I’m making an attempt to pack my Ambient Occlusion, Metallic, Roughness, and Height maps into the RGBA channels. I can get the RGB channels to work as intended, but I don’t get any colors from the Alpha channel. It’s just black. I’ve tried plugging it into mix and color ramp nodes, and even tried playing around with the blend modes, but so far, no dice.
I figured it should be possible, since A is just another greyscale channel when you get right down to it, but I can’t seem to get it to work. Can I get this to work?
Hello, could you please show your Shader Editor? The alpha is supposed to be plugged into the Alpha input of the Principled BSDF but I’m not sure to completely understand your situation
Here’s what I’m doing, in case you’re wondering. I’ve got three textures in my material, the diffuse, normal, and the AO/Roughness/Metallic/Height texture.
There’s more than one correct way to pack textures into channels- what you’re describing is a typical PBR setup, but what Renzatic is describing is more similar to an ILM map
It’s pretty common for game engines, since it doesn’t have quite as many separate textures potentially eating up your VRAM. I think Quixel Megascan assets like to default to a packed Occlusion/Roughness/Displacement (ORD for short) texture setup for UE.
I’m using it mostly because it’s fewer textures, and thus fewer nodes to deal with.
Just to toss something into the mix…I use it when dealing with many game engines. It has really saved resources.
In this example…just a quick dirty Diffuse to the R channel, Roughness to Green, and a Bump Map to Blue… Baked the maps and imported them to the compositor to pack them…( usually done in an external program)…but Blender can produce some FINE results…
Monkey Material to single RGB .PNG file…
Very rarely would you do this. You don’t get a 1/1 image, (it is because I first took the rendered image and separated it to Values of RGB…so when placed in the R channel ( Red means nothing in this concept) it Maps all the RGB values to Color) …but it is really close and I just used it as an example of what you CAN do.
Many games now are taking this concept and setting the packed image texture to do everything but the color/diffuse…they do this so that in the engine you have 1 texture for everything and an RGB node to add the color… which gives you thousands of possibilities for Factions and the like…I know that Eve -online has switched to this as they spent some time baking all the PBR textures down to do it…
