1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
/*
* Copyright (C) 2012, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef AudioSummingJunction_h
#define AudioSummingJunction_h
#include "platform/audio/AudioBus.h"
#include "platform/heap/Handle.h"
#include "wtf/HashSet.h"
#include "wtf/Vector.h"
namespace WebCore {
class AudioContext;
class AudioNodeOutput;
// An AudioSummingJunction represents a point where zero, one, or more AudioNodeOutputs connect.
class AudioSummingJunction {
public:
explicit AudioSummingJunction(AudioContext*);
virtual ~AudioSummingJunction();
// Can be called from any thread.
AudioContext* context() { return m_context.get(); }
// This must be called whenever we modify m_outputs.
void changedOutputs();
// This copies m_outputs to m_renderingOutputs. Please see comments for these lists below.
// This must be called when we own the context's graph lock in the audio thread at the very start or end of the render quantum.
void updateRenderingState();
// Rendering code accesses its version of the current connections here.
unsigned numberOfRenderingConnections() const { return m_renderingOutputs.size(); }
AudioNodeOutput* renderingOutput(unsigned i) { return m_renderingOutputs[i]; }
bool isConnected() const { return numberOfRenderingConnections() > 0; }
virtual bool canUpdateState() = 0;
virtual void didUpdate() = 0;
protected:
RefPtrWillBePersistent<AudioContext> m_context;
// m_outputs contains the AudioNodeOutputs representing current connections which are not disabled.
// The rendering code should never use this directly, but instead uses m_renderingOutputs.
HashSet<AudioNodeOutput*> m_outputs;
// m_renderingOutputs is a copy of m_outputs which will never be modified during the graph rendering on the audio thread.
// This is the list which is used by the rendering code.
// Whenever m_outputs is modified, the context is told so it can later update m_renderingOutputs from m_outputs at a safe time.
// Most of the time, m_renderingOutputs is identical to m_outputs.
Vector<AudioNodeOutput*> m_renderingOutputs;
// m_renderingStateNeedUpdating keeps track if m_outputs is modified.
bool m_renderingStateNeedUpdating;
};
} // namespace WebCore
#endif // AudioSummingJunction_h
|
