1 files changed, 164 insertions, 0 deletions
diff --git a/src/base/ViewElement.h b/src/base/ViewElement.h
new file mode 100644
index 0000000..8cc3d09
--- /dev/null
+++ b/src/base/ViewElement.h
@@ -0,0 +1,164 @@
+// -*- c-basic-offset: 4 -*-
+
+
+/*
+    Rosegarden
+    A sequencer and musical notation editor.
+
+    This program is Copyright 2000-2008
+        Guillaume Laurent   <glaurent@telegraph-road.org>,
+        Chris Cannam        <cannam@all-day-breakfast.com>,
+        Richard Bown        <bownie@bownie.com>
+
+    The moral right of the authors to claim authorship of this work
+    has been asserted.
+
+    This program 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 2 of the
+    License, or (at your option) any later version.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#ifndef _VIEWELEMENT_H_
+#define _VIEWELEMENT_H_
+
+
+#include "Event.h"
+
+#include <set>
+#include <list>
+
+namespace Rosegarden 
+{
+
+/**
+ * The abstract base for classes which represent an Event as an
+ * on-screen graphic item (a note, a rectangle on a piano roll).
+ */
+
+class ViewElement
+{
+    friend class ViewElementList;
+    friend class Staff;
+
+public:
+    virtual ~ViewElement();
+
+    const Event* event() const { return m_event; }
+    Event*       event()       { return m_event; }
+
+    virtual timeT getViewAbsoluteTime() const  { return event()->getAbsoluteTime(); }
+    virtual timeT getViewDuration() const      { return event()->getDuration();     }
+
+    /**
+     * Returns the X coordinate of the element, as computed by the
+     * layout. This is not the coordinate of the associated canvas
+     * item.
+     *
+     * @see getCanvasX()
+     */
+    virtual double getLayoutX() const   { return m_layoutX; }
+
+    /**
+     * Returns the Y coordinate of the element, as computed by the
+     * layout. This is not the coordinate of the associated canvas
+     * item.
+     *
+     * @see getCanvasY()
+     */
+    virtual double getLayoutY() const   { return m_layoutY; }
+
+    /**
+     * Sets the X coordinate which was computed by the layout engine
+     * @see getLayoutX()
+     */
+    virtual void   setLayoutX(double x) { m_layoutX = x; }
+
+    /**
+     * Sets the Y coordinate which was computed by the layout engine
+     * @see getLayoutY()
+     */
+    virtual void   setLayoutY(double y) { m_layoutY = y; }
+
+    void dump(std::ostream&) const;
+
+    friend bool operator<(const ViewElement&, const ViewElement&);
+
+protected:
+    ViewElement(Event *);
+
+    double m_layoutX;
+    double m_layoutY;
+    
+    Event *m_event;
+};
+
+
+
+class ViewElementComparator
+{
+public:
+    bool operator()(const ViewElement *e1, const ViewElement *e2) const {
+        return *e1 < *e2;
+    }
+};
+
+/**
+ * This class owns the objects its items are pointing at.
+ *
+ * The template argument T must be a subclass of ViewElement.
+ */
+class ViewElementList : public std::multiset<ViewElement *, ViewElementComparator >
+{
+    typedef std::multiset<ViewElement *, ViewElementComparator > set_type;
+public:
+    typedef set_type::iterator iterator;
+
+    ViewElementList() : set_type() { }
+    virtual ~ViewElementList();
+
+    void insert(ViewElement *);
+    void erase(iterator i);
+    void erase(iterator from, iterator to);
+    void eraseSingle(ViewElement *);
+
+    iterator findPrevious(const std::string &type, iterator i);
+    iterator findNext(const std::string &type, iterator i);
+
+    /**
+     * Returns an iterator pointing to that specific element,
+     * end() otherwise
+     */
+    iterator findSingle(ViewElement *);
+
+    const_iterator findSingle(ViewElement *e) const {
+        return const_iterator(((const ViewElementList *)this)->findSingle(e));
+    }
+
+    /**
+     * Returns first iterator pointing at or after the given time,
+     * end() if time is beyond the end of the list
+     */ 
+    iterator findTime(timeT time);
+
+    const_iterator findTime(timeT time) const {
+        return const_iterator(((const ViewElementList *)this)->findTime(time));
+    }
+
+    /**
+     * Returns iterator pointing to the first element starting at
+     * or before the given absolute time
+     */
+    iterator findNearestTime(timeT time);
+
+    const_iterator findNearestTime(timeT time) const {
+        return const_iterator(((const ViewElementList *)this)->findNearestTime(time));
+    }
+};
+
+}
+
+
+#endif
+