How to BP on-screen indication of off-screen possible collisions?

Hi. I’m working on a vertical sidescroller that increases speed over time and I believe it will be quite hard for the player to dodge incoming objects based on reaction alone at high speeds. I’d like to build in some kind of screen border warning system that will add a little clairvoyance to the player; in the form of a red haze that matches pixel for pixel where the object is and how large it is.

crappy example I drew: (imagine those left and right pillars are repeated above, off screen)

So let’s just start with the basics, because I’m a novice and I really don’t understand how this type of thing is implemented. Could someone breakdown how it might be possible, and suggest some BP blocks to start with?

Thanks

Has anyone tried this before?

This might be what you need:

It’s a custom BP node made pretty much for this purpose.