Feedback Pixel perfect camera: a few questions.

I have a few questions about the pixel perfect camera component i recently found while fiddling with the unity editor. I'll start with just one as its the most confusing to me:

What do the green boxes mean and what is their relation to the Reference resolution?

For one thing, i dont exactly understand what it means by "Reference resolution". Reference in relation to what?
when attaching the pixel perfect camera component to the main camera, the actual, in-game camera is no longer the size of the white box of the camera, as i am used to, but rather a green box, which is only present when the pixel perfect camera is attached. Changing the reference resolution seems to have wildly different effects on the camera depending on the two values. For example, the defaults are 320 and 180, however, changing that 320 to 321 zooms the camera out drastically. However, setting x back to 320, and changing y to 200, zooms it out, but not nearly as much. Why is that? This component seems fun, but is very confusing.

 

bump cause i really wanna know.

 

bump

 

No, thank you. I didn't know where to find them. thanks very much although it doesnt seem to explain what the green lines are for. Oh well. I'll probably just have to mess around with it a bunch and try to guess what they are.