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Nice to read this.

Curious how CORDIC performs against cubic or other polynomial interpolation with a small table. I was taught that resource constrained synthesizers sometimes used cubic interpolation, and this was presumably when CORDIC was relatively new.

At a glance, the single bit of precision you get with each iteration of CORDIC means it would be more expensive in compute but cheaper in space than a polynomial.

But on the space note I feel we should highlight that it can be cheaper than the article might suggest with the 4096 entry lookup tables for sin(x) - Only a quarter of the full circle is needed due to symmetry.



Back in the day gamedevs (and demosceners) used a merely 256-entry LUT for sin and cos – it was convenient to have byte-sized angles that auto-wraparound, and for rotation in 2D games, 2^8 was quite enough. Wouldn’t get you very far in 3D though if you want smooth motion.




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