What is reflection in 2d?

Answer 1

My understanding of it is that everything displayed on a computer screen is in 2D. This is because your screen is flat. Rendering images in games is not as easy as filming real objects. The computer needs to know how to render objects in a way that gives the illusion of being 3D.

2D reflection in games is just a way of showing a second, often transparent, image of the original object, to the correct angle and shape, as the reflective object should show it.

Also 3D reflection is when one 3D rendered object is reflected off of another non-flat reflective 3D object. In this case the reflected image will need to bow and disfigure along with the curvatures of the new object.