1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/media/webaudio/AudioParamTimeline.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,100 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim:set ts=2 sw=2 sts=2 et cindent: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef AudioParamTimeline_h_
1.11 +#define AudioParamTimeline_h_
1.12 +
1.13 +#include "AudioEventTimeline.h"
1.14 +#include "mozilla/ErrorResult.h"
1.15 +#include "nsAutoPtr.h"
1.16 +#include "MediaStreamGraph.h"
1.17 +#include "AudioSegment.h"
1.18 +
1.19 +namespace mozilla {
1.20 +
1.21 +namespace dom {
1.22 +
1.23 +// This helper class is used to represent the part of the AudioParam
1.24 +// class that gets sent to AudioNodeEngine instances. In addition to
1.25 +// AudioEventTimeline methods, it holds a pointer to an optional
1.26 +// MediaStream which represents the AudioNode inputs to the AudioParam.
1.27 +// This MediaStream is managed by the AudioParam subclass on the main
1.28 +// thread, and can only be obtained from the AudioNodeEngine instances
1.29 +// consuming this class.
1.30 +class AudioParamTimeline : public AudioEventTimeline<ErrorResult>
1.31 +{
1.32 + typedef AudioEventTimeline<ErrorResult> BaseClass;
1.33 +
1.34 +public:
1.35 + explicit AudioParamTimeline(float aDefaultValue)
1.36 + : BaseClass(aDefaultValue)
1.37 + {
1.38 + }
1.39 +
1.40 + MediaStream* Stream() const
1.41 + {
1.42 + return mStream;
1.43 + }
1.44 +
1.45 + bool HasSimpleValue() const
1.46 + {
1.47 + return BaseClass::HasSimpleValue() && !mStream;
1.48 + }
1.49 +
1.50 + // Get the value of the AudioParam at time aTime + aCounter.
1.51 + // aCounter here is an offset to aTime if we try to get the value in ticks,
1.52 + // otherwise it should always be zero. aCounter is meant to be used when
1.53 + // getting the value of an a-rate AudioParam for each tick inside an
1.54 + // AudioNodeEngine implementation.
1.55 + template<class TimeType>
1.56 + float GetValueAtTime(TimeType aTime, size_t aCounter = 0);
1.57 +
1.58 + virtual size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
1.59 + {
1.60 + return mStream ? mStream->SizeOfIncludingThis(aMallocSizeOf) : 0;
1.61 + }
1.62 +
1.63 + virtual size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
1.64 + {
1.65 + return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
1.66 + }
1.67 +
1.68 +
1.69 +private:
1.70 + float AudioNodeInputValue(size_t aCounter) const;
1.71 +
1.72 +protected:
1.73 + // This is created lazily when needed.
1.74 + nsRefPtr<MediaStream> mStream;
1.75 +};
1.76 +
1.77 +template<> inline float
1.78 +AudioParamTimeline::GetValueAtTime(double aTime, size_t aCounter)
1.79 +{
1.80 + MOZ_ASSERT(!aCounter);
1.81 +
1.82 + // Getting an AudioParam value on an AudioNode does not consider input from
1.83 + // other AudioNodes, which is managed only on the graph thread.
1.84 + return BaseClass::GetValueAtTime(aTime);
1.85 +}
1.86 +
1.87 +
1.88 +template<> inline float
1.89 +AudioParamTimeline::GetValueAtTime(int64_t aTime, size_t aCounter)
1.90 +{
1.91 + MOZ_ASSERT(aCounter < WEBAUDIO_BLOCK_SIZE);
1.92 + MOZ_ASSERT(!aCounter || !HasSimpleValue());
1.93 +
1.94 + // Mix the value of the AudioParam itself with that of the AudioNode inputs.
1.95 + return BaseClass::GetValueAtTime(static_cast<int64_t>(aTime + aCounter)) +
1.96 + (mStream ? AudioNodeInputValue(aCounter) : 0.0f);
1.97 +}
1.98 +
1.99 +}
1.100 +}
1.101 +
1.102 +#endif
1.103 +
