refactoring. we only use the HermiteResampler

This commit is contained in:
Daryl Borth 2018-08-22 08:54:18 -06:00
parent cacc596722
commit f69cd5baee
2 changed files with 2 additions and 119 deletions

View File

@ -185,7 +185,6 @@
#include "../msu1.h" #include "../msu1.h"
#include "../snapshot.h" #include "../snapshot.h"
#include "../display.h" #include "../display.h"
#include "linear_resampler.h"
#include "hermite_resampler.h" #include "hermite_resampler.h"
#define APU_DEFAULT_INPUT_RATE 32040 #define APU_DEFAULT_INPUT_RATE 32040
@ -195,7 +194,6 @@
#define APU_DENOMINATOR_NTSC 328125 #define APU_DENOMINATOR_NTSC 328125
#define APU_NUMERATOR_PAL 34176 #define APU_NUMERATOR_PAL 34176
#define APU_DENOMINATOR_PAL 709379 #define APU_DENOMINATOR_PAL 709379
#define APU_DEFAULT_RESAMPLER HermiteResampler
SNES_SPC *spc_core = NULL; SNES_SPC *spc_core = NULL;
@ -557,7 +555,7 @@ bool8 S9xInitSound (int buffer_ms, int lag_ms)
arguments. Use 2x in the resampler for buffer leveling with SoundSync */ arguments. Use 2x in the resampler for buffer leveling with SoundSync */
if (!spc::resampler) if (!spc::resampler)
{ {
spc::resampler = new APU_DEFAULT_RESAMPLER(spc::buffer_size >> (Settings.SoundSync ? 0 : 1)); spc::resampler = new HermiteResampler(spc::buffer_size >> (Settings.SoundSync ? 0 : 1));
if (!spc::resampler) if (!spc::resampler)
{ {
delete[] spc::landing_buffer; delete[] spc::landing_buffer;
@ -570,7 +568,7 @@ bool8 S9xInitSound (int buffer_ms, int lag_ms)
if (!msu::resampler) if (!msu::resampler)
{ {
msu::resampler = new APU_DEFAULT_RESAMPLER(msu::buffer_size >> (Settings.SoundSync ? 0 : 1)); msu::resampler = new HermiteResampler(msu::buffer_size >> (Settings.SoundSync ? 0 : 1));
if (!msu::resampler) if (!msu::resampler)
{ {
delete[] msu::landing_buffer; delete[] msu::landing_buffer;

View File

@ -1,115 +0,0 @@
/* Simple fixed-point linear resampler by BearOso*/
#ifndef __LINEAR_RESAMPLER_H
#define __LINEAR_RESAMPLER_H
#include "resampler.h"
#include "../snes9x.h"
static const int f_prec = 15;
static const uint32 f__one = (1 << f_prec);
#define lerp(t, a, b) (((((b) - (a)) * (t)) >> f_prec) + (a))
class LinearResampler : public Resampler
{
protected:
uint32 f__r_step;
uint32 f__inv_r_step;
uint32 f__r_frac;
int r_left, r_right;
public:
LinearResampler (int num_samples) : Resampler (num_samples)
{
f__r_frac = 0;
}
~LinearResampler ()
{
}
void
time_ratio (double ratio)
{
if (ratio == 0.0)
ratio = 1.0;
f__r_step = (uint32) (ratio * f__one);
f__inv_r_step = (uint32) (f__one / ratio);
clear ();
}
void
clear (void)
{
ring_buffer::clear ();
f__r_frac = 0;
r_left = 0;
r_right = 0;
}
void
read (short *data, int num_samples)
{
int i_position = start >> 1;
short *internal_buffer = (short *) buffer;
int o_position = 0;
int consumed = 0;
int max_samples = (buffer_size >> 1);
while (o_position < num_samples && consumed < buffer_size)
{
if (f__r_step == f__one)
{
data[o_position] = internal_buffer[i_position];
data[o_position + 1] = internal_buffer[i_position + 1];
o_position += 2;
i_position += 2;
if (i_position >= max_samples)
i_position -= max_samples;
consumed += 2;
continue;
}
while (f__r_frac <= f__one && o_position < num_samples)
{
data[o_position] = lerp (f__r_frac,
r_left,
internal_buffer[i_position]);
data[o_position + 1] = lerp (f__r_frac,
r_right,
internal_buffer[i_position + 1]);
o_position += 2;
f__r_frac += f__r_step;
}
if (f__r_frac > f__one)
{
f__r_frac -= f__one;
r_left = internal_buffer[i_position];
r_right = internal_buffer[i_position + 1];
i_position += 2;
if (i_position >= max_samples)
i_position -= max_samples;
consumed += 2;
}
}
size -= consumed << 1;
start += consumed << 1;
if (start >= buffer_size)
start -= buffer_size;
}
inline int
avail (void)
{
return (((size >> 2) * f__inv_r_step) - ((f__r_frac * f__inv_r_step) >> f_prec)) >> (f_prec - 1);
}
};
#endif /* __LINEAR_RESAMPLER_H */