| // Copyright 2016 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "third_party/blink/renderer/modules/webaudio/constant_source_node.h" |
| |
| #include <algorithm> |
| |
| #include "third_party/blink/renderer/modules/webaudio/audio_node_output.h" |
| #include "third_party/blink/renderer/modules/webaudio/constant_source_options.h" |
| #include "third_party/blink/renderer/platform/audio/audio_utilities.h" |
| #include "third_party/blink/renderer/platform/bindings/exception_state.h" |
| #include "third_party/blink/renderer/platform/wtf/math_extras.h" |
| #include "third_party/blink/renderer/platform/wtf/std_lib_extras.h" |
| |
| namespace blink { |
| |
| ConstantSourceHandler::ConstantSourceHandler(AudioNode& node, |
| float sample_rate, |
| AudioParamHandler& offset) |
| : AudioScheduledSourceHandler(kNodeTypeConstantSource, node, sample_rate), |
| offset_(&offset), |
| sample_accurate_values_(audio_utilities::kRenderQuantumFrames) { |
| // A ConstantSource is always mono. |
| AddOutput(1); |
| |
| Initialize(); |
| } |
| |
| scoped_refptr<ConstantSourceHandler> ConstantSourceHandler::Create( |
| AudioNode& node, |
| float sample_rate, |
| AudioParamHandler& offset) { |
| return base::AdoptRef(new ConstantSourceHandler(node, sample_rate, offset)); |
| } |
| |
| ConstantSourceHandler::~ConstantSourceHandler() { |
| Uninitialize(); |
| } |
| |
| void ConstantSourceHandler::Process(uint32_t frames_to_process) { |
| AudioBus* output_bus = Output(0).Bus(); |
| DCHECK(output_bus); |
| |
| if (!IsInitialized() || !output_bus->NumberOfChannels()) { |
| output_bus->Zero(); |
| return; |
| } |
| |
| // The audio thread can't block on this lock, so we call tryLock() instead. |
| MutexTryLocker try_locker(process_lock_); |
| if (!try_locker.Locked()) { |
| // Too bad - the tryLock() failed. |
| output_bus->Zero(); |
| return; |
| } |
| |
| size_t quantum_frame_offset; |
| size_t non_silent_frames_to_process; |
| double start_frame_offset; |
| |
| // Figure out where in the current rendering quantum that the source is |
| // active and for how many frames. |
| std::tie(quantum_frame_offset, non_silent_frames_to_process, |
| start_frame_offset) = |
| UpdateSchedulingInfo(frames_to_process, output_bus); |
| |
| if (!non_silent_frames_to_process) { |
| output_bus->Zero(); |
| return; |
| } |
| |
| if (offset_->HasSampleAccurateValues()) { |
| DCHECK_LE(frames_to_process, sample_accurate_values_.size()); |
| if (frames_to_process <= sample_accurate_values_.size()) { |
| float* offsets = sample_accurate_values_.Data(); |
| offset_->CalculateSampleAccurateValues(offsets, frames_to_process); |
| if (non_silent_frames_to_process > 0) { |
| memcpy(output_bus->Channel(0)->MutableData() + quantum_frame_offset, |
| offsets + quantum_frame_offset, |
| non_silent_frames_to_process * sizeof(*offsets)); |
| output_bus->ClearSilentFlag(); |
| } else { |
| output_bus->Zero(); |
| } |
| } |
| } else { |
| float value = offset_->Value(); |
| |
| if (value == 0) { |
| output_bus->Zero(); |
| } else { |
| float* dest = output_bus->Channel(0)->MutableData(); |
| dest += quantum_frame_offset; |
| for (unsigned k = 0; k < non_silent_frames_to_process; ++k) { |
| dest[k] = value; |
| } |
| output_bus->ClearSilentFlag(); |
| } |
| } |
| } |
| |
| bool ConstantSourceHandler::PropagatesSilence() const { |
| return !IsPlayingOrScheduled() || HasFinished(); |
| } |
| |
| // ---------------------------------------------------------------- |
| ConstantSourceNode::ConstantSourceNode(BaseAudioContext& context) |
| : AudioScheduledSourceNode(context), |
| offset_(AudioParam::Create( |
| context, |
| kParamTypeConstantSourceOffset, |
| 1, |
| AudioParamHandler::AutomationRate::kAudio, |
| AudioParamHandler::AutomationRateMode::kVariable)) { |
| SetHandler(ConstantSourceHandler::Create(*this, context.sampleRate(), |
| offset_->Handler())); |
| } |
| |
| ConstantSourceNode* ConstantSourceNode::Create( |
| BaseAudioContext& context, |
| ExceptionState& exception_state) { |
| DCHECK(IsMainThread()); |
| |
| if (context.IsContextClosed()) { |
| context.ThrowExceptionForClosedState(exception_state); |
| return nullptr; |
| } |
| |
| return MakeGarbageCollected<ConstantSourceNode>(context); |
| } |
| |
| ConstantSourceNode* ConstantSourceNode::Create( |
| BaseAudioContext* context, |
| const ConstantSourceOptions* options, |
| ExceptionState& exception_state) { |
| DCHECK(IsMainThread()); |
| |
| ConstantSourceNode* node = Create(*context, exception_state); |
| |
| if (!node) |
| return nullptr; |
| |
| node->offset()->setValue(options->offset()); |
| |
| return node; |
| } |
| |
| void ConstantSourceNode::Trace(blink::Visitor* visitor) { |
| visitor->Trace(offset_); |
| AudioScheduledSourceNode::Trace(visitor); |
| } |
| |
| ConstantSourceHandler& ConstantSourceNode::GetConstantSourceHandler() const { |
| return static_cast<ConstantSourceHandler&>(Handler()); |
| } |
| |
| AudioParam* ConstantSourceNode::offset() { |
| return offset_; |
| } |
| |
| } // namespace blink |