Lightmap Snapshot was renamed to Lighting Data Asset in Unity 5.3.
You generate the Lighting Data Asset by pressing the Build button in the Lighting window. Your lighting will be loaded from that asset when you reload the scene.
The Lighting Data Asset contains the GI data and all the supporting files needed when creating the lighting for a scene. The asset references the renderers, the realtime lightmaps, the baked lightmaps, light probes, reflection probes and some additional data that describes how they fit together. This also includes all the Enlighten data needed to update the realtime global illumination in the Player. The asset is an Editor only construct so far, so you can’t access it in the player. When you change the scene, for instance by breaking a prefab connection on a lightmap static object, the asset data will get out of date and has to be rebuilt.
Currently, this file is a bit bloated as it contains data for multiple platforms - we will fix this. Also we are considering adding some compression for this data.
The intermediate files that are generated during the lighting build process, but is not needed for generating a Player build is not part of the asset, they are stored in the GI Cache instead.
The build time for the Lighting Data Asset can vary. If your GI Cache is fully populated i.e. you have done a bake on the machine before (with the scene in its current state) it will be fast. If you are pulling the scene to a machine with a blank cache or the cache data needed has been removed due to the cache size limit, the cache will have to be populated with the intermediate files first which requires the precompute and bake processes to run. These steps can take some time.
Did you find this page useful? Please give it a rating:
Thanks for rating this page!
What kind of problem would you like to report?
Is something described here not working as you expect it to? It might be a Known Issue. Please check with the Issue Tracker at issuetracker.unity3d.com.
Thanks for letting us know! This page has been marked for review based on your feedback.
If you have time, you can provide more information to help us fix the problem faster.
Provide more information
You've told us this page needs code samples. If you'd like to help us further, you could provide a code sample, or tell us about what kind of code sample you'd like to see:
You've told us there are code samples on this page which don't work. If you know how to fix it, or have something better we could use instead, please let us know:
You've told us there is information missing from this page. Please tell us more about what's missing:
You've told us there is incorrect information on this page. If you know what we should change to make it correct, please tell us:
You've told us this page has unclear or confusing information. Please tell us more about what you found unclear or confusing, or let us know how we could make it clearer:
You've told us there is a spelling or grammar error on this page. Please tell us what's wrong:
You've told us this page has a problem. Please tell us more about what's wrong:
Thanks for helping to make the Unity documentation better!
When you visit any website, it may store or retrieve information on your browser, mostly in the form of cookies. This information might be about you, your preferences or your device and is mostly used to make the site work as you expect it to. The information does not usually directly identify you, but it can give you a more personalized web experience. Because we respect your right to privacy, you can choose not to allow some types of cookies. Click on the different category headings to find out more and change our default settings. However, blocking some types of cookies may impact your experience of the site and the services we are able to offer.
More information
These cookies enable the website to provide enhanced functionality and personalisation. They may be set by us or by third party providers whose services we have added to our pages. If you do not allow these cookies then some or all of these services may not function properly.
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
These cookies may be set through our site by our advertising partners. They may be used by those companies to build a profile of your interests and show you relevant adverts on other sites. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. If you do not allow these cookies, you will experience less targeted advertising. Some 3rd party video providers do not allow video views without targeting cookies. If you are experiencing difficulty viewing a video, you will need to set your cookie preferences for targeting to yes if you wish to view videos from these providers. Unity does not control this.
These cookies are necessary for the website to function and cannot be switched off in our systems. They are usually only set in response to actions made by you which amount to a request for services, such as setting your privacy preferences, logging in or filling in forms. You can set your browser to block or alert you about these cookies, but some parts of the site will not then work. These cookies do not store any personally identifiable information.