Reflection Probes vs. Screen-Space Reflections In Unity
There are often many reflective surfaces in games, especially games with highly realistic graphics. Here’s a brief look into the different methods to create them.
No Reflection Probes:
By default, without using any reflection probes and just making a smooth reflective material, the skybox will be reflected. While this is often perfectly fine for most games, high detail games may need more.
Reflection Probes are a feature in Unity which can create a sample of an area of the scene, then feed those images into the reflective material’s reflections. This creates quite nice looking and performant, though somewhat-inaccurate reflections.
A feature of Unity’s Post Processing, Screen-Space Reflections are a method to create visually-accurate reflections for surfaces. These reflections cost more in performance than the previous two methods, but are a great choice, and are arguably a necessity, for modern high graphical realism games.
Choose the method that best suits your project.
Generally, current mobile games don’t need Screen-Space (or possibly even Reflection Probe) reflections, while modern highly realistic games would probably need Screen-Space reflections to meet the standards of the rest of the game.