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/**
* @file windows_volume_catcher.cpp
* @brief A Windows implementation of volume level control of all audio channels opened by a process.
*
* @cond
* $LicenseInfo:firstyear=2010&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2010, Linden Research, Inc.
*
* This library 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;
* version 2.1 of the License only.
*
* This library 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 library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
* @endcond
*/
#include "volume_catcher.h"
#include "llsingleton.h"
#include <windows.h>
#include <mmeapi.h>
class VolumeCatcherImpl : public LLSingleton<VolumeCatcherImpl>
{
LLSINGLETON(VolumeCatcherImpl);
// This is a singleton class -- both callers and the component implementation should use getInstance() to find the instance.
~VolumeCatcherImpl();
public:
void setVolume(F32 volume);
void setPan(F32 pan);
private:
F32 mVolume;
F32 mPan;
bool mSystemIsVistaOrHigher;
};
VolumeCatcherImpl::VolumeCatcherImpl()
: mVolume(1.0f), // default volume is max
mPan(0.f) // default pan is centered
{
}
VolumeCatcherImpl::~VolumeCatcherImpl()
{
}
void VolumeCatcherImpl::setVolume(F32 volume)
{
mVolume = volume;
// set both left/right to same volume
// TODO: use pan value to set independently
DWORD left_channel = (DWORD)(mVolume * 65535.0f);
DWORD right_channel = (DWORD)(mVolume * 65535.0f);
DWORD hw_volume = left_channel << 16 | right_channel;
::waveOutSetVolume(NULL, hw_volume);
}
void VolumeCatcherImpl::setPan(F32 pan)
{ // remember pan for calculating individual channel levels later
mPan = pan;
}
/////////////////////////////////////////////////////
VolumeCatcher::VolumeCatcher()
{
pimpl = VolumeCatcherImpl::getInstance();
}
VolumeCatcher::~VolumeCatcher()
{
// Let the instance persist until exit.
}
void VolumeCatcher::setVolume(F32 volume)
{
pimpl->setVolume(volume);
}
void VolumeCatcher::setPan(F32 pan)
{
pimpl->setPan(pan);
}
void VolumeCatcher::pump()
{
// No periodic tasks are necessary for this implementation.
}
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