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_opengl/geometry/juce_Draggable3DOrientation.h

@@ -0,0 +1,159 @@
+/*
+  ==============================================================================
+
+   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
+{
+
+//==============================================================================
+/**
+    Stores a 3D orientation, which can be rotated by dragging with the mouse.
+
+    @tags{OpenGL}
+*/
+class Draggable3DOrientation
+{
+public:
+    using VectorType      = Vector3D<float>;
+    using QuaternionType  = Quaternion<float>;
+
+    /** Creates a Draggable3DOrientation, initially set up to be aligned along the X axis. */
+    Draggable3DOrientation (float objectRadius = 0.5f) noexcept
+        : radius (jmax (0.1f, objectRadius)),
+          quaternion (VectorType::xAxis(), 0)
+    {
+    }
+
+    /** Creates a Draggable3DOrientation from a user-supplied quaternion. */
+    Draggable3DOrientation (const Quaternion<float>& quaternionToUse,
+                            float objectRadius = 0.5f) noexcept
+        : radius (jmax (0.1f, objectRadius)),
+          quaternion (quaternionToUse)
+    {
+    }
+
+    /** Resets the orientation, specifying the axis to align it along. */
+    void reset (const VectorType& axis) noexcept
+    {
+        quaternion = QuaternionType (axis, 0);
+    }
+
+    /** Sets the viewport area within which mouse-drag positions will occur.
+        You'll need to set this rectangle before calling mouseDown. The centre of the
+        rectangle is assumed to be the centre of the object that will be rotated, and
+        the size of the rectangle will be used to scale the object radius - see setRadius().
+    */
+    void setViewport (Rectangle<int> newArea) noexcept
+    {
+        area = newArea;
+    }
+
+    /** Sets the size of the rotated object, as a proportion of the viewport's size.
+        @see setViewport
+    */
+    void setRadius (float newRadius) noexcept
+    {
+        radius = jmax (0.1f, newRadius);
+    }
+
+    /** Begins a mouse-drag operation.
+        You must call this before any calls to mouseDrag(). The position that is supplied
+        will be treated as being relative to the centre of the rectangle passed to setViewport().
+    */
+    template <typename Type>
+    void mouseDown (Point<Type> mousePos) noexcept
+    {
+        lastMouse = mousePosToProportion (mousePos.toFloat());
+    }
+
+    /** Continues a mouse-drag operation.
+        After calling mouseDown() to begin a drag sequence, you can call this method
+        to continue it.
+    */
+    template <typename Type>
+    void mouseDrag (Point<Type> mousePos) noexcept
+    {
+        auto oldPos = projectOnSphere (lastMouse);
+        lastMouse = mousePosToProportion (mousePos.toFloat());
+        auto newPos = projectOnSphere (lastMouse);
+
+        quaternion *= rotationFromMove (oldPos, newPos);
+    }
+
+    /** Returns the matrix that should be used to apply the current orientation.
+        @see applyToOpenGLMatrix
+    */
+    Matrix3D<float> getRotationMatrix() const noexcept
+    {
+        return quaternion.getRotationMatrix();
+    }
+
+    /** Provides direct access to the quaternion. */
+    QuaternionType& getQuaternion() noexcept
+    {
+        return quaternion;
+    }
+
+private:
+    Rectangle<int> area;
+    float radius;
+    QuaternionType quaternion;
+    Point<float> lastMouse;
+
+    Point<float> mousePosToProportion (Point<float> mousePos) const noexcept
+    {
+        auto scale = jmin (area.getWidth(), area.getHeight()) / 2;
+
+        // You must call setViewport() to give this object a valid window size before
+        // calling any of the mouse input methods!
+        jassert (scale > 0);
+
+        return { (mousePos.x - (float) area.getCentreX()) / (float) scale,
+                 ((float) area.getCentreY() - mousePos.y) / (float) scale };
+    }
+
+    VectorType projectOnSphere (Point<float> pos) const noexcept
+    {
+        auto radiusSquared = radius * radius;
+        auto xySquared = pos.x * pos.x + pos.y * pos.y;
+
+        return { pos.x, pos.y,
+                 xySquared < radiusSquared * 0.5f ? std::sqrt (radiusSquared - xySquared)
+                                                  : (radiusSquared / (2.0f * std::sqrt (xySquared))) };
+    }
+
+    QuaternionType rotationFromMove (const VectorType& from, const VectorType& to) const noexcept
+    {
+        auto rotationAxis = (to ^ from);
+
+        if (rotationAxis.lengthIsBelowEpsilon())
+            rotationAxis = VectorType::xAxis();
+
+        auto d = jlimit (-1.0f, 1.0f, (from - to).length() / (2.0f * radius));
+
+        return QuaternionType::fromAngle (2.0f * std::asin (d), rotationAxis);
+    }
+};
+
+} // namespace juce