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fixtan(3alleg4) Allegro manual fixtan(3alleg4)

fixtan - Fixed point tangent of binary angles. Allegro game programming library.

#include <allegro.h>

fixed fixtan(fixed x);

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


fixed angle, res_a, res_b;
float dif;

angle = itofix(37);
/* Prove that tan(angle) == sin(angle) / cos(angle). */
res_a = fixdiv(fixsin(angle), fixcos(angle));
res_b = fixtan(angle);
dif = fixtof(fixsub(res_a, res_b));
allegro_message("Precision error: %f\n", dif);

Returns the tangent of a fixed point binary format angle. The return value will be in radians.

version 4.4.3 Allegro