blender/intern/audaspace/FX/AUD_FaderReader.cpp
Joerg Mueller cc71dcc218 3D Audio GSoC:
Streaming improved.
2011-06-21 20:14:53 +00:00

89 lines
2.1 KiB
C++

/*
* $Id$
*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* Copyright 2009-2011 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 General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Audaspace; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* ***** END GPL LICENSE BLOCK *****
*/
/** \file audaspace/FX/AUD_FaderReader.cpp
* \ingroup audfx
*/
#include "AUD_FaderReader.h"
#include <cstring>
AUD_FaderReader::AUD_FaderReader(AUD_Reference<AUD_IReader> reader, AUD_FadeType type,
float start,float length) :
AUD_EffectReader(reader),
m_type(type),
m_start(start),
m_length(length)
{
}
void AUD_FaderReader::read(int& length, bool& eos, sample_t* buffer)
{
int position = m_reader->getPosition();
AUD_Specs specs = m_reader->getSpecs();
int samplesize = AUD_SAMPLE_SIZE(specs);
m_reader->read(length, eos, buffer);
if((position + length) / (float)specs.rate <= m_start)
{
if(m_type != AUD_FADE_OUT)
{
memset(buffer, 0, length * samplesize);
}
}
else if(position / (float)specs.rate >= m_start+m_length)
{
if(m_type == AUD_FADE_OUT)
{
memset(buffer, 0, length * samplesize);
}
}
else
{
float volume = 1.0f;
for(int i = 0; i < length * specs.channels; i++)
{
if(i % specs.channels == 0)
{
volume = (((position+i)/(float)specs.rate)-m_start) / m_length;
if(volume > 1.0f)
volume = 1.0f;
else if(volume < 0.0f)
volume = 0.0f;
if(m_type == AUD_FADE_OUT)
volume = 1.0f - volume;
}
buffer[i] = buffer[i] * volume;
}
}
}