AudioBus* AudioNodeInput::pull(AudioBus* inPlaceBus, size_t framesToProcess)
{
ASSERT(context()->isAudioThread());
// Handle single connection case.
if (numberOfRenderingConnections() == 1 && node()->internalChannelCountMode() == AudioNode::Max) {
// The output will optimize processing using inPlaceBus if it's able.
AudioNodeOutput* output = this->renderingOutput(0);
return output->pull(inPlaceBus, framesToProcess);
}
AudioBus* internalSummingBus = this->internalSummingBus();
if (!numberOfRenderingConnections()) {
// At least, generate silence if we're not connected to anything.
// FIXME: if we wanted to get fancy, we could propagate a 'silent hint' here to optimize the downstream graph processing.
internalSummingBus->zero();
return internalSummingBus;
}
// Handle multiple connections case.
sumAllConnections(internalSummingBus, framesToProcess);
return internalSummingBus;
}
void AudioNodeInput::sumAllConnections(AudioBus* summingBus, size_t framesToProcess)
{
ASSERT(context()->isAudioThread());
// We shouldn't be calling this method if there's only one connection, since it's less efficient.
ASSERT(numberOfRenderingConnections() > 1 || node()->internalChannelCountMode() != AudioNode::Max);
ASSERT(summingBus);
if (!summingBus)
return;
summingBus->zero();
AudioBus::ChannelInterpretation interpretation = node()->internalChannelInterpretation();
for (unsigned i = 0; i < numberOfRenderingConnections(); ++i) {
AudioNodeOutput* output = renderingOutput(i);
ASSERT(output);
// Render audio from this output.
AudioBus* connectionBus = output->pull(0, framesToProcess);
// Sum, with unity-gain.
summingBus->sumFrom(*connectionBus, interpretation);
}
}
void PannerNode::notifyAudioSourcesConnectedToNode(ContextRenderLock& r, AudioNode* node)
{
ASSERT(node);
if (!node)
return;
// First check if this node is an AudioBufferSourceNode. If so, let it know about us so that doppler shift pitch can be taken into account.
if (node->nodeType() == NodeTypeAudioBufferSource)
{
AudioBufferSourceNode* bufferSourceNode = reinterpret_cast<AudioBufferSourceNode*>(node);
bufferSourceNode->setPannerNode(this);
}
else
{
// Go through all inputs to this node.
for (unsigned i = 0; i < node->numberOfInputs(); ++i)
{
auto input = node->input(i);
// For each input, go through all of its connections, looking for AudioBufferSourceNodes.
for (unsigned j = 0; j < input->numberOfRenderingConnections(r); ++j)
{
auto connectedOutput = input->renderingOutput(r, j);
AudioNode* connectedNode = connectedOutput->node();
notifyAudioSourcesConnectedToNode(r, connectedNode); // recurse
}
}
}
}
void AudioParam::calculateFinalValues(ContextRenderLock& r, float* values, unsigned numberOfValues, bool sampleAccurate)
{
bool isSafe = r.context() && values && numberOfValues;
if (!isSafe)
return;
// The calculated result will be the "intrinsic" value summed with all audio-rate connections.
if (sampleAccurate) {
// Calculate sample-accurate (a-rate) intrinsic values.
calculateTimelineValues(r, values, numberOfValues);
}
else {
// Calculate control-rate (k-rate) intrinsic value.
bool hasValue;
float timelineValue = m_timeline.valueForContextTime(r, narrowPrecisionToFloat(m_value), hasValue);
if (hasValue)
m_value = timelineValue;
values[0] = narrowPrecisionToFloat(m_value);
}
// if there are rendering connections, be sure they are ready
updateRenderingState(r);
size_t connectionCount = numberOfRenderingConnections(r);
if (!connectionCount)
return;
// Now sum all of the audio-rate connections together (unity-gain summing junction).
// Note that parameter connections would normally be mono, so mix down to mono if necessary.
// LabSound: For some reason a bus was temporarily created here and the results discarded.
// Bug still exists in WebKit top of tree.
//
if (m_data->m_internalSummingBus && m_data->m_internalSummingBus->length() < numberOfValues)
m_data->m_internalSummingBus.reset();
if (!m_data->m_internalSummingBus)
m_data->m_internalSummingBus.reset(new AudioBus(1, numberOfValues));
// point the summing bus at the values array
m_data->m_internalSummingBus->setChannelMemory(0, values, numberOfValues);
for (size_t i = 0; i < connectionCount; ++i) {
auto output = renderingOutput(r, i);
if (!output)
continue;
// Render audio from this output.
AudioBus* connectionBus = output->pull(r, 0, AudioNode::ProcessingSizeInFrames);
// Sum, with unity-gain.
m_data->m_internalSummingBus->sumFrom(*connectionBus);
}
}
AudioBus* AudioNodeInput::bus()
{
ASSERT(context()->isAudioThread());
// Handle single connection specially to allow for in-place processing.
if (numberOfRenderingConnections() == 1 && node()->internalChannelCountMode() == AudioNode::Max)
return renderingOutput(0)->bus();
// Multiple connections case or complex ChannelCountMode (or no connections).
return internalSummingBus();
}
AudioBus* AudioNodeInput::bus() {
DCHECK(deferredTaskHandler().isAudioThread());
// Handle single connection specially to allow for in-place processing.
if (numberOfRenderingConnections() == 1 &&
handler().internalChannelCountMode() == AudioHandler::Max)
return renderingOutput(0)->bus();
// Multiple connections case or complex ChannelCountMode (or no connections).
return internalSummingBus();
}
unsigned AudioNodeInput::numberOfRenderingChannels()
{
ASSERT(context()->isAudioThread());
// Find the number of channels of the rendering connection with the largest number of channels.
unsigned maxChannels = 1; // one channel is the minimum allowed
for (unsigned i = 0; i < numberOfRenderingConnections(); ++i)
maxChannels = max(maxChannels, renderingOutput(i)->bus()->numberOfChannels());
return maxChannels;
}
void AudioParam::calculateFinalValues(float* values, unsigned numberOfValues, bool sampleAccurate)
{
bool isGood = context() && context()->isAudioThread() && values && numberOfValues;
ASSERT(isGood);
if (!isGood)
return;
// The calculated result will be the "intrinsic" value summed with all audio-rate connections.
if (sampleAccurate) {
// Calculate sample-accurate (a-rate) intrinsic values.
calculateTimelineValues(values, numberOfValues);
} else {
// Calculate control-rate (k-rate) intrinsic value.
bool hasValue;
float timelineValue = m_timeline.valueForContextTime(context(), narrowPrecisionToFloat(m_value), hasValue);
if (hasValue)
m_value = timelineValue;
values[0] = narrowPrecisionToFloat(m_value);
}
// Now sum all of the audio-rate connections together (unity-gain summing junction).
// Note that connections would normally be mono, but we mix down to mono if necessary.
RefPtr<AudioBus> summingBus = AudioBus::create(1, numberOfValues, false);
summingBus->setChannelMemory(0, values, numberOfValues);
for (unsigned i = 0; i < numberOfRenderingConnections(); ++i) {
AudioNodeOutput* output = renderingOutput(i);
ASSERT(output);
// Render audio from this output.
AudioBus* connectionBus = output->pull(0, AudioNode::ProcessingSizeInFrames);
// Sum, with unity-gain.
summingBus->sumFrom(*connectionBus);
}
}