09. Global Illumination
After the Environment section, we will start to dive deeper into the core of how we can optimize our lighting! These next 3 sections in the Scene tab fall under what Unity calls the Global Illumination.
Global Illumination (GI) is Unity’s system to model complex lighting such as indirect light that bounces off nearby objects. It works really well with Unity’s Standard Default Material to really bring our scenes to life! These four sections are:
- Realtime Lighting
- Mixed Lighting
- Lightmapping Settings
They let us fully control the parameters Unity uses when it makes it calculations for pre-computed lighting.
The first section is Realtime Lighting
If you added real-time lights in your scene, you could use this section to enable precomputation of some lighting effects for static objects in your scene. If you enable Realtime Lighting, you will see that you will have the option to change the Ambient Mode in Environment Settings and the Indirect Resolution in the Lightmapping Settings.
Basically, Precomputed Realtime GI calculates how light could bounce off a static object (indirect light) and can then use that information in realtime for moving objects when you start your application.
Since we we don’t have any real time lights in our Apartment scene, we can leave our Realtime Lighting disabled.
Next up, let’s talk about Mixed Lighting and Lightmapping Settings, so we can get the most performance from baking.
