NAME

       al_fixacos - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro.h>

              al_fixed al_fixacos(al_fixed x);

DESCRIPTION

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

       Example:

              al_fixed result;

              /* Sets result to binary angle 128. */
              result = al_fixacos(al_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.