Texture Pack Substance Designer to Unreal Engine

Devon M

Hello all. So I'm trying to figure out how to texture pack correctly in Substance Designer so that I can use a combined rgb map (roughness, metallic, and AO) inside my project in Unreal Engine. 

I did some research and found that the RGBA Merge node is perfect for this. However, I don't think I'm using it correctly inside Substance Designer. Here is a screenshot of that.

Some preface before the screen shot: The Diffuse and Normal map are plugged into their own, separate outputs. I have the RGBA Merge node connected in 1 output that can read the rgba values.

http://puu.sh/rs445/3960eec308.jpg

I'm doing something wrong because in my 3D viewer it's acting as if I don't have any roughness, metallic, or AO plugged in. 

So I thought I'd attach each channel (roughness, metallic, and AO) into their own separate outputs, but come from the same node (the RGBA Merge.) Here is a screenshot of this:

http://puu.sh/rs4eO/6a45a581fb.jpg

Technically, this works. However, the problem I then run into is this: When I import this Substance into my Unreal project, it imports that RGBA map three times (one for roughness, one for metallic, and one for AO.) Screenshot below:

http://puu.sh/rs4kh/3913686de0.jpg

If I try to use one of those RGBA maps, Unreal acts as if nothing is there and only my diffuse/normal get through. 

In the end, I need to have the following maps: Diffuse, Normal, and RGB (packed with roughness, metallic, and AO). What am I doing wrong?

Thanks in advance.

Froyok

The 3D view can't be aware of your packing, more precisely the shader used by default doesn't know what you are trying to achieve with your graph. You need a custom shader to tell the 3D View to unpack your packed channels and tell which channel is what (metallic, roughness and so on).

Also for UE4 you need a BaseColor, not a Diffuse output.

Devon M

@Froyok Thanks for the reply. 

Okay, well that's good to know about the 3D View. And forgive me, I meant BaseColor. 

Do you have a suggestion on how to use the mentioned node (above) correctly? I feel like I'm doing it wrong based on all the screenshots/information I provided. I really don't want to have to save out each individual map, go into Photoshop and pack it there, and then export those into Unreal. Surely there's a way to correctly do it within Substance Designer?

Thanks for all the help. 

Froyok

You can create as many output nodes as you need. So simply create the output for the regular textures, and add a new one for you combined textures (the merge node). This way you can visualize in the 3D view the result of your material and also export a packed texture for UE4.