mirror of
https://github.com/ZDoom/qzdoom.git
synced 2024-11-14 16:41:07 +00:00
137 lines
3.6 KiB
C++
137 lines
3.6 KiB
C++
// Game_Music_Emu 0.6.0. http://www.slack.net/~ant/
|
|
|
|
#include "Dual_Resampler.h"
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
/* Copyright (C) 2003-2006 Shay Green. This module is free software; you
|
|
can redistribute it and/or modify it under the terms of the GNU Lesser
|
|
General Public License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version. This
|
|
module is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
|
|
details. You should have received a copy of the GNU Lesser General Public
|
|
License along with this module; if not, write to the Free Software Foundation,
|
|
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
|
|
|
|
#include "blargg_source.h"
|
|
|
|
unsigned const resampler_extra = 256;
|
|
|
|
Dual_Resampler::Dual_Resampler() :
|
|
sample_buf_size(0),
|
|
oversamples_per_frame(-1),
|
|
buf_pos(-1),
|
|
resampler_size(0)
|
|
{
|
|
}
|
|
|
|
Dual_Resampler::~Dual_Resampler() { }
|
|
|
|
blargg_err_t Dual_Resampler::reset( int pairs )
|
|
{
|
|
// expand allocations a bit
|
|
RETURN_ERR( sample_buf.resize( (pairs + (pairs >> 2)) * 2 ) );
|
|
resize( pairs );
|
|
resampler_size = oversamples_per_frame + (oversamples_per_frame >> 2);
|
|
return resampler.buffer_size( resampler_size );
|
|
}
|
|
|
|
void Dual_Resampler::resize( int pairs )
|
|
{
|
|
int new_sample_buf_size = pairs * 2;
|
|
if ( sample_buf_size != new_sample_buf_size )
|
|
{
|
|
if ( (unsigned) new_sample_buf_size > sample_buf.size() )
|
|
{
|
|
check( false );
|
|
return;
|
|
}
|
|
sample_buf_size = new_sample_buf_size;
|
|
oversamples_per_frame = int (pairs * resampler.ratio()) * 2 + 2;
|
|
clear();
|
|
}
|
|
}
|
|
|
|
void Dual_Resampler::play_frame_( Blip_Buffer& blip_buf, dsample_t* out )
|
|
{
|
|
long pair_count = sample_buf_size >> 1;
|
|
blip_time_t blip_time = blip_buf.count_clocks( pair_count );
|
|
int sample_count = oversamples_per_frame - resampler.written();
|
|
|
|
int new_count = play_frame( blip_time, sample_count, resampler.buffer() );
|
|
assert( new_count < resampler_size );
|
|
|
|
blip_buf.end_frame( blip_time );
|
|
assert( blip_buf.samples_avail() == pair_count );
|
|
|
|
resampler.write( new_count );
|
|
|
|
long count = resampler.read( sample_buf.begin(), sample_buf_size );
|
|
assert( count == (long) sample_buf_size );
|
|
|
|
mix_samples( blip_buf, out );
|
|
blip_buf.remove_samples( pair_count );
|
|
}
|
|
|
|
void Dual_Resampler::dual_play( long count, dsample_t* out, Blip_Buffer& blip_buf )
|
|
{
|
|
// empty extra buffer
|
|
long remain = sample_buf_size - buf_pos;
|
|
if ( remain )
|
|
{
|
|
if ( remain > count )
|
|
remain = count;
|
|
count -= remain;
|
|
memcpy( out, &sample_buf [buf_pos], remain * sizeof *out );
|
|
out += remain;
|
|
buf_pos += remain;
|
|
}
|
|
|
|
// entire frames
|
|
while ( count >= (long) sample_buf_size )
|
|
{
|
|
play_frame_( blip_buf, out );
|
|
out += sample_buf_size;
|
|
count -= sample_buf_size;
|
|
}
|
|
|
|
// extra
|
|
if ( count )
|
|
{
|
|
play_frame_( blip_buf, sample_buf.begin() );
|
|
buf_pos = count;
|
|
memcpy( out, sample_buf.begin(), count * sizeof *out );
|
|
out += count;
|
|
}
|
|
}
|
|
|
|
void Dual_Resampler::mix_samples( Blip_Buffer& blip_buf, dsample_t* out )
|
|
{
|
|
Blip_Reader sn;
|
|
int bass = sn.begin( blip_buf );
|
|
const dsample_t* in = sample_buf.begin();
|
|
|
|
for ( int n = sample_buf_size >> 1; n--; )
|
|
{
|
|
int s = sn.read();
|
|
blargg_long l = (blargg_long) in [0] * 2 + s;
|
|
if ( (BOOST::int16_t) l != l )
|
|
l = 0x7FFF - (l >> 24);
|
|
|
|
sn.next( bass );
|
|
blargg_long r = (blargg_long) in [1] * 2 + s;
|
|
if ( (BOOST::int16_t) r != r )
|
|
r = 0x7FFF - (r >> 24);
|
|
|
|
in += 2;
|
|
out [0] = (dsample_t)l;
|
|
out [1] = (dsample_t)r;
|
|
out += 2;
|
|
}
|
|
|
|
sn.end( blip_buf );
|
|
}
|
|
|