The latter. Think an inkjet printer with uv-curable ink, and instead of paper it prints on anything you can put on its bed. They come with white ink, and usually varnish. You can make some relief with more quantity/layers of white and/or varnish. In industrial/professional shops is rare to see these ‘3d’ (also referred as 2.5d) effects, I only know one that prints high-end-ish pieces (for a big markup I guess) and one that specializes in prints for blind people so they use it for putting braille in lots of things, mainly for the time it takes (and I’m talking about professional machines) so most people do flat prints that are also pretty cool.
The latter. Think an inkjet printer with uv-curable ink, and instead of paper it prints on anything you can put on its bed. They come with white ink, and usually varnish. You can make some relief with more quantity/layers of white and/or varnish. In industrial/professional shops is rare to see these ‘3d’ (also referred as 2.5d) effects, I only know one that prints high-end-ish pieces (for a big markup I guess) and one that specializes in prints for blind people so they use it for putting braille in lots of things, mainly for the time it takes (and I’m talking about professional machines) so most people do flat prints that are also pretty cool.