fixatan2(3) - Linux man page
Name
fixatan2 - Fixed point version of the libc atan2() routine. Allegro game programming library.Synopsis
#include <allegro.h>fixed fixatan2(fixed y, fixed x);
Description
This is a fixed point version of the libc atan2() routine. It computes the arc tangent of 'y / x', but the signs of both arguments are used to determine the quadrant of the result, and 'x' is permitted to be zero. This function is useful to convert Cartesian coordinates to polar coordinates. Example:fixed result; /* Sets 'result' to binary angle 64. */ result = fixatan2(itofix(1), 0); /* Sets 'result' to binary angle -109. */ result = fixatan2(itofix(-1), itofix(-2)); /* Fails the assert. */ result = fixatan2(0, 0); ASSERT(!errno);