P3D v4 What are the settings to make specular alpha channel works?

Hi,

I would like to make my GP to shine with my specular map. But when i tried to change the darkness of alpha (Black to white/grayscale), it seems doesn't make any change. So, can someone guide me what should be the settings of material in MCX to make the specular alpha works?
 

Pyscen

Resource contributor
Hello Manochvarm...

There are 2 slots under "Special Functionality" that need to be set to "true" if you are using the alpha channel of the Specular Map
Blend diffuse by inverse specular alpha
Blend environment by specular alpha

These 2 slots should use the specular map's alpha channel to be reflective of it surroundings

May I ask the reason why the specular map and not the diffuse map's alpha channel?
 
Hi Pyscen,

I am trying to make my runway texture have some reflection on rainy day. Diffuse map’s alpha makes the reflection too strong. Even after try reducing the reflection scale, I don’t get the desired reflection that I needed with that. So I am trying to reduce the reflection using specular map alpha.
 

Pyscen

Resource contributor
Well...

The diffuse's alpha channel would translate the same as the specular's alpha channel, just using a different alpha channel.

The color base used within the specular map is what will reflect from the sun... the alpha channel of it will determine the strength of the reflection of the environment map. It would be the same as if the diffuse's alpha channel was used.

What I mean by the strength of is: how sharp the reflection is of the environment map.

Keep in mind though... the alpha channel will also affect the transparency of either the diffuse base color and or the specular base color depending on which you use.

The diffuse's alpha channel is easier in terms when it comes to the environment map. You still can use the specular map though to show the reflection of the sun.

Hope that makes sense.
 
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Well...

The diffuse's alpha channel would translate the same as the specular's alpha channel, just using a different alpha channel.

The color base used within the specular map is what will reflect from the sun... the alpha channel of it will determine the strength of the reflection of the environment map. It would be the same as if the diffuse's alpha channel was used.

What I mean by the strength of is: how sharp the reflection is of the environment map.

Hope that makes sense.
It is something interesting for me. Can you explain more about it to me?

Situation 1:
Let say i am using diffuse alpha for the reflection, what will this be the MCX setting?

Situation 2:
For specular map alpha, do you mean that, let say we use yellow colour as the base specular map and has an light grey alpha, then it will reflect yellow colour on the ground when there is sunlight?

Hope you can clarify me this.

Thank you.
 

Pyscen

Resource contributor
Hello...

Sorry in getting back to you late... my modem /router decided to malfunction and will not be replaced until later this day..... but I will try to answer you the best I can.

Situation 1:

If the diffuse's alpha is being used:.

The 2 slots in MCX that would need to be set to "true" under the area: Special Functionality are:
"Blend diffuse by diffuse alpha"
"Blend environment by inverse diffuse alpha"

If the diffuse base was chrome or grey... and the alpha was light grey... the alpha would blend the environment by the "inverse" color of the diffuse's alpha

Situation 2:
If the base color in the specular map is: yellow and the alpha: light grey.... then yes the sun reflection would show a yellow hue. Keep in mind though it would show transparent because of the alpha being light grey. The alpha being a light grey would be "inversed" to blend the environment map.

The diffuse option is easier to predict.... because the specular being transparent due to the alpha.... if you follow me.

I think that covers it...
 
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