The whole camera-capture pipeline (a la ARFrame capturedImage).
ARKit stiches up environment texures for you (based on the series of recenter camera images).
For custom renderers:
ARMatteGenerator helps Metal apps draw person segmentation.
Camera grain textures helps Metal app's virtual content blend more with the camera feed.
(edited 4/20/20 to provide links)
Thank you for the quick respons. Very kind of you to answer.
I think you put me on the correct track :-)
I surmised that it was being used similar to the usage of a convenience function.
'A convenience function is a non-essential subroutine in a programming library or framework which is intended to ease commonly performed tasks."
Thank you for taking the time to answer
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