Not sure if you guys have seen this yet but it's a pretty neat concept.
See here: https://www.velocitypainting.xyz/blog/
It's software the modifies the g code to change the speed of the printer real time in order to make a pattern on a print. I downloaded the vase and pattern that he had and printed it in some translucent green PETG. It came out awesome. Unfortunately it doesn't hold water but I could spray it with some sealant. I'm going to use this for several different patterns and projects in the future.
Here's a pic of my vase:
Velocity Printing
Re: Velocity Printing
Yeah, that's pretty cool.