git subrepo clone --branch=sono6good https://github.com/essej/JUCE.git deps/juce

subrepo:
  subdir:   "deps/juce"
  merged:   "b13f9084e"
upstream:
  origin:   "https://github.com/essej/JUCE.git"
  branch:   "sono6good"
  commit:   "b13f9084e"
git-subrepo:
  version:  "0.4.3"
  origin:   "https://github.com/ingydotnet/git-subrepo.git"
  commit:   "2f68596"

deps/juce/modules/juce_gui_basics/layout/juce_AnimatedPosition.h

@@ -0,0 +1,207 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library.
+   Copyright (c) 2020 - Raw Material Software Limited
+
+   JUCE is an open source library subject to commercial or open-source
+   licensing.
+
+   By using JUCE, you agree to the terms of both the JUCE 6 End-User License
+   Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).
+
+   End User License Agreement: www.juce.com/juce-6-licence
+   Privacy Policy: www.juce.com/juce-privacy-policy
+
+   Or: You may also use this code under the terms of the GPL v3 (see
+   www.gnu.org/licenses).
+
+   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
+   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
+   DISCLAIMED.
+
+  ==============================================================================
+*/
+
+namespace juce
+{
+
+//==============================================================================
+/**
+    Models a 1-dimensional position that can be dragged around by the user, and which
+    will then continue moving with a customisable physics behaviour when released.
+
+    This is useful for things like scrollable views or objects that can be dragged and
+    thrown around with the mouse/touch, and by writing your own behaviour class, you can
+    customise the trajectory that it follows when released.
+
+    The class uses its own Timer to continuously change its value when a drag ends, and
+    Listener objects can be registered to receive callbacks whenever the value changes.
+
+    The value is stored as a double, and can be used to represent whatever units you need.
+
+    The template parameter Behaviour must be a class that implements various methods to
+    return the physics of the value's movement - you can use the classes provided for this
+    in the AnimatedPositionBehaviours namespace, or write your own custom behaviour.
+
+    @see AnimatedPositionBehaviours::ContinuousWithMomentum,
+         AnimatedPositionBehaviours::SnapToPageBoundaries
+
+    @tags{GUI}
+*/
+template <typename Behaviour>
+class AnimatedPosition  : private Timer
+{
+public:
+    AnimatedPosition()
+        :  range (-std::numeric_limits<double>::max(),
+                   std::numeric_limits<double>::max())
+    {
+    }
+
+    /** Sets a range within which the value will be constrained. */
+    void setLimits (Range<double> newRange) noexcept
+    {
+        range = newRange;
+    }
+
+    //==============================================================================
+    /** Called to indicate that the object is now being controlled by a
+        mouse-drag or similar operation.
+
+        After calling this method, you should make calls to the drag() method
+        each time the mouse drags the position around, and always be sure to
+        finish with a call to endDrag() when the mouse is released, which allows
+        the position to continue moving freely according to the specified behaviour.
+    */
+    void beginDrag()
+    {
+        grabbedPos = position;
+        releaseVelocity = 0;
+        stopTimer();
+    }
+
+    /** Called during a mouse-drag operation, to indicate that the mouse has moved.
+        The delta is the difference between the position when beginDrag() was called
+        and the new position that's required.
+    */
+    void drag (double deltaFromStartOfDrag)
+    {
+        moveTo (grabbedPos + deltaFromStartOfDrag);
+    }
+
+    /** Called after beginDrag() and drag() to indicate that the drag operation has
+        now finished.
+    */
+    void endDrag()
+    {
+        startTimerHz (60);
+    }
+
+    /** Called outside of a drag operation to cause a nudge in the specified direction.
+        This is intended for use by e.g. mouse-wheel events.
+    */
+    void nudge (double deltaFromCurrentPosition)
+    {
+        startTimerHz (10);
+        moveTo (position + deltaFromCurrentPosition);
+    }
+
+    //==============================================================================
+    /** Returns the current position. */
+    double getPosition() const noexcept
+    {
+        return position;
+    }
+
+    /** Explicitly sets the position and stops any further movement.
+        This will cause a synchronous call to any listeners if the position actually
+        changes.
+    */
+    void setPosition (double newPosition)
+    {
+        stopTimer();
+        setPositionAndSendChange (newPosition);
+    }
+
+    //==============================================================================
+    /** Implement this class if you need to receive callbacks when the value of
+        an AnimatedPosition changes.
+        @see AnimatedPosition::addListener, AnimatedPosition::removeListener
+    */
+    class Listener
+    {
+    public:
+        virtual ~Listener() = default;
+
+        /** Called synchronously when an AnimatedPosition changes. */
+        virtual void positionChanged (AnimatedPosition&, double newPosition) = 0;
+    };
+
+    /** Adds a listener to be called when the value changes. */
+    void addListener (Listener* listener)       { listeners.add (listener); }
+
+    /** Removes a previously-registered listener. */
+    void removeListener (Listener* listener)    { listeners.remove (listener); }
+
+    //==============================================================================
+    /** The behaviour object.
+        This is public to let you tweak any parameters that it provides.
+    */
+    Behaviour behaviour;
+
+private:
+    //==============================================================================
+    double position = 0.0, grabbedPos = 0.0, releaseVelocity = 0.0;
+    Range<double> range;
+    Time lastUpdate, lastDrag;
+    ListenerList<Listener> listeners;
+
+    static double getSpeed (const Time last, double lastPos,
+                            const Time now, double newPos)
+    {
+        auto elapsedSecs = jmax (0.005, (now - last).inSeconds());
+        auto v = (newPos - lastPos) / elapsedSecs;
+        return std::abs (v) > 0.2 ? v : 0.0;
+    }
+
+    void moveTo (double newPos)
+    {
+        auto now = Time::getCurrentTime();
+        releaseVelocity = getSpeed (lastDrag, position, now, newPos);
+        behaviour.releasedWithVelocity (newPos, releaseVelocity);
+        lastDrag = now;
+
+        setPositionAndSendChange (newPos);
+    }
+
+    void setPositionAndSendChange (double newPosition)
+    {
+        newPosition = range.clipValue (newPosition);
+
+        if (position != newPosition)
+        {
+            position = newPosition;
+            listeners.call ([this, newPosition] (Listener& l) { l.positionChanged (*this, newPosition); });
+        }
+    }
+
+    void timerCallback() override
+    {
+        auto now = Time::getCurrentTime();
+        auto elapsed = jlimit (0.001, 0.020, (now - lastUpdate).inSeconds());
+        lastUpdate = now;
+        auto newPos = behaviour.getNextPosition (position, elapsed);
+
+        if (behaviour.isStopped (newPos))
+            stopTimer();
+        else
+            startTimerHz (60);
+
+        setPositionAndSendChange (newPos);
+    }
+
+    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (AnimatedPosition)
+};
+
+} // namespace juce