5.5.1 adding alpha channels to all my existing textures that had none

The default in 5.5.1 seems to be to set input alpha source to "input texture alpha". Thus, textures with no alpha channel are suddenly adding one, taking up more memory and causing ETC2 vs ETC issues on Android.

Is this by design? Is it possibly related to "Graphics: Stopped the texture importer ignoring pure white Alpha channels by default. It is now a user option to choose to ignore it. (849356)"?

Also, the docs say the default is "none" for texture source, but this does not appear to be true. I can set it to none texture by texture to fix it, but obviously that's error-prone and a giant pain. I guess I could write some importer script to try to scan the alpha channel and set defaults sensibly, but it would be nice to avoid this. I think it's great that you can add a fully white alpha channel if you want to force it, but it seems like the default for a blank (or no) source alpha channel should be "none".

Am I just missing something?

 

We encountered same issue on 5.5.1.
When we upgraded to 5.5.1, Texture Import Setting set Alpha Source "Input Texture Alpha" by Default.
We hoped Upgrading to 5.5.1 not affecting the existing RGB Textures' import setting........now they are all RGBA(with Pure White Alpha)(Now they are all ETC2 on Android, which was set to ETC before)
We are probably going to have to go through all the textures with some importer setting script or manually to set Alpha Source "None"...

I'm wondering same thing as Skittlebrau
if this is user-error or not....or if this is occurring just on 5.5.1 because the Unity Manual says Alpha Source "None" by Default..

Thank you.

 

Hello. I have the same issue on 5.5.1 and ETC2 textures on Android. Its may be intresting that on iOS this textures converts to RGB pvrtc without alpha as i expect. So i think its a bug. Have you post one in issuetracker? Can you post case number here?

 

I did not submit a bug. I was hoping for some clarification of the intent. For now I have worked around the issue with a texture pre-process script that defaults the alpha source to "none" if the texture alpha channel is all white or all black.

 

I submitted a bug case - 881695

 

Its a duplicate for:
https://issuetracker.unity3d.com/is...o-rgba-even-when-texture-has-no-alpha-channel