Qt 4.8: GEInterfaces.cpp Example File (demos/mobile/quickhit/ga_src/GEInterfaces.cpp)

Qt Reference Documentation

# GEInterfaces.cpp Example File

demos/mobile/quickhit/ga_src/GEInterfaces.cpp

     /****************************************************************************
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     ** This file is part of the QtDeclarative module of the Qt Toolkit.
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     #include <memory.h>
     #include "GEInterfaces.h"

     using namespace GE;

     /**
      * CAudioSource
      * common functionality
      *
      */
     IAudioSource::IAudioSource() {
         m_next = 0;
     };

     IAudioSource::~IAudioSource() {

     };

     /**
      * CAudioMixer
      *
      */
     CAudioMixer::CAudioMixer() {
         m_sourceList = 0;
         m_mixingBuffer = 0;
         m_mixingBufferLength = 0;
         m_fixedGeneralVolume = 4096;
     };

     CAudioMixer::~CAudioMixer() {
         destroyList();
         if (m_mixingBuffer) {
             delete [] m_mixingBuffer;
             m_mixingBuffer = 0;
         };
     };

     void CAudioMixer::destroyList() {
         m_mutex.lock();
         IAudioSource *l = m_sourceList;
         while (l) {
             IAudioSource *n = l->m_next;
             delete l;
             l = n;
         };
         m_sourceList = 0;
         m_mutex.unlock();
     };

     IAudioSource* CAudioMixer::addAudioSource( IAudioSource *source ) {
         m_mutex.lock();
         source->m_next = 0;
         if (m_sourceList) {
             IAudioSource *l = m_sourceList;
             while (l->m_next) l = l->m_next;
             l->m_next = source;
         } else m_sourceList = source;
         m_mutex.unlock();
         return source;

     };

     bool CAudioMixer::removeAudioSource( IAudioSource *source ) {
         return true;
     };

     void CAudioMixer::setGeneralVolume( float vol ) {
         m_fixedGeneralVolume = (4096.0f*vol);
     };

     int CAudioMixer::pullAudio( AUDIO_SAMPLE_TYPE *target, int bufferLength ) {

         if (!m_sourceList) return 0;

         m_mutex.lock();

         if (m_mixingBufferLength<bufferLength) {
             if (m_mixingBuffer) delete [] m_mixingBuffer;
             m_mixingBufferLength = bufferLength;
             m_mixingBuffer = new AUDIO_SAMPLE_TYPE[ m_mixingBufferLength ];
         };

         memset( target, 0, sizeof( AUDIO_SAMPLE_TYPE ) * bufferLength );

         AUDIO_SAMPLE_TYPE *t;
         AUDIO_SAMPLE_TYPE *t_target;
         AUDIO_SAMPLE_TYPE *s;

         IAudioSource *prev = 0;
         IAudioSource *l = m_sourceList;
         while (l) {
             IAudioSource *next = l->m_next;

                 // process l
             int mixed = l->pullAudio( m_mixingBuffer, bufferLength );
             if (mixed>0) {
                 // mix to main..
                 t = target;
                 t_target = t+mixed;
                 s = m_mixingBuffer;
                 while (t!=t_target) {
                     *t +=(((*s)*m_fixedGeneralVolume)>>12);
                     t++;
                     s++;
                 };
             };

             // autodestroy
             if (l->canBeDestroyed() == true) {          // NOTE, IS UNDER TESTING,... MIGHT CAUSE UNPREDICTABLE CRASHING WITH SOME USE CASES!!!
                 if (!prev)
                     m_sourceList = next;
                 else prev->m_next = next;
                 delete l;
                 l = 0;
             };

             prev = l;
             l = next;
         };
         m_mutex.unlock();
         return bufferLength;
     };