The Vertex Alpha is used to manage the spread of icing on the windshield.
The Vertex Red masks the Red channel of the ‘Details Scratch(R), Icing Mask(G), Fingerprints(B)’ texture.
The Vertex Green masks the Alpha channel of the ‘Secondary Details(A)’ texture.
The Vertex Blue masks the Blue channel of the ‘Details Scratch(R), Icing Mask(G), Fingerprints(B)’ texture.
Regarding the Secondary Details, it’s used to make the windshield more opaque. Only the Alpha channel is used in this case. It is not related to the icing
We will update the documentation, as these subsections should not be under 'Icing Normal and add more information.
Icing mask(G) is still in the label. I know it is mentioned that it’s really Dirt. It’s a label, why can’t it be changed in 3DS and Blender exporters to Dirt. Or just make the label
It appears that the Icing Mask (G) is correctly named, contrary to what the documentation suggests; I think it is not misnamed.
To summarize this:
There are two aspects to consider: Texture Channels and Vertex Color.
In the ‘Details Scratch (R), Icing Mask (G), Fingerprints (B)’ texture:
The R channel of the texture represents Details Scratch.
The G channel of the texture is for the Icing Mask.
The B channel of the texture denotes Fingerprints.
(Note: The ‘(R), (G), (B)’ in the texture’s name refers to the channels of the texture, not to Vertex Color.)
The Vertex Color, on the other hand, acts as masks on different textures depending on the channel:
The R channel of Vertex Color affects Details Scratch.
The G channel of Vertex Color is for Secondary Details (dirt).
The B channel of Vertex Color applies to Fingerprints.
The A channel of Vertex Color is used for the Icing Mask
In testing your explanation, it appears that you are indeed correct. The SIF (Scratches, Icing, Fingerprints) is NOT Dirt. It is related to icing.
The Icing normal is also icing and the SA (Secondary Alpha) is NOT icing related.
So the documentation is very confusing and misleading and wrong.
The pics show the three texture I used in my test with channel identifiers
SIF-R Scratches, Icing, Fingerprints Red Channel Scratches
SIF-G Scratches, Icing, Fingerprints Green Channel Icing - Only shows with icing on
SIF-B Scratches, Icing, Fingerprints Blue Channel Fingerprints
SA-A Secondary Alpha (Dirt?? or something that shows on the windshield)
F DET N (Icing Normal) , - I guess Icing heightmap like- shows with icing
The 152 also has textures for the OMR slot a comp map. This is NOT explained in the documentation.
I was also able to “tint” the windshield by using a basecolor factor (not texture) - works again not explained in the documentation. I found a 152 texture named CESSA152_AIRFRAME_WINDSHIELD_ALBD.PNG
but was unable to link it to the windshield in my analysis of the 152, It seems to be linked to the fuselage and NOT the windshield.
Can you elaborate on how that is used.
Vertex Alpha Painting (Blender speak is Erase Alpha/Add Alpha) works also.
I have not tested Vertex Color Painting as that is not an option available yet in the ASOBO blender exporter. I do have my own experimental Exporter that handles Vertex Alpha and Vertex Color
Vertex colours work fine in blender and with the exporter. You will probably want to create a custom material with a custom shader node tree just to visualise the alpha while you’re painting though (switching back to your windshield material when you’re done).
