non-pbr, tested and it worked, then selecting PBR true, and you get the effect as above.

Maybe it is an MCX issue. If anyone could confirm they can make transparent PBR plains work correctly by exporting from max and not using MCX, before I pester Arno.

For the item above, I have defaulted to specular type texture. It works fine and I probably won;t change it now, but just intertested in this issue for future.

 

[robystar]

Just try anyway to change it to another level to make sure it is not a alpha test level issue due to the PBR.

 

[mole_man99]

I don't think PBR actually uses the z test. I have tried many setting (greater 128, greater 4, less 4, always 128, etc). All have the same result if PBR is set to true, and translucent render mode.

Opaque and masked render modes do not use the alhpa.

Z-bias is used to layer textures with alphas, but it seems to ignore stock scenery items, like clouds, ai aircraft, airport lights, the beacon towers, etc. I have tried 0, -4, -50, even -128 even though I read 50 is the limit.

If PBR should use the alpha test, then it may be an MCX issue. If someone can confirm it works fine by SDK export methods only.

 

[robystar]

Well, it seems your fence parts are also disappearing behind the clouds. That is what makes me wonder!

 

[mole_man99]

The fence in the image is also pbr texture. You can see how it lays over the blast fence correctly, but the clouds cut it. The two pbr objects play nicely together, just not with other sim items. Switch both to non pbr and all is well.

 

[Christian Bahr]

I have tried 0, -4, -50, even -128 even though I read 50 is the limit.

Hi.

In the P3Dv4 SDK it is described that the order of drawing PBR textures do not have negative z-bias values but have positive values: "Decal Order: Using values between 1 and 50, you can set and order the layering of ground polygon textures above the default airport aprons, taxiways and runways."

Other than ordinary z-bias values, the PBR textures begin with "1" (Decal Order). So the first drawn texture has the value 1:

I had previously tested this with textures for a ground layout. Whether that also applies to PBR Textures of 3-D objects, I do not know.

 

[RED COOL]

Hi.

In the P3Dv4 SDK it is described that the order of drawing PBR textures do not have negative z-bias values but have positive values: "Decal Order: Using values between 1 and 50, you can set and order the layering of ground polygon textures above the default airport aprons, taxiways and runways."

Other than ordinary z-bias values, the PBR textures begin with "1" (Decal Order). So the first drawn texture has the value 1:


View attachment 49465



I had previously tested this with textures for a ground layout. Whether that also applies to PBR Textures of 3-D objects, I do not know.

Hello i can't get my Ground polygon to use the alpha channel of the deffuse
i use the Translucent render mode but i still get black background

 

[Christian Bahr]

i can't get my Ground polygon to use the alpha channel of the deffuse
... i use the Translucent render mode but i still get black background

The SDK describes that it typically uses "masked" rather than "translucent". Such as the alpha channels for fences or trees. Whether it is also applicable to ground polys, I'm not very clear. So, can you try "Masked", please?

Opaque Used for Opaque surfaces.
Masked Used when there are masked out regions based on the albedo alpha. Typically used for fences or vegetation.
Translucent Used for Translucent surfaces. Translucency is based on final albedo alpha.

 

[RED COOL]

But i have some gradient alphas in many textures and i have mip mapped DXT 5 textures

 

[RED COOL]

@Christian Bahr
i tested with masked and with translucent and still the same
i used use alpha to coverage and the masked to 0.5 but still the same non-transparent textures

however look at those pictures

using masked render mode :

using translucent render mode :

there is a diffrence
but not what i was expecting

 

[haykal17]

i met same problem today when trying out pbr window, the albedo have alpha 60%

anyone got any idea?

thanks