Question Roughness and AO maps for HDRP

I've upgraded my project to HDRP, but I'm having trouble finding where to put my AO and roughness maps. I've read something about using various channels of the mask map, but I have no idea what that means. I don't see any channels for the mask map. I just see a space where I'm supposed to put my texture.

If I put either my AO or roughness texture in there, the material simply goes black. Also, how am I supposed to use both roughness and AO maps on one slot? Can anyone tell me what I'm doing wrong? Any help is appreciated.

 

HDRP lit material uses a mask map, where the Red, Green, Blue & alpha channel represent the following:

• Red (R) = Metallic (white is 100% metallic, black = 0% metallic)
• Green (G) = Ambient occlusion
• Blue (B) = detail map mask (masks in the detail map)
• Alpha = glossiness

Hope this helps. Mask map is much better than individual maps for metallic, AO & glossiness, because it takes up less memory and has quicker access for rendering engine / hardware (access one map instead of 3)

 

I appreciate you trying, but I have no idea how to implement what you are telling me based on the screenshots I uploaded. I have multiple textures (AO and roughness) and one mask map slot. Where do the RGBA channels come into it? I don't see any RGBA channels, nor do I have any idea how to apply maps to them. What am I missing?

 

And each texture has multiple channels. Red, Green, Blue and Alpha (If you're using .png, for instance). Therefore you can put up to four grayscale maps (one per channel) in a single texture.

 

Yes, I get that. But I'm not sure how to make use of those channels in Unity. How do I put those textures into each channel? I don't even see those channels within Unity.

Are you saying I need to put those textures into each channel within an image editing program?

 

Yes. Unity has nothing to do with this process. The shader you're talking about just expects this kind of packing within a texture. How this packing is done - is up to you. There are numerous third-party assets and scripts that can help you with that. Can't recommend anything in particular, just try searching "texture packing" on the asset store or in Google and pick what looks best for you. Personally I use some free script I stumbled upon on reddit long time ago. If you're more familiar with Photoshop - you can just do it there as well.

 

Ah, I see. That makes more sense. Appreciate the help.

 

@Clydey2Times Try these
https://github.com/andydbc/unity-texture-packer
https://github.com/razluta/UnityTextureRgbPacker

There's should be other similar tools in github. Also afaik Material Converter should be able to help generate that texture from an existing material as long as it is using Builtin Standard