[jetbooster]

Isn't determining lighting without some reference card a "hard" problem? How do you tell the difference between a yellowish room illuminated by white (sunlight) versus a whitish room illuminated by warmer yellower bulbs?

I am a not a photography person so this a genuine question asked from ignorance

[hitmyapi]

Yup that's a great question, I think generally speaking that is a really difficult problem in the AR space, which I think is part of the reason why most AR models still look fake or have the uncanny valley.

Using the ARKit libraries, it gets handled automatically for the most part. I think there's a lot of computer vision/image processing algorithms running in the background that potentially pick up on shadows/reflections in real world objects, which help it determine the white balance/color temperature of the room. I'm no expert on it myself though and not 100% sure on the science behind it