#4849 RiuViewer: Add support for a comparison gridbox

Add support for controlling the Comparison view window
Use overlay rendering for overlay items
Add a removeColorLegend method
Update overlay positioning on each redraw

ApplicationCode/UserInterface/RiuComparisonViewMover.h

@@ -0,0 +1,58 @@
+/////////////////////////////////////////////////////////////////////////////////
+//
+//  Copyright (C) 2018-     Equinor ASA
+//
+//  ResInsight is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  ResInsight is distributed in the hope that it will be useful, but WITHOUT ANY
+//  WARRANTY; without even the implied warranty of MERCHANTABILITY or
+//  FITNESS FOR A PARTICULAR PURPOSE.
+//
+//  See the GNU General Public License at <http://www.gnu.org/licenses/gpl.html>
+//  for more details.
+//
+/////////////////////////////////////////////////////////////////////////////////
+#pragma once
+
+#include "cvfBase.h"
+#include "cvfObject.h"
+
+#include <QPointer>
+
+#include <QMouseEvent>
+#include <QPainter>
+
+namespace caf
+{
+class Viewer;
+}
+
+class RiuComparisonViewMover : public QObject
+{
+public:
+    RiuComparisonViewMover( caf::Viewer* viewer );
+
+    virtual bool eventFilter( QObject* watched, QEvent* event ) override;
+
+    void paintMoverHandles( QPainter* painter );
+
+private:
+    enum DragState
+    {
+        NONE,
+        COMPLETE_BOX,
+        LEFT_EDGE,
+        RIGHT_EDGE,
+        TOP_EDGE,
+        BOTTOM_EDGE,
+    };
+
+    DragState findHandleUnderMouse( const QPoint& mousePos );
+
+    QPointer<caf::Viewer> m_viewer;
+    DragState             m_dragState;
+    DragState             m_highlightHandle;
+};