al_fixtan - Allegro 5 API

       This  function  finds the tangent of a value using a lookup table.  The input value must be a fixed point
       binary angle.

       Example:

              al_fixed angle, res_a, res_b;
              float dif;

              angle = al_itofix(37);
              /* Prove that tan(angle) == sin(angle) / cos(angle). */
              res_a = al_fixdiv(al_fixsin(angle), al_fixcos(angle));
              res_b = al_fixtan(angle);
              dif = al_fixtof(al_fixsub(res_a, res_b));
              printf("Precision error: %f\n", dif);

       al_fixtan - Allegro 5 API

       Returns the tangent of a fixed point binary format angle as a fixed point value.

Allegro reference manual                                                                      al_fixtan(3alleg5)

              #include <allegro5/allegro.h>

              al_fixed al_fixtan(al_fixed x);