P3D v4 PBR headache

#41
The Albedo Map (which can contain 1 or 2 textures - Base Color (RGB Channels) and/ or Smoothness (Alpha Channel).
I'm pretty confused with all of this, but the above is the thing that I find probably most confusing. It seems that the smoothness channel can be either in the metallic's or the albedo's alpha channel, is this correct? From the SDK documentation:

Albedo Map: Contains the base color texture for the material.
Metallic Map: Map that determines the metallic nature of the material. The metallic map must also contain a smoothness map and potentially an ambient occlusion map. These need to be packed in the following channels: R = Metallic, G = Occlusion, B = Empty, A = Smoothness.

And then it says:

Smoothness Properties - Smoothness Source
MetallicAlpha
The smoothness map is located in the alpha channel of the metallic map.
AlbedoAlpha The smoothness map is located in the alpha channel of the albedo map.

So it does seem like the smoothness can be in either one of two files. But... there's nothing at all about the 'normal' alpha mask of the albedo (diffuse) that defines opacity? So here's two more questions:

1) why would one want to put the smoothness channel in the albedo's alpha channel?
2) If you do put the smoothness in the albedo's alpha, then where do you put the 'normal' alpha mask/opacity? Normally the albedo's alpha is where you put that information? I ask this question all the more so because of this passage under "Masked properties":

Use AlphaToCoverage Uses the alpha channel to determine if the masked section should be visible or not, allows for anti-aliasing support on masked materials. You will still want to set a masked threshold to use for shadow support.

It just doesn't say which alpha channel it looks at?
 

Pyscen

Resource contributor
#42
Hello Benjamin...

The "Use AlphaToCoverage" (See Picture 1) is a Boolean switch ("On" or "Off") and according to the SDK: This is to be used in conjunction with (in the Render Mode) of "Masked" and "Typically used for fences and vegetation." (see Picture 2)

3dMax Screen.png


Also, according to the SDK, the "Masked" Render Mode and "MaskedThreshold" is having to do with the Albedo Map's - Alpha Channel. Therefore, the time to use the Albedo's Alpha Channel other than for the "Smoothness" texture is when a Masked Render mode is needed or done.

P3D-SDK.png


At this time, I do not know if MCX has this "Render Mode" Option... Will have to look tomorrow... getting late here. Arno, may need to know, if it isn't there and maybe need a small sample of such.
 
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#43
Hello Benjamin...

The "Use AlphaToCoverage" (See Picture 1) is a Boolean switch ("On" or "Off") and according to the SDK: This is to be used in conjunction with (in the Render Mode) of "Masked" and "Typically used for fences and vegetation." (see Picture 2)

[...]

Also, according to the SDK, the "Masked" Render Mode and "MaskedThreshold" is having to do with the Albedo Map's - Alpha Channel. Therefore, the time to use the Albedo's Alpha Channel other than for the "Smoothness" texture is when a Masked Render mode is needed or done.

[...]

At this time, I do not know if MCX has this "Render Mode" Option... Will have to look tomorrow... getting late here. Arno, may need to know, if it isn't there and maybe need a small sample of such.
I think you may have found the answer, Doug! Rather than render mode "Masked", there is another render mode that looks to be what I might be looking for: Translucent, and it states that this is affected by the albedo alpha. So I think that's the answer, right? If I were to include an alpha mask in the albedo, like you'd do with the diffuse in a non-PBR texture, you should be able to make materials translucent, or mask them out entirely, byt including the opacity/alpha mask in the albedo alpha channel and steting the render mdoe to translucent, which would tell the rendered to look at the alpha channel for the opacity information. This setup seems very similar to non-PBR materials, actually. In fact, I have seen in a Substance tutorial that one can make an opacity map, so when one exports the textures you could probably set up the export options in such a way that the generated opacity map becomes a greyscale alpha map for the albedo. Still makes me wonder why one would put the smoothness/glossiness channel as the albedo alpha though... That doesn't make much sense to me.

EDIT: Well hello, atcually that's exatcly how Stevo set up his export options :) /END EDIT

All this relates back to what Thorsten asked a while ago:

Don't want to hijack this thread but does anyone know how to set up a transparent material in Max using PBR materials? The opacity map isn't available for PBR materials so all my transparent materials are rendered opaque in the viewport. (of course in the sim everything is ok)
Thorsten, were you ever able to get translucent materials to work? It does seem like the opacity map is in fact the albedo alpha as we are used to from non-PBR textures, as I outlined above. If you did get it working, did you get it working by the method I outlined above? (Note I haven't tried any of it yet... But hopefully in the coming few weeks)
 
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Pyscen

Resource contributor
#44
Hello @Thralni

Yes, there are 3 Render modes: Opaque, Masked, and Translucent. The 'Masked' and the 'Translucent' options dictates how the Alpha Channel of the Albedo Map is to be read along with Boolean option on "where" the 'Smoothness' texture is also. I'm assuming you can't (or shouldn't be able to) intermix those options. Maybe someone who has 3DMax can check this... or try in MCX (just to confirm that one can't or shouldn't be able to).

Let's not confuse an alpha mask ("Masked") with a 'Normal' alpha channel use ("Translucent"), there appears to be differences in the 2.

I can confirm that MCX does have the 'Masked' Render Mode option.

EDIT: I have made the added information above in what DXT format should be used and when.
 
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#45
Hello @Thralni

Yes, there are 3 Render modes: Opaque, Masked, and Translucent. The 'Masked' and the 'Translucent' options dictates how the Alpha Channel of the Albedo Map is to be read along with Boolean option on "where" the 'Smoothness' texture is also. I'm assuming you can't (or shouldn't be able to) intermix those options. Maybe someone who has 3DMax can check this... or try in MCX (just to confirm that one can't or shouldn't be able to).

Let's not confuse an alpha mask ("Masked") with a 'Normal' alpha channel use ("Translucent"), there appears to be differences in the 2.

I can confirm that MCX does have the 'Masked' Render Mode option.

EDIT: I have made the added information above in what DXT format should be used and when.
Thanks for the helpful comments, Doug. Can you elaborate on the difference between the two? To me the "Masked" function always seemed like a more limited version of the "Translucent" option, in the sense that I can use Translucent for the same purpose one would use "Masked", but not vice versa. E.g. when I make taxi lines, the taxi lines have a grey value so they appear a little translucent, but the surrounding areas are entirely black, so that these do not appear at all. With "Masked" you can set a parameter above which the taxiline shows and the surroundings disappear, but the taxiline itself will be opaque. Hence "Translucent" should have the same effect as "Masked", though perhaps there is a performance cost and that's what the difference is?
 

Pyscen

Resource contributor
#46
I will try... :) to explain the differences.

The 'Masked' Render mode is limited (or even simplistic) because it doesn't use any color between white or black (no form of gray coloring used) in the Alpha Channel of the Albedo. The areas, say for a bush or a tree, will only be white. The areas not apart of the bush or a tree would be black. There would be no need for any grayscale or gray (fading effect - but maybe that's what the MaskedThreshold value is for, at least I think so) area for such, because its solid. Granted though, leaves on a tree can be transparent to some degree (some light does come through). I'm not fully sure on the workings of the MaskedThreshold value as of yet. The SDK does state that the "Masked" Render Mode is typically used for fences and vegetation.

The 'Translucent' Render mode would be used such as for glass or any area that is not fully opaque (partially transparent)...

So, the main differences between the 2 would be based on what type of material it is... is it solid or transparent in the real world.

Your example, taxilines, would fit, I think, more in the 'Masked' Render Mode category. Granted, the 'Masked' or 'Translucent' Render Modes can be interchangeable, but one of, 'Masked', would use less memory, due to its size. That is, if you used DXT1 1-bit alpha compared to DXT5 (ARGB 8, 8, 8, 8).

I hope that clears it up (looking through a window) :).
 
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#48
hey
is it normal that i got some red and yellow maps as metalic maps after substance export ?
EDIT : i think yes cus i tested in 3Ds ( not yet in P3D ) but what DDS format should i use
i'm about to export but i still have DDS format problem
Red colour is produced normally when your Green (AO) channel are towards black/darker. When it is towards white/lighter, you get greener metallic map. That is what I found from my experiment.
 
#50
yo guys
i found out that y model doesn't have shadows :O
and there is no entry in 3Ds material editor that prevent that and my placement xml file doesn't have No shadows entry !!!

any thoughts?
 
#52
Yes it does... through the Material Editor of 3ds Max.
in the SDK, it says "Uses the alpha channel to determine if the masked section should be visible or not, allows for anti-aliasing support on masked materials. You will still want to set a masked threshold to use for shadow support. " in the UseAlphaCoverage section, so must set a white alpha (cus my model is opaque) and set the masked threshold to 0.0 ?
 
#53
do you mean shadow is pre-define Ambient Occlusion? or Shadow generate in sim?
predefine shadow,
- prepare metalic texture at green channel have Ambient Occlusion/shadow.

- in material editor
1.jpg
 
#59
Hello all
i have a problem now
i made a SODE jetway with PBR materials
but the animation doesn't work
Is there any skinned mesh part that i missed? i looked in the SDK DOC and no mention about skinned mesh and PBR
 

Pyscen

Resource contributor
#60
@RED COOL

You would be better off going to the SODE sub-forum on this... since it has to do with the workings of SODE - and not what this topic is referring to.
 
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