GI cache

The GI cache is used by the Global Illumination (GI) system to store intermediate files when precomputing real-time GI, and when baking Static LightmapsA pre-rendered texture that contains the effects of light sources on static objects in the scene. Lightmaps are overlaid on top of scene geometry to create the effect of lighting. More info
See in Glossary, Light ProbesLight probes store information about how light passes through space in your scene. A collection of light probes arranged within a given space can improve lighting on moving objects and static LOD scenery within that space. More info
See in Glossary and Reflection ProbesA rendering component that captures a spherical view of its surroundings in all directions, rather like a camera. The captured image is then stored as a Cubemap that can be used by objects with reflective materials. More info
See in Glossary. The cache is shared between all Unity projects on the computer, so projects with the same content and same version of the lighting system (Enlighten) can share the files and speed up subsequent builds.

You can manage the size, location, and compressionA method of storing data that reduces the amount of storage space it requires. See Texture Compression3D Graphics hardware requires Textures to be compressed in specialised formats which are optimized for fast Texture sampling. More info
See in Glossary, Animation CompressionThe method of compressing animation data to significantly reduce file sizes without causing a noticable reduction in motion quality. Animation compression is a trade off between saving on memory and image quality. More info
See in Glossary, Audio Compression, Build Compression.
See in Glossary of the cache using the GI Cache preferences. For more information, see the Preferences documentation.

GI cache and lighting

To ensure that the the lighting data loads from the GI cache in a very short amount of time when you reload your Scene, open the Lighting window (menu: Window > Lighting) and enable the Auto option next to the build button. This makes lightmap baking automatic, meaning that the lightmap data is stored in the GI cache.

In the Lighting window, you can clear the baked data in a SceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary (disable the Auto option and choose Clear Baked Data from the BuildThe process of compiling your Project into a format that is ready to run on a specific platform or platforms. More info
See in Glossary button drop-down menu). This does not clear the GI Cache, because this would increase bake time afterwards.

You can share the GiCache folder among different machines. This can make your lighting build faster, because the files are downloaded from the GiCache folder instead of computed locally. Note that the build process isn’t optimized for slow network-attached storage (NAS), so test if your bake times are severely affected before moving the cache to NAS.