What does the Alpha channel in the Normal maps do ?

[-=[]=-little-Guardian]

 

As the title says . . .

 

I noticed that the original Normal Maps have an alpha channel with some black and grey areas, while the new ones in 4K mostly have an empty (plain white) Alpha channel.

So, what exactly does the original one do? Damage, like holes in the fuselage or wings where you can see through . . . ?

 

The "glossiness" is already in the Alpha channel of the main skin template . . .

 

Thanks a lot for helping

 

the little Guardian

[BlackHellHound1]

Any 4K normal map with a blank alpha channel is missing a key part of the damage model. 

 

The Normal map's Alpha channel is used to display the black "hole" in a bullet hole and works together with the main damage file. Not all the holes on a plane are displayed by a real hole. The internal model is simply not detailed enough for it to look good so instead of making it a real hole you can look through, it simply has a black "hole replacement" there. 

The grey parts and such are used to display leaks caused by damage etc. (once again in combination with the main damage file)

 

If a normal map misses the Alpha channel, then the plane will not display these black "hole replacements" and leaks due to damage. It is a key part of the damage model and all template makers should add it to their templates. (provided the original 2K also has them)

 

BlackHellHound1

 

[-=[]=-little-Guardian]

Thank you BlackHellhound1.   Wow. that was quick and helpful

 

So now I have to check all the normal maps to be sure the alpha is correct (and my planes are no longer bullet proof)

 

 

Cheers    the little Guardian

[Raptorattacker]

To be fair, most makers of templates will put the damage Alpha on the normal maps. In my time of working with templates I've only come across two. It's a bit of a pain checking them but realistically should only take you 5-10 minutes tops. 

Rap 

[Zargos]

When I made my first 4k template and normal map, I totally missed the alpha channel !

Now then, I use the default 2k normal alpha layer and convert it in 4k.

 

What I don't know is if I can modify the noraml alpha layer to change the damage model ... any idea guys ?

Edited August 3, 2018 by Zargos

[BlackHellHound1]

11 minutes ago, Zargos said:

What I don't know is if I can modify the noraml alpha layer to change the damage model ... any idea guys ?

 

Not that easily. There is the main damage file separate from the normal map that is used to display the majority of the damage pattern. Only the black "hole replacements" and the colouring for the oil leaks are shown on the Alpha channel of the normal map. So... it is a small part in a larger system. 

 

You can change the damage model (which I did for the 4k IL-2 1943) but this will require you to completely redo the damage model file and the alpha channel on the normal map. (although there are some restrictions based on break lines.

 

BlackHellHound1

 

[Zargos]

Oh my God !

Too much work ! I give up ...

[LizLemon]

Not all planes have any damage on the alpha layer on the normal. The 111 H6 for instance. It might be worth adding some damage to that one and see what happens.

[-=[]=-little-Guardian]

Interesting, mine has (the he111h6) I checked and it is identical to the he111h16.

The same goes for the original normalmaps in the game in 2K, they are exactly the same . . .   as far as I can tell

 

little Guardian

 

[Skipper-]

On 8/3/2018 at 2:51 PM, BlackHellHound1 said:

There is the main damage file separate from the normal map that is used to display the majority of the damage pattern. Only the black "hole replacements" and the colouring for the oil leaks are shown on the Alpha channel of the normal map. 

 

Is it possible to look into damage holes in the wings and see the ribs in every plane?

I was amazed the first time I could see the ground through a hole in my wing in the IL-2 1943 but I haven't seen through holes yet in the Spitfire, only the solid black bullet holes from the normal alpha.

[BlackHellHound1]

22 minutes ago, Skipper- said:

 

Is it possible to look into damage holes in the wings and see the ribs in every plane?

I was amazed the first time I could see the ground through a hole in my wing in the IL-2 1943 but I haven't seen through holes yet in the Spitfire, only the solid black bullet holes from the normal alpha.

 

I haven't checked it but I think all planes have holes that show the internals of the plane.

However, it depends mostly on how damaged a section on your plane is and if the holes are aligned. There are 3 damage levels (light, medium and heavy). On most planes, only the medium (mostly small holes)  and heavy (mostly large holes) will show real holes. 

If your plane hasn't taken enough damage, you won't see the medium and heavy damage and thus no holes.

 

BlackHellHound1