PBR maps for Godot 3...where is the metalness map slot?

zendorf

I am playing around with the new PBR shading in Godot 3. I am quite new to the PBR workflow and have exported the standard maps from Substance Painter for a model. Inside Godot 3, I have the albedo, roughness and normal maps inserted into the corresponding map slots fine.

Where I am confused is the metalness map, as there is no map slot for metalness in Godot, only a color and value slider. How does a Godot material get metalness information? Maybe I have to combine it into the alpha of the roughness...I seem to remember Unity has something strange like that.

If anyone has worked this, please let me know!

Calinou

Godot currently does not support having metalness maps as separate images (even though this is the most common workflow). You may want to create an issue for this.

zendorf

Thanks for your reply. From a test I did using maps from Substance Painter, it seems to be using the same method as Unity. This puts the greyscale metalness map into the alpha channel of the roughness map. It looks more or less correct to me, but it did require overcranking the metalness parameter to 10 (even though it still only shows as 1 in the IDE).

I was going to create an issue on Github but was unsure how reduz intended it to work? Having a separate map slot would be a good option, but it is also nice to stick 2 maps in one for practical reasons. Unity also puts the transparency map into the alpha of the albedo map. Do you know any more info about any of this? As a developer, maybe you can ask reduz?