@aeva@demofox@dotstdy@jon_valdes There's lots of versions of CPU sin/cos as well. The fastest is basically identical to the GPU one - about 12 bits of precision, IIRC. Then they do iteration internally if you want higher precision. There's no magic - everything costs!
As you noticed, sometimes it's better not to call sin-vs-cos, because you're not guaranteed to get magnitude 1.0. In those cases it's better to get sin and derive the other by doing sqrt(1-sin^2).
@francina1909 dipende dal carattere del gatto. Ma se tu sei tranquilla e coccolosa ci sono buone possibilità che lo sia anche il felino infame che ti userà come cuccia e dispensa crocchette...