Author Topic: UE4 plugin doesn't respect Usage per channel on packed textures  (Read 908 times)

I created a packed texture output in Substance Designer and specified Usage components for each channel in the output node. However, when I create a UE4 material from this file, the UE4 Substance plugin doesn't wire up the packed texture correctly.

The Substance UE4 plugin code (CreateMaterialExpression in SubstanceCoreHelpers.cpp) indicates that only the default channel is considered when wiring textures up to output nodes. The default channel appears to be the first Usage component configured on the output node in Designer. I confirmed this by switching the Usage setting on a couple of components.

Steps to Repro:

1. Create a packed texture in Substance Designer
2. Setup the usage components on the output node for the R, G, B, and A channels.
3. Import into UE4.
4. Create a UE4 material from this Substance file.
5. Open the UE4 material.

Notice the material isn't wired up correctly.