Final image from my “Ray Tracing in One Weekend” implementation in Swift (took ~1 hr to render @ 800x600x16 samp/px)pic.twitter.com/2IiiXz6K00
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It's been a while, but I think my recursion limits were insane. Also, that banding is due to numerical issues I later fixed.
Oh ok I see! I would be curious to see how fast it would be with Metal kernels! BTW, your MBE book is great and really helpful! 
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