Really dumb question -- 3D printer without supports

I had a really random idea for a never-before heard of type of 3d printer (as fas as i know)

pretty much, it would shoot light into some sort of light-sensitive gel block to solidify it's print, so it doesn't need supports because the print would be suspended in a gel.

idk if this idea could go places, tell me why it shouldn't exist, and also why i might be onto something.