First time posting here. I'm working on a mouse-and-keyboard disability device for a course bioengineering course and I've got a feature that I've got no clue how to begin implementing. Basically, I want to be able to "select" which are the K "focus targets" nearest to the cursor, draw boxes around them/highlight them (much like Chrome or Windows does) and, after deciding which "target" I want to select, focus/click that one. The goal is to use eye-tracking software to move a cursor and then blink/contract a muscle to see which are the closest targets (that way you can click on really tiny stuff which would be hard to select otherwise).

Not sure if "focus target" is the right word, I mean "what gets selected next" after you press Tab. If there's some "universal" way of doing this across apps that'd be great, but either a browser-only or Windows-only way would be great. The only workaround idea I've had so far is to press Tab a bunch of times, see what changes appear on screen, use OpenCV to detect on-screen changes and then see which are closest to the cursor, but that means the screen would spaz out and also wouldn't work if there's any sort of animation on the screen.

Thanks in advance!