blender/intern/audaspace/FX/AUD_ReverseReader.cpp
Joerg Mueller ce44d63ae1 Audaspace:
* Added an error string for audaspace exceptions.
* Fixed PyAPI exceptions.
* Minor bugfixes.
* Added a name parameter to the Jack device, so that one can define an own name via Python.
2010-08-03 08:07:21 +00:00

102 lines
2.3 KiB
C++

/*
* $Id$
*
* ***** BEGIN LGPL LICENSE BLOCK *****
*
* Copyright 2009 Jörg Hermann Müller
*
* This file is part of AudaSpace.
*
* AudaSpace 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 3 of the License, or
* (at your option) any later version.
*
* AudaSpace 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 AudaSpace. If not, see <http://www.gnu.org/licenses/>.
*
* ***** END LGPL LICENSE BLOCK *****
*/
#include "AUD_ReverseReader.h"
#include <cstring>
static const char* props_error = "AUD_ReverseReader: The reader has to be "
"seekable and a finite length.";
AUD_ReverseReader::AUD_ReverseReader(AUD_IReader* reader) :
AUD_EffectReader(reader),
m_length(reader->getLength()),
m_position(0)
{
if(m_length < 0 || !reader->isSeekable())
AUD_THROW(AUD_ERROR_PROPS, props_error);
}
void AUD_ReverseReader::seek(int position)
{
m_position = position;
}
int AUD_ReverseReader::getLength() const
{
return m_length;
}
int AUD_ReverseReader::getPosition() const
{
return m_position;
}
void AUD_ReverseReader::read(int & length, sample_t* & buffer)
{
// first correct the length
if(m_position + length > m_length)
length = m_length - m_position;
if(length <= 0)
{
length = 0;
return;
}
AUD_Specs specs = getSpecs();
int samplesize = AUD_SAMPLE_SIZE(specs);
// resize buffer if needed
if(m_buffer.getSize() < length * samplesize)
m_buffer.resize(length * samplesize);
buffer = m_buffer.getBuffer();
sample_t* buf;
int len = length;
// read from reader
m_reader->seek(m_length - m_position - len);
m_reader->read(len, buf);
// set null if reader didn't give enough data
if(len < length)
{
memset(buffer, 0, (length - len) * samplesize);
buffer += (length - len) * specs.channels;
}
// copy the samples reverted
for(int i = 0; i < len; i++)
memcpy(buffer + i * specs.channels,
buf + (len - 1 - i) * specs.channels,
samplesize);
m_position += length;
buffer = m_buffer.getBuffer();
}