(This is the documentation for SDL3, which is under heavy development and the API is changing! SDL2 is the current stable version!)

SDL_atan

Compute the arc tangent of x.

Header File

Syntax

double SDL_atan(double x);

Function Parameters

x	floating point value.

Return Value

Returns arc tangent of of x in radians, or 0 if x = 0.

Remarks

The definition of y = atan(x) is x = tan(y).

Domain: -INF <= x <= INF

Range: -Pi/2 <= y <= Pi/2

This function operates on double-precision floating point values, use SDL_atanf for single-precision floats.

To calculate the arc tangent of y / x, use SDL_atan2.

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.

Version

This function is available since SDL 3.0.0.