Yeah A:I had 100% dynamic lighting (well, maybe like 99% as there were some extremely huge exterior sections which we had to lightmap but they were very small proportion of the game). We used method whereby decals have 8-bit alpha mask and directly overwrite value in the gbuffer for that pixel - so we had decals which only…
I am not sure how blending with the underlying surface works in your UE4 shader (i.e. whether it's an opaque shader that does no alpha blending and just outputs a result duplicating the underlying surface for areas with "One around the button" material; or whether you're doing proper alpha blending that requires no…