I’ve actually been looking into doing , but I would like to have the drops running down the screen (from it raining outside, ect)
I found a cool tutorial on how to do the normal maps for the drops in photoshop. I am yet to find out how to make the drops animate however. But check out tutorial. Im going to mess around tonight and see if I cant make work in Gimp or PDN since those are the only programs I use for image editing.