| /* |
| * 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 blink { |
| |
| class AudioNodeOutput; |
| class DeferredTaskHandler; |
| |
| // An AudioSummingJunction represents a point where zero, one, or more AudioNodeOutputs connect. |
| |
| class AudioSummingJunction { |
| public: |
| virtual ~AudioSummingJunction(); |
| |
| // Can be called from any thread. |
| DeferredTaskHandler& deferredTaskHandler() const { |
| return *m_deferredTaskHandler; |
| } |
| |
| // 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 void didUpdate() = 0; |
| |
| protected: |
| explicit AudioSummingJunction(DeferredTaskHandler&); |
| |
| RefPtr<DeferredTaskHandler> m_deferredTaskHandler; |
| |
| // 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. |
| // These raw pointers are safe. Owner AudioNodes of these AudioNodeOutputs |
| // manage their lifetime, and AudioNode::dispose() disconnects all of |
| // connections. |
| 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. |
| // These raw pointers are safe. Owner of this AudioSummingJunction has |
| // strong references to owners of these AudioNodeOutput. |
| Vector<AudioNodeOutput*> m_renderingOutputs; |
| |
| // m_renderingStateNeedUpdating keeps track if m_outputs is modified. |
| bool m_renderingStateNeedUpdating; |
| }; |
| |
| } // namespace blink |
| |
| #endif // AudioSummingJunction_h |