UE4 already uses GGX. If you want to modify something, you should do it BRDF.usf and/or ShadingModels.usf files.
There is also fresnel material expression that you can use in the editor.
UE4 already uses GGX. If you want to modify something, you should do it BRDF.usf and/or ShadingModels.usf files.
There is also fresnel material expression that you can use in the editor.