I believe Microsoft already has this built into the OS these days:
https://learn.microsoft.com/en-us/microsoft-edge/devtools/ac...
Of course shader glass will let you write your own, custom, possibly more-realistic colour blindness simulations, but you don't necessarily need third party tools for that kind of thing these days.
I've tried making similar functionality in Python to add visual effects to the screen, but the only way I found is to use one of the packages which leverage the Screenshot functionality.
But this causes recursion since my app's window will be in the screenshot (unless I put my app on a different monitor or a different area of the monitor). How do they avoid that?
And also, I read it talks to #device capture input (webcam/capture card)#
Can't cheater providers use this to inject colors?
I also wonder how many could be ported to run in the browser for games.