I want to implement a colour catalogue (for paint selection, but this hardly matters). I have RGB (or any other colour space you like) in my spreadsheet; now I need to be able to use it to make a swatch in my application view. A few things would work, for example control of foreground/background for text elements, or a pseudo- image type that consists of just an RGB code (this latter seems more clunky, but leaves the door open for things like computed gradients, which would be a useful enhancement).
What I don’t want to have to do is make sixteen million pngs, or rely on an external image generator (although of course these exist, and could be used for prototyping).
Use Cloudinary! Find a white square image online, fetch it and then colorize it using a hex code.
Eg.
https://res.cloudinary.com/YOURUSERNAME/image/fetch/e_colorize,co_rgb:HEXCODE/LINKTOSQUAREIMAGE.png
For a formula, given that the hex codes are in Column A:
ARRAYFORMULA("https://res.cloudinary.com/YOURUSERNAME/image/fetch/e_colorize,co_rgb:"&A2:A&"/LINKTOSQUAREIMAGE.png")