Light probe performance impact

Hi!

Just had a quick question regarding the performance impact of light probes.

I have a large scene with many apartments, but I’ve yet to add any light probes. The scene is pushing the limit with regards to overall size and (therefore) hardware needed to make it run in a browser.

Will adding light probes make the scene even more computationally expensive?

Side note: Can light probes be added post-baking (does bake and light probes affect each other)?

A single light probe uses about 7MB of GPU memory and takes upto 1s to be generated when the scene is loaded. On mobile devices with limited memory too many light probes can cause the scene load failure, although from our experience too large geometry or too many lightmaps are more often the cause of such failures.

If your scene is already large, it is better to limit the number of lighprobes and put them only in key rooms with important reflective materials. Lightprobes do not affect the look of materials with roughness 1.0.

Lightprobes can be added post-baking. Lightprobes are always generated at runtime after the scene is loaded, they are not stored, it doesn’t matter in which order you configure them.

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