Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

1 files changed, 100 insertions, 0 deletions

diff --git a/Source/WebCore/webaudio/AudioParam.h b/Source/WebCore/webaudio/AudioParam.h
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+++ b/Source/WebCore/webaudio/AudioParam.h
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+/*
+ * Copyright (C) 2010 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.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE 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 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 AudioParam_h
+#define AudioParam_h
+
+#include "PlatformString.h"
+#include <sys/types.h>
+#include <wtf/PassRefPtr.h>
+#include <wtf/RefCounted.h>
+
+namespace WebCore {
+
+class AudioParam : public RefCounted<AudioParam> {
+public:
+    static const double DefaultSmoothingConstant;
+    static const double SnapThreshold;
+
+    static PassRefPtr<AudioParam> create(const String& name, double defaultValue, double minValue, double maxValue, unsigned units = 0)
+    {
+        return adoptRef(new AudioParam(name, defaultValue, minValue, maxValue, units));
+    }
+
+    AudioParam(const String& name, double defaultValue, double minValue, double maxValue, unsigned units = 0)
+        : m_name(name)
+        , m_value(defaultValue)
+        , m_defaultValue(defaultValue)
+        , m_minValue(minValue)
+        , m_maxValue(maxValue)
+        , m_units(units)
+        , m_smoothedValue(defaultValue)
+        , m_smoothingConstant(DefaultSmoothingConstant)
+    {
+    }
+
+    float value() const { return static_cast<float>(m_value); }
+    
+    void setValue(float);
+
+    String name() const { return m_name; }
+
+    float minValue() const { return static_cast<float>(m_minValue); }
+    float maxValue() const { return static_cast<float>(m_maxValue); }
+    float defaultValue() const { return static_cast<float>(m_defaultValue); }
+    unsigned units() const { return m_units; }
+
+    // Value smoothing:
+
+    // When a new value is set with setValue(), in our internal use of the parameter we don't immediately jump to it.
+    // Instead we smoothly approach this value to avoid glitching.
+    float smoothedValue() const { return static_cast<float>(m_smoothedValue); }
+
+    // Smoothly exponentially approaches to (de-zippers) the desired value.
+    // Returns true if smoothed value has already snapped exactly to value.
+    bool smooth();
+
+    void resetSmoothedValue() { m_smoothedValue = m_value; }
+    void setSmoothingConstant(double k) { m_smoothingConstant = k; }
+
+private:
+    String m_name;
+    double m_value;
+    double m_defaultValue;
+    double m_minValue;
+    double m_maxValue;
+    unsigned m_units;
+
+    // Smoothing (de-zippering)
+    double m_smoothedValue;
+    double m_smoothingConstant;
+};
+
+} // namespace WebCore
+
+#endif // AudioParam_h