Revert "Consolidate all fixed point math routines in one library (FS#10400) by Jeffrey Goode"

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21635 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 0 insertions, 440 deletions

diff --git a/apps/fixedpoint.c b/apps/fixedpoint.c
deleted file mode 100644
index 7738dc123e..0000000000
--- a/apps/fixedpoint.c
+++ /dev/null
@@ -1,440 +0,0 @@
-/***************************************************************************
- *             __________               __   ___.
- *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
- *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
- *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
- *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
- *                     \/            \/     \/    \/            \/
- * $Id$
- *
- * Copyright (C) 2006 Jens Arnold
- *
- * Fixed point library for plugins
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
- * KIND, either express or implied.
- *
- ****************************************************************************/
-
-#include "fixedpoint.h"
-#include <stdlib.h>
-#include <stdbool.h>
-
-#ifndef BIT_N
-#define BIT_N(n) (1U << (n))
-#endif
-
-/** TAKEN FROM ORIGINAL fixedpoint.h */
-/* Inverse gain of circular cordic rotation in s0.31 format. */
-static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */
-
-/* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */
-static const unsigned long atan_table[] = {
-    0x1fffffff, /* +0.785398163 (or pi/4) */
-    0x12e4051d, /* +0.463647609 */
-    0x09fb385b, /* +0.244978663 */
-    0x051111d4, /* +0.124354995 */
-    0x028b0d43, /* +0.062418810 */
-    0x0145d7e1, /* +0.031239833 */
-    0x00a2f61e, /* +0.015623729 */
-    0x00517c55, /* +0.007812341 */
-    0x0028be53, /* +0.003906230 */
-    0x00145f2e, /* +0.001953123 */
-    0x000a2f98, /* +0.000976562 */
-    0x000517cc, /* +0.000488281 */
-    0x00028be6, /* +0.000244141 */
-    0x000145f3, /* +0.000122070 */
-    0x0000a2f9, /* +0.000061035 */
-    0x0000517c, /* +0.000030518 */
-    0x000028be, /* +0.000015259 */
-    0x0000145f, /* +0.000007629 */
-    0x00000a2f, /* +0.000003815 */
-    0x00000517, /* +0.000001907 */
-    0x0000028b, /* +0.000000954 */
-    0x00000145, /* +0.000000477 */
-    0x000000a2, /* +0.000000238 */
-    0x00000051, /* +0.000000119 */
-    0x00000028, /* +0.000000060 */
-    0x00000014, /* +0.000000030 */
-    0x0000000a, /* +0.000000015 */
-    0x00000005, /* +0.000000007 */
-    0x00000002, /* +0.000000004 */
-    0x00000001, /* +0.000000002 */
-    0x00000000, /* +0.000000001 */
-    0x00000000, /* +0.000000000 */
-};
-
-/* Precalculated sine and cosine * 16384 (2^14) (fixed point 18.14) */
-static const short sin_table[91] =
-{
-        0,   285,   571,   857,  1142,  1427,  1712,  1996,  2280,  2563,
-     2845,  3126,  3406,  3685,  3963,  4240,  4516,  4790,  5062,  5334,
-     5603,  5871,  6137,  6401,  6663,  6924,  7182,  7438,  7691,  7943,
-     8191,  8438,  8682,  8923,  9161,  9397,  9630,  9860, 10086, 10310,
-    10531, 10748, 10963, 11173, 11381, 11585, 11785, 11982, 12175, 12365,
-    12550, 12732, 12910, 13084, 13254, 13420, 13582, 13740, 13894, 14043,
-    14188, 14329, 14466, 14598, 14725, 14848, 14967, 15081, 15190, 15295,
-    15395, 15491, 15582, 15668, 15749, 15825, 15897, 15964, 16025, 16082,
-    16135, 16182, 16224, 16261, 16294, 16321, 16344, 16361, 16374, 16381,
-    16384
-};
-
-/**
- * Implements sin and cos using CORDIC rotation.
- *
- * @param phase has range from 0 to 0xffffffff, representing 0 and
- *        2*pi respectively.
- * @param cos return address for cos
- * @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX,
- *         representing -1 and 1 respectively. 
- */
-long fsincos(unsigned long phase, long *cos) 
-{
-    int32_t x, x1, y, y1;
-    unsigned long z, z1;
-    int i;
-
-    /* Setup initial vector */
-    x = cordic_circular_gain;
-    y = 0;
-    z = phase;
-
-    /* The phase has to be somewhere between 0..pi for this to work right */
-    if (z < 0xffffffff / 4) {
-        /* z in first quadrant, z += pi/2 to correct */
-        x = -x;
-        z += 0xffffffff / 4;
-    } else if (z < 3 * (0xffffffff / 4)) {
-        /* z in third quadrant, z -= pi/2 to correct */
-        z -= 0xffffffff / 4;
-    } else {
-        /* z in fourth quadrant, z -= 3pi/2 to correct */
-        x = -x;
-        z -= 3 * (0xffffffff / 4);
-    }
-
-    /* Each iteration adds roughly 1-bit of extra precision */
-    for (i = 0; i < 31; i++) {
-        x1 = x >> i;
-        y1 = y >> i;
-        z1 = atan_table[i];
-
-        /* Decided which direction to rotate vector. Pivot point is pi/2 */
-        if (z >= 0xffffffff / 4) {
-            x -= y1;
-            y += x1;
-            z -= z1;
-        } else {
-            x += y1;
-            y -= x1;
-            z += z1;
-        }
-    }
-
-    if (cos)
-        *cos = x;
-
-    return y;
-}
-
-/**
- * Fixed point square root via Newton-Raphson.
- * @param x square root argument.
- * @param fracbits specifies number of fractional bits in argument.
- * @return Square root of argument in same fixed point format as input.
- *
- * This routine has been modified to run longer for greater precision,
- * but cuts calculation short if the answer is reached sooner.  In
- * general, the closer x is to 1, the quicker the calculation. 
- */
-long fsqrt(long x, unsigned int fracbits)
-{
-    long b = x/2 + BIT_N(fracbits); /* initial approximation */
-    long c;
-    unsigned n;
-    const unsigned iterations = 8;
-    
-    for (n = 0; n < iterations; ++n)
-    {
-        c = DIV64(x, b, fracbits);
-        if (c == b) break;
-        b = (b + c)/2;
-    }
-
-    return b;
-}
-
-/**
- * Fixed point sinus using a lookup table
- * don't forget to divide the result by 16384 to get the actual sinus value
- * @param val sinus argument in degree
- * @return sin(val)*16384
- */
-long sin_int(int val)
-{
-    val = (val+360)%360;
-    if (val < 181)
-    {
-        if (val < 91)/* phase 0-90 degree */
-            return (long)sin_table[val];
-        else/* phase 91-180 degree */
-            return (long)sin_table[180-val];
-    }
-    else
-    {
-        if (val < 271)/* phase 181-270 degree */
-            return -(long)sin_table[val-180];
-        else/* phase 270-359 degree */
-            return -(long)sin_table[360-val];
-    }
-    return 0;
-}
-
-/**
- * Fixed point cosinus using a lookup table
- * don't forget to divide the result by 16384 to get the actual cosinus value
- * @param val sinus argument in degree
- * @return cos(val)*16384
- */
-long cos_int(int val)
-{
-    val = (val+360)%360;
-    if (val < 181)
-    {
-        if (val < 91)/* phase 0-90 degree */
-            return (long)sin_table[90-val];
-        else/* phase 91-180 degree */
-            return -(long)sin_table[val-90];
-    }
-    else
-    {
-        if (val < 271)/* phase 181-270 degree */
-            return -(long)sin_table[270-val];
-        else/* phase 270-359 degree */
-            return (long)sin_table[val-270];
-    }
-    return 0;
-}
-
-/**
- * Fixed-point natural log
- * taken from http://www.quinapalus.com/efunc.html
- *  "The code assumes integers are at least 32 bits long. The (positive)
- *   argument and the result of the function are both expressed as fixed-point
- *   values with 16 fractional bits, although intermediates are kept with 28
- *   bits of precision to avoid loss of accuracy during shifts."
- */
-
-long flog(int x) {
-    long t,y;
-
-    y=0xa65af;
-    if(x<0x00008000) x<<=16,              y-=0xb1721;
-    if(x<0x00800000) x<<= 8,              y-=0x58b91;
-    if(x<0x08000000) x<<= 4,              y-=0x2c5c8;
-    if(x<0x20000000) x<<= 2,              y-=0x162e4;
-    if(x<0x40000000) x<<= 1,              y-=0x0b172;
-    t=x+(x>>1); if((t&0x80000000)==0) x=t,y-=0x067cd;
-    t=x+(x>>2); if((t&0x80000000)==0) x=t,y-=0x03920;
-    t=x+(x>>3); if((t&0x80000000)==0) x=t,y-=0x01e27;
-    t=x+(x>>4); if((t&0x80000000)==0) x=t,y-=0x00f85;
-    t=x+(x>>5); if((t&0x80000000)==0) x=t,y-=0x007e1;
-    t=x+(x>>6); if((t&0x80000000)==0) x=t,y-=0x003f8;
-    t=x+(x>>7); if((t&0x80000000)==0) x=t,y-=0x001fe;
-    x=0x80000000-x;
-    y-=x>>15;
-    return y;
-}
-
-/** MODIFIED FROM replaygain.c */
-/* These math routines have 64-bit internal precision to avoid overflows.
- * Arguments and return values are 32-bit (long) precision.
- */
- 
-#define FP_MUL64(x, y) (((x) * (y)) >> (fracbits))
-#define FP_DIV64(x, y) (((x) << (fracbits)) / (y))
-
-static long long fp_exp10(long long x, unsigned int fracbits);
-static long long fp_log10(long long n, unsigned int fracbits);
-
-/* constants in fixed point format, 28 fractional bits */
-#define FP28_LN2        (186065279LL)   /* ln(2)        */
-#define FP28_LN2_INV    (387270501LL)   /* 1/ln(2)      */
-#define FP28_EXP_ZERO   (44739243LL)    /* 1/6          */
-#define FP28_EXP_ONE    (-745654LL)     /* -1/360       */
-#define FP28_EXP_TWO    (12428LL)       /* 1/21600      */
-#define FP28_LN10       (618095479LL)   /* ln(10)       */
-#define FP28_LOG10OF2   (80807124LL)    /* log10(2)     */
-
-#define TOL_BITS         2              /* log calculation tolerance */
-
-
-/* The fpexp10 fixed point math routine is based
- * on oMathFP by Dan Carter (http://orbisstudios.com).
- */
-
-/** FIXED POINT EXP10
- * Return 10^x as FP integer.  Argument is FP integer.
- */
-static long long fp_exp10(long long x, unsigned int fracbits)
-{
-    long long k;
-    long long z;
-    long long R;
-    long long xp;
-    
-    /* scale constants */
-    const long long fp_one      = (1 << fracbits);
-    const long long fp_half     = (1 << (fracbits - 1));
-    const long long fp_two      = (2 << fracbits);
-    const long long fp_mask     = (fp_one - 1);
-    const long long fp_ln2_inv  = (FP28_LN2_INV     >> (28 - fracbits));
-    const long long fp_ln2      = (FP28_LN2         >> (28 - fracbits));
-    const long long fp_ln10     = (FP28_LN10        >> (28 - fracbits));
-    const long long fp_exp_zero = (FP28_EXP_ZERO    >> (28 - fracbits));
-    const long long fp_exp_one  = (FP28_EXP_ONE     >> (28 - fracbits));
-    const long long fp_exp_two  = (FP28_EXP_TWO     >> (28 - fracbits));
-    
-    /* exp(0) = 1 */
-    if (x == 0)
-    {
-        return fp_one;
-    }
-    
-    /* convert from base 10 to base e */
-    x = FP_MUL64(x, fp_ln10);
-    
-    /* calculate exp(x) */
-    k = (FP_MUL64(abs(x), fp_ln2_inv) + fp_half) & ~fp_mask;
-    
-    if (x < 0)
-    {
-        k = -k;
-    }
-    
-    x -= FP_MUL64(k, fp_ln2);
-    z = FP_MUL64(x, x);
-    R = fp_two + FP_MUL64(z, fp_exp_zero + FP_MUL64(z, fp_exp_one
-        + FP_MUL64(z, fp_exp_two)));
-    xp = fp_one + FP_DIV64(FP_MUL64(fp_two, x), R - x);
-    
-    if (k < 0)
-    {
-        k = fp_one >> (-k >> fracbits);
-    }
-    else
-    {
-        k = fp_one << (k >> fracbits);
-    }
-    
-    return FP_MUL64(k, xp);
-}
-
-
-/** FIXED POINT LOG10
- * Return log10(x) as FP integer.  Argument is FP integer.
- */
-static long long fp_log10(long long n, unsigned int fracbits)
-{
-    /* Calculate log2 of argument */
-
-    long long log2, frac;
-    const long long fp_one  = (1 << fracbits);
-    const long long fp_two  = (2 << fracbits);
-    const long tolerance    = (1 << ((fracbits / 2) + 2));
-    
-    if (n <=0) return FP_NEGINF;
-    log2 = 0;
-
-    /* integer part */
-    while (n < fp_one)
-    {
-        log2 -= fp_one;
-        n <<= 1;
-    }
-    while (n >= fp_two)
-    {
-        log2 += fp_one;
-        n >>= 1;
-    }
-    
-    /* fractional part */
-    frac = fp_one;
-    while (frac > tolerance)
-    {
-        frac >>= 1;
-        n = FP_MUL64(n, n);
-        if (n >= fp_two)
-        {
-            n >>= 1;
-            log2 += frac;
-        }
-    }
-    
-    /* convert log2 to log10 */
-    return FP_MUL64(log2, (FP28_LOG10OF2 >> (28 - fracbits)));
-}
-
-
-/** CONVERT FACTOR TO DECIBELS */
-long fp_decibels(unsigned long factor, unsigned int fracbits)
-{
-    long long decibels;
-    long long f = (long long)factor;
-    bool neg;
-    
-    /* keep factor in signed long range */
-    if (f >= (1LL << 31))
-        f = (1LL << 31) - 1;
-    
-    /* decibels = 20 * log10(factor) */
-    decibels = FP_MUL64((20LL << fracbits), fp_log10(f, fracbits));
-    
-    /* keep result in signed long range */
-    if ((neg = (decibels < 0)))
-        decibels = -decibels;
-    if (decibels >= (1LL << 31))
-        return neg ? FP_NEGINF : FP_INF;
-    
-    return neg ? (long)-decibels : (long)decibels;
-}
-
-
-/** CONVERT DECIBELS TO FACTOR */
-long fp_factor(long decibels, unsigned int fracbits)
-{
-    bool neg;
-    long long factor;
-    long long db = (long long)decibels;
-    
-    /* if decibels is 0, factor is 1 */
-    if (db == 0)
-        return (1L << fracbits);
-    
-    /* calculate for positive decibels only */
-    if ((neg = (db < 0)))
-        db = -db;
-    
-    /* factor = 10 ^ (decibels / 20) */
-    factor = fp_exp10(FP_DIV64(db, (20LL << fracbits)), fracbits);
-    
-    /* keep result in signed long range, return 0 if very small */
-    if (factor >= (1LL << 31))
-    {
-        if (neg)
-            return 0;
-        else
-            return FP_INF;
-    }
-    
-    /* if negative argument, factor is 1 / result */
-    if (neg)
-        factor = FP_DIV64((1LL << fracbits), factor);
-        
-    return (long)factor;
-}