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fixasin(3)			 Allegro manual 		      fixasin(3)

NAME
     fixasin  -  Fixed point inverse sine lookup table. Allegro game programming
     library.

SYNOPSIS
     #include <allegro.h>

     fixed fixasin(fixed x);

DESCRIPTION
     This function finds the inverse sine of a value using a lookup  table.  The
     input  value  must be a fixed point value. The inverse sine 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:

	float angle;
	fixed val;

	/* Sets `val' to a right binary angle (`64'). */
	val = fixasin(itofix(1));
	/* Sets `angle' to 0.2405. */
	angle = fixtof(fixmul(fixasin(ftofix(0.238)), fixtorad_r));
	/* This will trigger the assert. */
	val = fixasin(ftofix(-1.09));
	ASSERT(!errno);

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 the range. All  return
     values of this function will be in the range `-64' to `64'.

SEE ALSO
Allegro 			  version 4.4.3 		      fixasin(3)

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