Apr 8, 2021
A Quick Look into Reflections in Unity: Probes vs SSR
If you have started working on the graphical side of your project, then you surely have come across Reflection Probes or SSR: Screen Space Reflections. These two technique add reflections to your scene and reflections usually increase the fidelity and realism of your scene.
Reflection Probes
A reflection probes almost acts like a camera that captures its surrounding in a spherical view and the captured image is set in a Cube Map. These cube maps will reflect on reflective surfaces in a defined area and probes can be placed around your scene. Reflection Probes do not give the best quality reflections, thus they are very efficient and useful for mobile projects.
How to set them up?
- Firstly, let’s create a reflective material and apply to a box.
2. Create a Reflection Probe: Create > Light > Reflection Probe and center it near the reflective box.
3. You can edit the captured are that is to be reflected by editing the Bounce Volume in the inspector of the reflection probe. (Almost like editing a collider)
Screen Space Reflection
According to Unity Docs “Screen Space Reflection is a technique for reusing screen space data to calculate reflections. It is commonly used to create more subtle reflections such as on wet floor surfaces or in puddles.”
In other words, it is way more detailed than reflection probes. The only disadvantage for SSR is that it is taxing on the performance and is not recommended for mobile projects.
How to set them up?
Firstly we need to create a Post Processing Profile in our scene in order to access SSR. (Please refer to this article to know how to set it up).
In the Post Processing Volume, add the Screen Space Reflection Effect.
Let’s see the difference with and without SSR.
To sum things up and in other words, if your project is a mobile game then just go with Reflection Probes, they are more efficient and require less resources. But if you want even more details in your reflections then use SSR.
