C++ LLAudioSource::update方法代码示例

void LLAudioEngine::idle(F32 max_decode_time)
{
	if (max_decode_time <= 0.f)
	{
		max_decode_time = default_max_decode_time;
	}
	
	// "Update" all of our audio sources, clean up dead ones.
	// Primarily does position updating, cleanup of unused audio sources.
	// Also does regeneration of the current priority of each audio source.

	S32 i;
	for (i = 0; i < MAX_BUFFERS; i++)
	{
		if (mBuffers[i])
		{
			mBuffers[i]->mInUse = false;
		}
	}

	F32 max_priority = -1.f;
	LLAudioSource *max_sourcep = NULL; // Maximum priority source without a channel
	source_map::iterator iter;
	for (iter = mAllSources.begin(); iter != mAllSources.end();)
	{
		LLAudioSource *sourcep = iter->second;

		// Update this source
		sourcep->update();
		sourcep->updatePriority();

		if (sourcep->isDone())
		{
			// The source is done playing, clean it up.
			delete sourcep;
			mAllSources.erase(iter++);
			continue;
		}

		if (sourcep->isMuted())
		{
			++iter;
		  	continue;
		}

		if (!sourcep->getChannel() && sourcep->getCurrentBuffer())
		{
			// We could potentially play this sound if its priority is high enough.
			if (sourcep->getPriority() > max_priority)
			{
				max_priority = sourcep->getPriority();
				max_sourcep = sourcep;
			}
		}

		// Move on to the next source
		iter++;
	}

	// Now, do priority-based organization of audio sources.
	// All channels used, check priorities.
	// Find channel with lowest priority
	if (max_sourcep)
	{
		LLAudioChannel *channelp = getFreeChannel(max_priority);
		if (channelp)
		{
			//llinfos << "Replacing source in channel due to priority!" << llendl;
			max_sourcep->setChannel(channelp);
			channelp->setSource(max_sourcep);
			if (max_sourcep->isSyncSlave())
			{
				// A sync slave, it doesn't start playing until it's synced up with the master.
				// Flag this channel as waiting for sync, and return true.
				channelp->setWaiting(true);
			}
			else
			{
				channelp->setWaiting(false);
				channelp->play();
			}
		}
	}

	
	// Do this BEFORE we update the channels
	// Update the channels to sync up with any changes that the source made,
	// such as changing what sound was playing.
	updateChannels();

	// Update queued sounds (switch to next queued data if the current has finished playing)
	for (iter = mAllSources.begin(); iter != mAllSources.end(); ++iter)
	{
		// This is lame, instead of this I could actually iterate through all the sources
		// attached to each channel, since only those with active channels
		// can have anything interesting happen with their queue? (Maybe not true)
		LLAudioSource *sourcep = iter->second;
		if (!sourcep->mQueuedDatap || sourcep->isMuted())
		{
			// Muted, or nothing queued, so we don't care.
//.........这里部分代码省略.........

void LLAudioEngine::idle(F32 max_decode_time)
{
	if (max_decode_time <= 0.f)
	{
		max_decode_time = default_max_decode_time;
	}
	
	// "Update" all of our audio sources, clean up dead ones.
	// Primarily does position updating, cleanup of unused audio sources.
	// Also does regeneration of the current priority of each audio source.

	S32 i;
	for (i = 0; i < MAX_BUFFERS; i++)
	{
		if (mBuffers[i])
		{
			mBuffers[i]->mInUse = false;
		}
	}

	//Iterate down all queued sources. Remove finished ones, sort active ones by priority. Find highest priority 'master' source if present.
	LLAudioSource *sync_masterp = NULL;	//Highest priority syncmaster
	LLAudioSource *sync_slavep = NULL;	//Highest priority syncslave

	//Priority queue that will be filled with soundsources that have a high likeleyhood of being able to start [re]playing this idle tick.
	//Sort order:  Primary: priority. Secondary: syncmaster. Tertiary: syncslave
	std::priority_queue<LLAudioSource*,std::vector<LLAudioSource*,boost::pool_allocator<LLAudioSource*> >,SourcePriorityComparator> queue;

	//Have to put syncslaves into a temporary list until the syncmaster state is determined.
	//If the syncmaster might be started, or just looped, insert all pending/looping syncslaves into the priority queue.
	//If the there is no active syncmaster, then stop any currently looping syncslaves and add none to the priority queue.
	//This is necessary as any looping soundsources to be stopped, MUST be stopped before iterating down the priority queue.
	static std::vector<LLAudioSource*> slave_list;	
	slave_list.clear();

	//Iterate over all sources. Update their decode or 'done' state, as well as their priorities.
	//Also add sources that might be able to start playing to the priority queue.
	//Only sources without channels should be added to priority queue.
	//Syncslaves must put into the slave list instead of the priority queue.
	for (source_map::iterator iter = mAllSources.begin(); iter != mAllSources.end();)
	{
		LLAudioSource *sourcep = iter->second;

		//Load/decode/queue pop
		sourcep->update();

		//Done after update, as failure to load might mark source as corrupt, which causes isDone to return true.
		if (sourcep->isDone())		
		{
			// The source is done playing, clean it up.
			delete sourcep;
			mAllSources.erase(iter++);
			continue;
		}

		// Increment iter here (it is not used anymore), so we can use continue below to move on to the next source.
		++iter;

		if(!sourcep->isLoop() && sourcep->mPlayedOnce && (!sourcep->mChannelp || !sourcep->mChannelp->isPlaying()))
		{
			continue;
		}

		LLAudioData *adp = sourcep->getCurrentData();
		//If there is no current data at all, or if it hasn't loaded, we must skip this source.
		if (!adp || !adp->getBuffer())
		{
			continue;
		}

		sourcep->updatePriority();	//Calculates current priority. 1.f=ambient. 0.f=muted. Otherwise based off of distance.

		if (sourcep->getPriority() < F_APPROXIMATELY_ZERO)
		{
			// Muted, or nothing queued, or too far, so we don't care.
			continue;
		}
		else if(sourcep->isSyncMaster())
		{
			if(!sync_masterp || sourcep->getPriority() > sync_masterp->getPriority())
			{
				if(sync_masterp && !sync_masterp->getChannel())
					queue.push(sync_masterp);	//Add lower-priority soundmaster to the queue as a normal sound.	
				sync_masterp = sourcep;
				//Don't add master to the queue yet.
				//Add it after highest-priority sound slave is found so we can outrank its priority.
				continue;	
			}
			//Else fall through like a normal sound.
		}
		else if(sourcep->isSyncSlave())
		{
			if(!sync_slavep || sourcep->getPriority() > sync_slavep->getPriority())
			{
				sync_slavep = sourcep;
			}
			//Don't add to the priority queue quite yet. Best primary syncmaster candidate may not have been determined yet.
			slave_list.push_back(sourcep);
			continue;
		}
//.........这里部分代码省略.........