fixacos

fixacos(3alleg4)                 Allegro manual                 fixacos(3alleg4)



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 4.4.3                 fixacos(3alleg4)