I was wondering how I could go about creating a vignette type effect / some sort of volumetric shadow for the 'cross section' parts of a 2.5D level. The effect I'm going for can be seen in 'This war of mine' where the edges of the rooms and walls / floors that are facing the camera have been darkened and blurred. (see below).
I thought about creating the edges in photoshop and then blurring them and putting them in, however the blur scales weirdly as I'm re scaling the sprites so it looks really fake and not like a visual effect. Is there perhaps a 2d shader I could use or make?
Any help on this would be appreciated!