sintonia/library/ecasound-2.7.2/libecasound/audioio-loop.cpp

161 lines
3.8 KiB
C++

// ------------------------------------------------------------------------
// audioio-loop.cpp: Audio object that routes data between reads and writes
// Copyright (C) 2000-2001,2004,2007,2008 Kai Vehmanen
//
// Attributes:
// eca-style-version: 3
//
// 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 program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
// ------------------------------------------------------------------------
#include <cstdlib>
#include <string>
#include <kvu_dbc.h>
#include <kvu_numtostr.h>
#include "samplebuffer.h"
#include "sample-specs.h"
#include "audioio-buffered.h"
#include "audioio-loop.h"
#include "eca-error.h"
#include "eca-logger.h"
using std::string;
LOOP_DEVICE::LOOP_DEVICE(string tag)
: AUDIO_IO("loop", io_readwrite),
tag_rep(tag),
sbuf(buffersize(), 0)
{
writes_rep = 0;
registered_inputs_rep = 0;
registered_outputs_rep = 0;
filled_rep = false;
finished_rep = false;
empty_rounds_rep = 0;
}
LOOP_DEVICE::~LOOP_DEVICE(void)
{
if (is_open() == true) {
close();
}
}
LOOP_DEVICE* LOOP_DEVICE::clone(void) const
{
LOOP_DEVICE* target = new LOOP_DEVICE();
for(int n = 0; n < number_of_params(); n++) {
target->set_parameter(n + 1, get_parameter(n + 1));
}
return target;
}
bool LOOP_DEVICE::finished(void) const
{
return finished_rep;
}
SAMPLE_SPECS::sample_pos_t LOOP_DEVICE::seek_position(SAMPLE_SPECS::sample_pos_t pos)
{
writes_rep = 0;
empty_rounds_rep = 0;
filled_rep = false;
finished_rep = false;
return pos;
}
void LOOP_DEVICE::read_buffer(SAMPLE_BUFFER* buffer)
{
if (empty_rounds_rep == 0) {
if (filled_rep == true) {
buffer->copy_all_content(sbuf);
/* note: read_buffer() should never be called in the middle
* of the 'X * write_buffer()' sequence (where X is the number
* of chain outputs connected to this loop device */
DBC_CHECK(writes_rep == 0);
}
else {
buffer->number_of_channels(channels());
buffer->make_silent();
}
}
else {
finished_rep = true;
buffer->number_of_channels(channels());
buffer->make_silent();
}
DBC_ENSURE(buffer->number_of_channels() == channels());
}
void LOOP_DEVICE::write_buffer(SAMPLE_BUFFER* buffer)
{
++writes_rep;
/* first write of a new engine iteration (and after a read) */
if (writes_rep == 1) {
change_position_in_samples(buffer->length_in_samples());
extend_position();
sbuf.number_of_channels(channels());
sbuf.make_silent();
}
/* check if this is the last write for this engine iteration */
if (writes_rep == registered_outputs_rep)
writes_rep = 0;
/* store data from 'buffer' */
if (buffer->is_empty() != true) {
empty_rounds_rep = 0;
sbuf.add_with_weight(*buffer, registered_outputs_rep);
filled_rep = true;
}
/* empty 'buffer' */
else {
++empty_rounds_rep;
}
DBC_CHECK(sbuf.number_of_channels() == channels());
}
void LOOP_DEVICE::set_parameter(int param,
string value)
{
switch (param) {
case 1:
AUDIO_IO::set_parameter(param, value);
break;
case 2:
tag_rep = value;
break;
}
}
string LOOP_DEVICE::get_parameter(int param) const
{
switch (param) {
case 1:
return AUDIO_IO::get_parameter(param);
case 2:
return tag_rep;
}
return "";
}