shithub: rgbds

ref: c0a9cf79a32d93079b471ad61b767b538d1213c1
dir: /src/asm/math.c/

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/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * INCLUDES
 *
 */

#include	<math.h>
#include	<stdio.h>
#include	"types.h"
#include	"mymath.h"
#include	"symbol.h"

#define	fix2double(i)	((double)(i/65536.0))
#define	double2fix(d)	((SLONG)(d*65536.0))
#ifndef	PI
#define	PI					(acos(-1))
#endif

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Define the _PI symbol
 *
 */

void    math_DefinePI (void)
{
    sym_AddEqu ("_PI", double2fix (PI));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Print a fixed point value
 *
 */

void    math_Print (SLONG i)
{
    if (i >= 0)
		printf ("%ld.%05ld", i >> 16, ((SLONG) (fix2double (i) * 100000 + 0.5)) % 100000);
    else
		printf ("-%ld.%05ld", (-i) >> 16, ((SLONG) (fix2double (-i) * 100000 + 0.5)) % 100000);
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate sine
 *
 */

SLONG   math_Sin (SLONG i)
{
    return (double2fix (sin (fix2double (i) * 2 * PI / 65536)));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate cosine
 *
 */

SLONG   math_Cos (SLONG i)
{
    return (double2fix (cos (fix2double (i) * 2 * PI / 65536)));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate tangent
 *
 */

SLONG   math_Tan (SLONG i)
{
    return (double2fix (tan (fix2double (i) * 2 * PI / 65536)));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate sine^-1
 *
 */

SLONG   math_ASin (SLONG i)
{
    return (double2fix (asin (fix2double (i)) / 2 / PI * 65536));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate cosine^-1
 *
 */

SLONG   math_ACos (SLONG i)
{
    return (double2fix (acos (fix2double (i)) / 2 / PI * 65536));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate tangent^-1
 *
 */

SLONG   math_ATan (SLONG i)
{
    return (double2fix (atan (fix2double (i)) / 2 / PI * 65536));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Calculate atan2
 *
 */

SLONG   math_ATan2 (SLONG i, SLONG j)
{
    return (double2fix (atan2 (fix2double (i), fix2double (j)) / 2 / PI * 65536));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Multiplication
 *
 */

SLONG   math_Mul (SLONG i, SLONG j)
{
    return (double2fix (fix2double (i) * fix2double (j)));
}

/*
 * RGBAsm - MATH.C (Fixedpoint math routines)
 *
 * Division
 *
 */

SLONG   math_Div (SLONG i, SLONG j)
{
    return (double2fix (fix2double (i) / fix2double (j)));
}