Naw. This is probably more what you’re after
https://www.construct.net/en/tutorials/enlighten-games-dynamic-1213/normal-maps-5
There was a more recent normal map effect, but I was didn’t look too hard. It’s made by user Everade.
Oh my goodness I didn't even think of normal maps. O_O All this time I thought it could be a sprite's shape being altered. Thank you so much! : )