gecko/content/media/webaudio/AudioParam.cpp

151 lines
4.4 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "AudioParam.h"
#include "nsContentUtils.h"
#include "nsIDOMWindow.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/dom/AudioParamBinding.h"
#include "AudioNodeEngine.h"
#include "AudioNodeStream.h"
namespace mozilla {
namespace dom {
NS_IMPL_CYCLE_COLLECTION_CLASS(AudioParam)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(AudioParam)
tmp->DisconnectFromGraphAndDestroyStream();
NS_IMPL_CYCLE_COLLECTION_UNLINK(mNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(AudioParam)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCACHE(AudioParam)
NS_IMPL_CYCLE_COLLECTING_NATIVE_ADDREF(AudioParam)
NS_IMETHODIMP_(nsrefcnt)
AudioParam::Release()
{
if (mRefCnt.get() == 1) {
// We are about to be deleted, disconnect the object from the graph before
// the derived type is destroyed.
DisconnectFromGraphAndDestroyStream();
}
NS_IMPL_CC_NATIVE_RELEASE_BODY(AudioParam)
}
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(AudioParam, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(AudioParam, Release)
AudioParam::AudioParam(AudioNode* aNode,
AudioParam::CallbackType aCallback,
float aDefaultValue)
: AudioParamTimeline(aDefaultValue)
, mNode(aNode)
, mCallback(aCallback)
, mDefaultValue(aDefaultValue)
{
SetIsDOMBinding();
}
AudioParam::~AudioParam()
{
MOZ_ASSERT(mInputNodes.IsEmpty());
}
JSObject*
AudioParam::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aScope)
{
return AudioParamBinding::Wrap(aCx, aScope, this);
}
void
AudioParam::DisconnectFromGraphAndDestroyStream()
{
// Addref this temporarily so the refcount bumping below doesn't destroy us
// prematurely
nsRefPtr<AudioParam> kungFuDeathGrip = this;
while (!mInputNodes.IsEmpty()) {
uint32_t i = mInputNodes.Length() - 1;
nsRefPtr<AudioNode> input = mInputNodes[i].mInputNode;
mInputNodes.RemoveElementAt(i);
input->RemoveOutputParam(this);
}
if (mNodeStreamPort) {
mNodeStreamPort->Destroy();
mNodeStreamPort = nullptr;
}
if (mStream) {
mStream->Destroy();
mStream = nullptr;
}
}
MediaStream*
AudioParam::Stream()
{
if (mStream) {
return mStream;
}
AudioNodeEngine* engine = new AudioNodeEngine(nullptr);
nsRefPtr<AudioNodeStream> stream =
mNode->Context()->Graph()->CreateAudioNodeStream(engine,
MediaStreamGraph::INTERNAL_STREAM,
Node()->Context()->SampleRate());
// Force the input to have only one channel, and make it down-mix using
// the speaker rules if needed.
stream->SetChannelMixingParametersImpl(1, ChannelCountMode::Explicit, ChannelInterpretation::Speakers);
// Mark as an AudioParam helper stream
stream->SetAudioParamHelperStream();
mStream = stream.forget();
// Setup the AudioParam's stream as an input to the owner AudioNode's stream
MediaStream* nodeStream = mNode->Stream();
MOZ_ASSERT(nodeStream->AsProcessedStream());
ProcessedMediaStream* ps = static_cast<ProcessedMediaStream*>(nodeStream);
mNodeStreamPort = ps->AllocateInputPort(mStream, MediaInputPort::FLAG_BLOCK_INPUT);
// Let the MSG's copy of AudioParamTimeline know about the change in the stream
mCallback(mNode);
return mStream;
}
float
AudioParamTimeline::AudioNodeInputValue(size_t aCounter) const
{
MOZ_ASSERT(mStream);
// If we have a chunk produced by the AudioNode inputs to the AudioParam,
// get its value now. We use aCounter to tell us which frame of the last
// AudioChunk to look at.
float audioNodeInputValue = 0.0f;
const AudioChunk& lastAudioNodeChunk =
static_cast<AudioNodeStream*>(mStream.get())->LastChunks()[0];
if (!lastAudioNodeChunk.IsNull()) {
MOZ_ASSERT(lastAudioNodeChunk.GetDuration() == WEBAUDIO_BLOCK_SIZE);
audioNodeInputValue =
static_cast<const float*>(lastAudioNodeChunk.mChannelData[0])[aCounter];
}
return audioNodeInputValue;
}
}
}