We used to have that before, but it was hardcoded and depended on
mobile vs. desktop.
With this change, users can set the quality on the material itself.
The default match the current settings. There are 3 quality levels:
low: enables optimization that might not be 100% correct
(e.g. abs(x) instead of sqrt(x*x))
normal: like low, but doesn't sacrifices correctness.
high: could be improved upsampling, etc...
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