fixacos(3)                      Allegro manual                      fixacos(3)



NAME
       fixacos - Fixed point inverse cosine lookup table. Allegro game
       programming library.

SYNOPSIS
       #include <allegro.h>


       fixed fixacos(fixed x);

DESCRIPTION
       This function finds the inverse cosine of a value using a lookup table.
       The input value must be a fixed point radian. The inverse cosine is
       defined only in the domain from `-1' to `1'. Outside of this input
       range, the function will set `errno' to EDOM and return zero. Example:

          fixed result;

          /* Sets `result' to binary angle 128. */
          result = fixacos(itofix(-1));

RETURN VALUE
       Returns the inverse sine of a fixed point value, measured as fixed
       point binary format angle, or zero if the input was out of range. All
       return values of this function will be in the range `0' to `128'.


SEE ALSO
Allegro                          version 4.2.3                      fixacos(3)
