SDL_acosf(3)

💖 SDL_acosf 💖

okay bestie, welcome to the SDL3 FUNCTIONS corner of the manual, where we're talking about SDL_acosf — compute the arc cosine of x. yes queen, we're doing trigonometry and we're doing it cutely. ✨

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🌸 SYNOPSIS 🌸

#include <SDL3/SDL_stdinc.h>

float SDL_acosf(float x);

that's it. that's the whole vibe. one include, one function, one float going in and one float coming out. 🎀

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🦋 DESCRIPTION 🦋

so like, the definition of y = acos(x) is x = cos(y). that's the whole tea, that's the whole relationship. they're inverses of each other, they're giving soulmate energy fr fr. 💅

here's the deets on what you can actually feed it and what it'll hand back:

• Domain: -1 <= x <= 1
• Range: 0 <= y <= Pi

so like, you cannot just toss any random number in there, bestie. the domain is -1 <= x <= 1, periodt. stay in your lane and we stay slaying. 🌈

also important: this function operates on single-precision floating point values. if you're out here needing double-precision floats, go use SDL_acos instead — that's its whole thing. know the difference, it's giving iykyk. 👑

⚠️ lowkey important caveat: this function may use a different approximation across different versions, platforms and configurations. i.e, it can return a different value given the same input on different machines or operating systems, or if SDL is updated. so like… don't be out here expecting bit-for-bit identical results across the board. that's not the vibe it's promising. 😭

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🧚 FUNCTION PARAMETERS 🧚

• x — floating point value. that's the input, that's who we're acos-ing. 💜

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✨ RETURN VALUE ✨

returns the arc cosine of x, in radians. radians!! not degrees!! put the protractor down bestie, we're not doing that today. 🔥

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🫶 THREAD SAFETY 🫶

good news, main character: it is safe to call this function from any thread. go off, spawn as many threads as your heart desires, this one's not gonna betray you. 💖

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⭐ AVAILABILITY ⭐

this function is available since SDL 3.2.0. so if you're on something older than that… bestie, it's not there. upgrade time. 💀

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🌈 SEE ALSO 🌈

• SDL_acos(3) — the double-precision sibling, the more precise one, the older sister energy.
• SDL_asinf(3) — arc sine, the other trig bestie.
• SDL_cosf(3) — regular cosine, the one this is undoing. 🦋

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and that's the whole page, no notes. 💅 this lil manual page comes to you from Simple Directmedia Layer, and it's sitting pretty at version SDL 3.4.18. go forth and compute your arc cosines, babe — you've got this. 🎀✨🫶