fix macOS build (following Projucer changes made in Windows, which removed /Applications/JUCE/modules from its headers). move JUCE headers under source control, so that Windows and macOS can both build against same version of JUCE. remove AUv3 target (I think it's an iOS thing, so it will never work with this macOS fluidsynth dylib).

modules/juce_gui_basics/layout/juce_AnimatedPositionBehaviours.h

@@ -0,0 +1,161 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library.
+   Copyright (c) 2017 - ROLI Ltd.
+
+   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 5 End-User License
+   Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
+   27th April 2017).
+
+   End User License Agreement: www.juce.com/juce-5-licence
+   Privacy Policy: www.juce.com/juce-5-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
+{
+
+//==============================================================================
+/** Contains classes for different types of physics behaviours - these classes
+    are used as template parameters for the AnimatedPosition class.
+*/
+namespace AnimatedPositionBehaviours
+{
+    /** A non-snapping behaviour that allows the content to be freely flicked in
+        either direction, with momentum based on the velocity at which it was
+        released, and variable friction to make it come to a halt.
+
+        This class is intended to be used as a template parameter to the
+        AnimatedPosition class.
+
+        @see AnimatedPosition
+
+        @tags{GUI}
+    */
+    struct ContinuousWithMomentum
+    {
+        ContinuousWithMomentum() noexcept
+        {
+        }
+
+        /** Sets the friction that damps the movement of the value.
+            A typical value is 0.08; higher values indicate more friction.
+        */
+        void setFriction (double newFriction) noexcept
+        {
+            damping = 1.0 - newFriction;
+        }
+
+        /** Sets the minimum velocity of the movement. Any velocity that's slower than
+            this will stop the animation. The default is 0.05. */
+        void setMinimumVelocity (double newMinimumVelocityToUse) noexcept
+        {
+            minimumVelocity = newMinimumVelocityToUse;
+        }
+
+        /** Called by the AnimatedPosition class. This tells us the position and
+            velocity at which the user is about to release the object.
+            The velocity is measured in units/second.
+        */
+        void releasedWithVelocity (double /*position*/, double releaseVelocity) noexcept
+        {
+            velocity = releaseVelocity;
+        }
+
+        /** Called by the AnimatedPosition class to get the new position, after
+            the given time has elapsed.
+        */
+        double getNextPosition (double oldPos, double elapsedSeconds) noexcept
+        {
+            velocity *= damping;
+
+            if (std::abs (velocity) < minimumVelocity)
+                velocity = 0;
+
+            return oldPos + velocity * elapsedSeconds;
+        }
+
+        /** Called by the AnimatedPosition class to check whether the object
+            is now stationary.
+        */
+        bool isStopped (double /*position*/) const noexcept
+        {
+            return velocity == 0.0;
+        }
+
+    private:
+        double velocity = 0, damping = 0.92, minimumVelocity = 0.05;
+    };
+
+    //==============================================================================
+    /** A behaviour that gravitates an AnimatedPosition object towards the nearest
+        integer position when released.
+
+        This class is intended to be used as a template parameter to the
+        AnimatedPosition class. It's handy when using an AnimatedPosition to show a
+        series of pages, because it allows the pages can be scrolled smoothly, but when
+        released, snaps back to show a whole page.
+
+        @see AnimatedPosition
+
+        @tags{GUI}
+    */
+    struct SnapToPageBoundaries
+    {
+        SnapToPageBoundaries() noexcept   : targetSnapPosition()
+        {
+        }
+
+        /** Called by the AnimatedPosition class. This tells us the position and
+            velocity at which the user is about to release the object.
+            The velocity is measured in units/second.
+        */
+        void releasedWithVelocity (double position, double releaseVelocity) noexcept
+        {
+            targetSnapPosition = std::floor (position + 0.5);
+
+            if (releaseVelocity >  1.0 && targetSnapPosition < position)  ++targetSnapPosition;
+            if (releaseVelocity < -1.0 && targetSnapPosition > position)  --targetSnapPosition;
+        }
+
+        /** Called by the AnimatedPosition class to get the new position, after
+            the given time has elapsed.
+        */
+        double getNextPosition (double oldPos, double elapsedSeconds) const noexcept
+        {
+            if (isStopped (oldPos))
+                return targetSnapPosition;
+
+            const double snapSpeed = 10.0;
+            const double velocity = (targetSnapPosition - oldPos) * snapSpeed;
+            const double newPos = oldPos + velocity * elapsedSeconds;
+
+            return isStopped (newPos) ? targetSnapPosition : newPos;
+        }
+
+        /** Called by the AnimatedPosition class to check whether the object
+            is now stationary.
+        */
+        bool isStopped (double position) const noexcept
+        {
+            return std::abs (targetSnapPosition - position) < 0.001;
+        }
+
+    private:
+        double targetSnapPosition;
+    };
+}
+
+} // namespace juce