Reflection Probes vs. Screen Space Reflections in Unity

Objective: explore two ways to create reflections in a Unity scene.

The main ways to create reflective surfaces in Unity is either by using Reflection Probes or using a Screen Space Reflection in Post Processing.

First, lets take a look at Reflection Probes. We can create them in the same menu as a light probe group.

Here’s the scene before adding a reflection probe.

Here is the scene after adding a reflection probe. The boxed area shows which area of the scene should have reflective surfaces. This is very inexpensive for performance, which is good for mobile games. However, the detail and position of the reflections leave much to be desired.

The other way to create reflections is by using a post processing profile with Screen Space Reflection. We can activate it in the post-processing profile.

Here’s the scene with post-processing activated, but without the screen space reflection effect.

Now here’s the scene with screen space reflections. It looks absolutely beautiful! The downside is that these reflections take a decent amount of GPU time to calculate, so there will be performance issues on devices with integrated graphics cards, like mobile devices.

Both of these techniques have their place, based on whether the game is developed for PCs, consoles, or mobile devices.