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al_fixatan2(3)							al_fixatan2(3)

NAME
       al_fixatan2 - Allegro 5 API

SYNOPSIS
	      #include <allegro5/allegro.h>

	      al_fixed al_fixatan2(al_fixed y, al_fixed	x)

DESCRIPTION
       This is a fixed point version of	the libc atan2() routine.  It computes
       the arc tangent of y / x, but the signs of both arguments are  used  to
       determine  the  quadrant	 of the	result,	and x is permitted to be zero.
       This function is	useful to convert Cartesian coordinates	to polar coor-
       dinates.

       Example:

		  al_fixed result;

		  /* Sets `result' to binary angle 64. */
		  result = al_fixatan2(al_itofix(1), 0);

		  /* Sets `result' to binary angle -109. */
		  result = al_fixatan2(al_itofix(-1), al_itofix(-2));

		  /* Fails the assert. */
		  result = al_fixatan2(0, 0);
		  assert(!al_get_errno());

RETURN VALUE
       Returns	the  arc  tangent of y / x in fixed point binary format	angle,
       from -128 to 128.  If both x and	y are zero, returns zero and sets  Al-
       legro's errno to	EDOM.

Allegro	reference manual					al_fixatan2(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE

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