OSDLAudioChannel.cc

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/* 
 * Copyright (C) 2003-2009 Olivier Boudeville
 *
 * This file is part of the OSDL library.
 *
 * The OSDL library is free software: you can redistribute it and/or modify
 * it under the terms of either the GNU Lesser General Public License or
 * the GNU General Public License, as they are published by the Free Software
 * Foundation, either version 3 of these Licenses, or (at your option) 
 * any later version.
 *
 * The OSDL 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 and the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License and of the GNU General Public License along with the OSDL library.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * Author: Olivier Boudeville (olivier.boudeville@esperide.com)
 *
 */


#include "OSDLAudioChannel.h"


#include "OSDLAudio.h"               // for getMixingChannelAt


#ifdef OSDL_USES_CONFIG_H
#include "OSDLConfig.h"              // for configure-time settings (SDL)
#endif // OSDL_USES_CONFIG_H

#if OSDL_ARCH_NINTENDO_DS
#include "OSDLConfigForNintendoDS.h" // for OSDL_USES_SDL and al
#endif // OSDL_ARCH_NINTENDO_DS


#if OSDL_USES_SDL
#include "SDL.h"                     // for SDL_InitSubSystem
#endif // OSDL_USES_SDL

#if OSDL_USES_SDL_MIXER
#include "SDL_mixer.h"               // for Mix_OpenAudio and al
#endif // OSDL_USES_SDL_MIXER



/*
 * Implementation notes: Mix_GetChunk not used as potentially unstable.
 * Groupings of mixer channels not integrated as not needed currently.
 *
 */

using std::string ;



using namespace Ceylan::Log ;

using namespace OSDL::Audio ;



AudioChannelException::AudioChannelException( const string & reason ) :
    AudioException( reason )
{

}



AudioChannelException::~AudioChannelException() throw()
{

}




AudioChannel::AudioChannel( ChannelNumber channelNumber ) :
    Ceylan::TextDisplayable(),
    _channelNumber( channelNumber )
{

#if OSDL_USES_SDL_MIXER

    // Registers callback-like method:
    
    ::Mix_ChannelFinished( HandleFinishedPlaybackCallback ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel constructor failed: "
        "no SDL_mixer support available." ) ;
    
#endif // OSDL_USES_SDL_MIXER
    
}   



AudioChannel::~AudioChannel() throw()
{
    
    // Nothing special to do.
        
}



ChannelNumber AudioChannel::getNumber() const
{

    return _channelNumber ;
        
}



Volume AudioChannel::getVolume() const
{

#if OSDL_USES_SDL_MIXER
    
    return static_cast<Volume>( ::Mix_Volume( _channelNumber, -1 ) ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::getVolume failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::setVolume( Volume newVolume ) 
{

#if OSDL_USES_SDL_MIXER
    
    ::Mix_Volume( _channelNumber, newVolume ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::setVolume failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER
        
}



void AudioChannel::setPanning( Ceylan::Maths::Percentage leftPercentage )
{

#if OSDL_USES_SDL_MIXER

    Ceylan::Uint8 left = static_cast<Ceylan::Uint8>( 
        ( leftPercentage * 254 ) / 100 ) ;
    
    if ( ::Mix_SetPanning( _channelNumber, left,
            /* right */ 254 - left ) == 0 )
        throw AudioChannelException( "AudioChannel::setPanning failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::setPanning failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}
    
                    
                    
void AudioChannel::unsetPanning()
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_SetPanning( _channelNumber, 255, 255 ) == 0 )
        throw AudioChannelException( "AudioChannel::unsetPanning failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::unsetPanning failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::setReverseStereo( bool reverse )
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_SetReverseStereo( _channelNumber, 
            ( ( reverse == true ) ? 1 : 0 ) ) == 0 )
        throw AudioException( "AudioChannel::setReverseStereo failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::setReverseStereo failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::setDistanceAttenuation( ListenerDistance distance ) 
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_SetDistance( _channelNumber, distance ) == 0 )
        throw AudioChannelException( 
            "AudioChannel::setDistanceAttenuation failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::setDistanceAttenuation failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::unsetDistanceAttenuation()
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_SetDistance( _channelNumber, 0 ) == 0 )
        throw AudioChannelException( 
            "AudioChannel::unsetDistanceAttenuation failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( 
        "AudioChannel::unsetDistanceAttenuation failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::setPositionAttenuation( ListenerDistance distance,
    ListenerAngle angle )
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_SetPosition( _channelNumber, distance, angle ) == 0 )
        throw AudioChannelException( 
            "AudioChannel::setPositionAttenuation failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::setPositionAttenuation failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::unsetPositionAttenuation()
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_SetPosition( _channelNumber, 0, 0 ) == 0 )
        throw AudioChannelException( 
            "AudioChannel::unsetPositionAttenuation failed: " 
            + string( ::Mix_GetError() ) ) ;
        
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( 
        "AudioChannel::unsetPositionAttenuation failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



bool AudioChannel::isPlaying() const
{

#if OSDL_USES_SDL_MIXER
    
    return ( ::Mix_Playing( _channelNumber ) != 0 ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::isPlaying failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER
        
}



bool AudioChannel::isPaused() const
{

#if OSDL_USES_SDL_MIXER
    
    return ( ::Mix_Paused( _channelNumber ) != 0 ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::isPaused failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



FadingStatus AudioChannel::getFadingStatus() const
{

#if OSDL_USES_SDL_MIXER
    
    switch( ::Mix_FadingChannel( _channelNumber ) )
    {
    
        case MIX_NO_FADING:
            return None ;
            break ; 
    
        case MIX_FADING_OUT:
            return Out ;
            break ; 
    
        case MIX_FADING_IN:
            return In ;
            break ; 
    
        default:
            LogPlug::error( 
                "AudioChannel::getFadingStatus: unexpected status" ) ;
            return None ;
            break ; 
                
    }
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::isPaused failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::pause()
{

#if OSDL_USES_SDL_MIXER
    
    ::Mix_Pause( _channelNumber ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::pause failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER
        
}



void AudioChannel::resume()
{

#if OSDL_USES_SDL_MIXER
    
    ::Mix_Resume( _channelNumber ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::resume failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER
        
}



void AudioChannel::waitEndOfPlayback() const
{

    while ( isPlaying() )
        Ceylan::System::atomicSleep() ;
        
}



void AudioChannel::halt()
{

#if OSDL_USES_SDL_MIXER
    
    ::Mix_HaltChannel( _channelNumber ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::halt failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER
        
}



void AudioChannel::expireIn( Ceylan::System::Millisecond expireDuration )
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_ExpireChannel( _channelNumber, expireDuration ) != 1 )
        throw AudioChannelException( "AudioChannel::expireIn failed: "
            + string( ::Mix_GetError() ) ) ;
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::expireIn failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}

    
                    
void AudioChannel::fadeOutDuring( Ceylan::System::Millisecond fadeOutDuration )
{

#if OSDL_USES_SDL_MIXER
    
    if ( ::Mix_FadeOutChannel( _channelNumber, fadeOutDuration ) != 1 )
        throw AudioChannelException( "AudioChannel::fadeOutDuring failed: "
            + string( ::Mix_GetError() ) ) ;
    
    
#else // OSDL_USES_SDL_MIXER

    throw AudioChannelException( "AudioChannel::fadeOutDuring failed: "
        "no SDL_mixer support available" ) ;
        
#endif // OSDL_USES_SDL_MIXER

}



void AudioChannel::onPlaybackFinished()         
{

    /*
     * Does nothing on purpose, meant to be overriden.
     *
     * @note Nevercall SDL_Mixer functions, nor SDL_LockAudio, from a callback
     * function.
     *
     */
     
}


        
const string AudioChannel::toString( Ceylan::VerbosityLevels level ) const
{
        
    return "Mixing channel #" + Ceylan::toString( _channelNumber ) ;
    
}





// Non-static method or classical function needed for call-back:
void AudioChannel::HandleFinishedPlaybackCallback( int channelNumber )
{

    try
    {
    
        OSDL::Audio::getExistingAudioModule().getMixingChannelAt(
            static_cast<ChannelNumber>( channelNumber ) ).onPlaybackFinished() ;
            
    }
    catch( const AudioException & e )
    {
    
        LogPlug::error( "AudioChannel::HandleFinishedPlaybackCallback failed: "
            + e.toString() ) ;
    
    }
    
}

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