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Remove residual floating point code from libgme's ym2612_emu. Saves several KB of codesize.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30496 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Andree Buschmann 2011-09-10 18:40:12 +00:00
parent 585eb12348
commit d4249affc4
2 changed files with 63 additions and 64 deletions
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1
apps/codecs/libgme/blargg_common.h
View file

@ -21,6 +21,7 @@
#endif
// common defines
#define FP_ONE_CLOCK (1LL << 12)
#define FP_ONE_TEMPO (1LL << 24)
#define FP_ONE_GAIN (1LL << 24)
#define FP_ONE_VOLUME FP_ONE_GAIN

126
apps/codecs/libgme/ym2612_emu.c
View file

@ -461,44 +461,23 @@ static int YM_SET( struct Ym2612_Impl* impl, int Adr, int data )
return 0;
}
#if defined(ROCKBOX)
double fabs(double x)
{
if (x < 0.0) return -x;
return x;
}
double ipow(double a,int b)
{
if (b < 0) {
a = 1.0 / a;
b = -b;
}
double result = 1.0;
while(b) {
if (b & 1) result*=a;
a *= a;
b >>= 1;
}
return result;
}
#endif
void impl_reset( struct Ym2612_Impl* impl );
static void impl_set_rate( struct Ym2612_Impl* impl, double sample_rate, double clock_rate )
static void impl_set_rate( struct Ym2612_Impl* impl, int sample_rate, int clock_rate )
{
assert( sample_rate );
assert( !clock_rate || clock_rate > sample_rate );
int i;
// 144 = 12 * (prescale * 2) = 12 * 6 * 2
// prescale set to 6 by default
double Frequence = (clock_rate ? clock_rate / sample_rate / 144.0 : 1.0);
if ( fabs( Frequence - 1.0 ) < 0.0000001 )
Frequence = 1.0;
impl->YM2612.TimerBase = (int) (Frequence * 4096.0);
int Frequency = (clock_rate ? (int)((FP_ONE_CLOCK * clock_rate) / sample_rate / 144) : (int)FP_ONE_CLOCK);
if ( abs( Frequency - FP_ONE_CLOCK ) < 1 )
Frequency = FP_ONE_CLOCK;
impl->YM2612.TimerBase = Frequency;
/* double Frequence = (double)Frequency / FP_ONE_CLOCK; */
// Tableau TL :
// [0 - 4095] = +output [4095 - ...] = +output overflow (fill with 0)
@ -571,11 +550,18 @@ static void impl_set_rate( struct Ym2612_Impl* impl, double sample_rate, double
{
// Attack curve (x^8 - music level 2 Vectorman 2)
#if defined(ROCKBOX)
double x = ipow( ((ENV_LENGHT - 1) - i) / (double) ENV_LENGHT, 8.0 );
int k;
int prescale = (31 - 2*ENV_HBITS); /* used to gain higher precision */
int x = ENV_LENGHT * (1 << prescale);
for ( k = 0; k < 8; ++k)
{
x = ( x * ((ENV_LENGHT - 1) - i) ) / ENV_LENGHT;
}
x >>= prescale;
#else
double x = pow( ((ENV_LENGHT - 1) - i) / (double) ENV_LENGHT, 8.0 );
x *= ENV_LENGHT;
#endif
x *= ENV_LENGHT;
impl->g.ENV_TAB [i] = (int) x;
@ -586,7 +572,7 @@ static void impl_set_rate( struct Ym2612_Impl* impl, double sample_rate, double
impl->g.ENV_TAB [i + ENV_LENGHT * 2] = 0;
impl->g.ENV_TAB [ENV_END >> ENV_LBITS] = ENV_LENGHT - 1; // for the stopped state
// Tableau pour la conversion Attack -> Decay and Decay -> Attack
int j = ENV_LENGHT - 1;
@ -599,28 +585,33 @@ static void impl_set_rate( struct Ym2612_Impl* impl, double sample_rate, double
}
// Tableau pour le Substain Level
for ( i = 0; i < 15; i++ )
{
double x = i * 3 / ENV_STEP; // 3 and not 6 (Mickey Mania first music for test)
int x = i * 3 * (int)( (1 << ENV_LBITS) / ENV_STEP); // 3 and not 6 (Mickey Mania first music for test)
impl->g.SL_TAB [i] = ((int) x << ENV_LBITS) + ENV_DECAY;
impl->g.SL_TAB [i] = x + ENV_DECAY;
}
impl->g.SL_TAB [15] = ((ENV_LENGHT - 1) << ENV_LBITS) + ENV_DECAY; // special case : volume off
// Tableau Frequency Step
{
// 0.5 because MUL = value * 2
// * 1 / 2 because MUL = value * 2
#if SIN_LBITS + SIN_HBITS - (21 - 7) < 0
double const factor = 0.5 / (1 << ((21 - 7) - SIN_LBITS - SIN_HBITS)) * Frequence;
/* double const factor = Frequence / 2.0 / (1 << ((21 - 7) - SIN_LBITS - SIN_HBITS)); */
int const factor = (int)(Frequency / 2 / (1 << ((21 - 7) - SIN_LBITS - SIN_HBITS)) / FP_ONE_CLOCK);
#else
double const factor = 0.5 * (1 << (SIN_LBITS + SIN_HBITS - (21 - 7))) * Frequence;
/* double const factor = Frequence / 2.0 * (1 << (SIN_LBITS + SIN_HBITS - (21 - 7))); */
int const factor = (int)(Frequency / 2 * (1 << (SIN_LBITS + SIN_HBITS - (21 - 7))) / FP_ONE_CLOCK);
#endif
for ( i = 0; i < 2048; i++ )
impl->g.FINC_TAB [i] = (unsigned) (i * factor);
{
impl->g.FINC_TAB [i] = i * factor;
}
}
// Tableaux Attack & Decay Rate
for ( i = 0; i < 4; i++ )
@ -628,19 +619,23 @@ static void impl_set_rate( struct Ym2612_Impl* impl, double sample_rate, double
impl->g.AR_TAB [i] = 0;
impl->g.DR_TAB [i] = 0;
}
for ( i = 0; i < 60; i++ )
{
double x =
(1.0 + ((i & 3) * 0.25)) * // bits 0-1 : x1.00, x1.25, x1.50, x1.75
{
long long x =
(4LL + ((i & 3))) * // bits 0-1 : 4*(x1.00, x1.25, x1.50, x1.75)
(ENV_LENGHT << ENV_LBITS) * // on ajuste pour le tableau impl->g.ENV_TAB
Frequence *
(1 << (i >> 2)); // bits 2-5 : shift bits (x2^0 - x2^15)
Frequency *
(1 << (i >> 2)) / // bits 2-5 : shift bits (x2^0 - x2^15)
FP_ONE_CLOCK / 4;
long long x_AR = x / AR_RATE;
long long x_DR = x / DR_RATE;
impl->g.AR_TAB [i + 4] = (unsigned int) (x / AR_RATE);
impl->g.DR_TAB [i + 4] = (unsigned int) (x / DR_RATE);
}
impl->g.AR_TAB [i + 4] = (unsigned int) ( x_AR > ((1LL<<32) - 1) ? ((1LL<<32) - 1) : x_AR );
impl->g.DR_TAB [i + 4] = (unsigned int) ( x_DR > ((1LL<<32) - 1) ? ((1LL<<32) - 1) : x_DR );
}
for ( i = 64; i < 96; i++ )
{
impl->g.AR_TAB [i] = impl->g.AR_TAB [63];
@ -651,36 +646,39 @@ static void impl_set_rate( struct Ym2612_Impl* impl, double sample_rate, double
for ( i = 96; i < 128; i++ )
impl->g.AR_TAB [i] = 0;
// Tableau Detune
{
#if SIN_LBITS + SIN_HBITS - 21 < 0
double const factor = 1.0 / (1 << (21 - SIN_LBITS - SIN_HBITS)) * Frequence;
/* double const factor = 1.0 / (1 << (21 - SIN_LBITS - SIN_HBITS)) * Frequence; */
int const factor = Frequency / (1 << (21 - SIN_LBITS - SIN_HBITS)) / FP_ONE_CLOCK;
#else
double const factor = (1 << (SIN_LBITS + SIN_HBITS - 21)) * Frequence;
/* double const factor = (1 << (SIN_LBITS + SIN_HBITS - 21)) * Frequence; */
int const factor = Frequency * (1 << (SIN_LBITS + SIN_HBITS - 21)) / FP_ONE_CLOCK;
#endif
for ( i = 0; i < 4; i++ )
{
int j;
for ( j = 0; j < 32; j++ )
{
double y = DT_DEF_TAB [(i << 5) + j] * factor;
/* double y = DT_DEF_TAB [(i << 5) + j] * factor; */
int y = DT_DEF_TAB [(i << 5) + j] * factor;
impl->g.DT_TAB [i + 0] [j] = (int) y;
impl->g.DT_TAB [i + 4] [j] = (int) -y;
}
}
}
// Tableau LFO
impl->g.LFO_INC_TAB [0] = (unsigned) (3.98 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [1] = (unsigned) (5.56 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [2] = (unsigned) (6.02 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [3] = (unsigned) (6.37 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [4] = (unsigned) (6.88 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [5] = (unsigned) (9.63 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [6] = (unsigned) (48.1 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [7] = (unsigned) (72.2 * (1 << (LFO_HBITS + LFO_LBITS)) / sample_rate);
impl->g.LFO_INC_TAB [0] = (int) (3.98 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [1] = (int) (5.56 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [2] = (int) (6.02 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [3] = (int) (6.37 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [4] = (int) (6.88 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [5] = (int) (9.63 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [6] = (int) (48.1 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl->g.LFO_INC_TAB [7] = (int) (72.2 * (1 << (LFO_HBITS + LFO_LBITS))) / sample_rate;
impl_reset( impl );
}
@ -693,7 +691,7 @@ const char* Ym2612_set_rate( struct Ym2612_Emu* this, int sample_rate, int clock
if (last_sample_rate == sample_rate && last_clock_rate == clock_rate) return 0;
#endif
memset( &this->impl.YM2612, 0, sizeof this->impl.YM2612 );
impl_set_rate( &this->impl, (double)sample_rate, (double)clock_rate );
impl_set_rate( &this->impl, sample_rate, clock_rate );
return 0;
}