How to optimize Lighting within a Scene
Lighting is a major part of Unity 3D infrastructure, but adding too many light sources will affect performance and optimization. Fortunately there is something called “Light Probes” which helps reduce processing power but also still provide proper lighting information throughout the scene.
Understanding Light Probes
Light probes are basically a giant mesh which provides a way to capture and store data about lighting when a object is passing through.
Referencing example 1, when a light hits and light probe that is on a white surface, the probe will store that it is white light. If the light hits an light probe that is on a Red surface, the light probe will understand that there is some red refracturing light and will store that data. When any moving object or player object is passing through these light probes, it will read the store data and display the correct lighting.
Creating the Light Probes Group
Adding the Lights probes is a very simple process. In the Hierarchy, right click and under “Light” select “Light Probe Group”. This will create a starting group of probes.
Once you have given the probe group a desired name, check out the Inspector. Each light probe group comes with an component of the same name. By selecting the “Edit Light Probes” you are able to manually add and adjust the position of the light probes.
Quick Tip: You can also select multiple Light probes at once by holding the “Shift” key.
What you want to do is to spend some time and assess where you might need a light probe and try to cover the entire scene as much as possible.