This can be used to fade lights and their shadows in the distance,
similar to Decal nodes. This can bring significant performance
improvements, especially for lights with shadows enabled and when
using higher-than-default shadow quality settings.
While lights can be smoothly faded out over distance, shadows are
currently "all or nothing" since per-light shadow color is no longer
customizable in the Vulkan renderer. This may result in noticeable
pop-in when leaving the shadow cutoff distance, but depending on the
scene, it may not always be that noticeable.
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