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diff --git a/src/base/NotationRules.h b/src/base/NotationRules.h
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+// -*- c-basic-offset: 4 -*-
+
+
+/*
+    Rosegarden
+    A sequencer and musical notation editor.
+
+    This program is Copyright 2000-2008
+        Guillaume Laurent   <[email protected]>,
+        Chris Cannam        <[email protected]>,
+        Richard Bown        <[email protected]>
+
+    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 _NOTATION_RULES_H_
+#define _NOTATION_RULES_H_
+
+
+/**
+ * Common major and minor scales.
+ *
+ * For example, sixth note in 12-basis on Cmajor scale:
+ *   scale_Cmajor[5] = 9
+ */
+static int scale_Cmajor[] = { 0, 2, 4, 5, 7, 9, 11 };
+static int scale_Cminor[] = { 0, 2, 3, 5, 7, 8, 10 };
+static int scale_Cminor_harmonic[] = { 0, 2, 3, 5, 7, 8, 11 };
+/**
+ * Steps of common major and minor scales.
+ *
+ * For example, get accidental in 12-basis on Cmajor scale:
+ *   10 - scale_Cmajor[steps_Cmajor[10]] = 10 - 9 = +1
+ */
+static int steps_Cmajor[] = { 0, 0, 1, 1, 2, 3, 3, 4, 4, 5, 5, 6 };
+static int steps_Cminor[] = { 0, 0, 1, 2, 2, 3, 3, 4, 5, 5, 6, 6 };
+static int steps_Cminor_harmonic[] = { 0, 0, 1, 2, 2, 3, 3, 4, 5, 5, 5, 6 };
+/**
+ * Same as previosly, but the use of accidentals is explicitly written.
+ *
+ * For example, get accidental in 12-basis on Cmajor scale:
+ *   10 - scale_Cmajor[steps_Cmajor_with_sharps[10]] = 10 - 9 = +1
+ *   10 - scale_Cmajor[steps_Cmajor_with_flats[10]] = 10 - 11 = -1
+ */
+static int steps_Cmajor_with_sharps[] = { 0, 0, 1, 1, 2, 3, 3, 4, 4, 5, 5, 6 };
+static int steps_Cmajor_with_flats[] = { 0, 1, 1, 2, 2, 3, 4, 4, 5, 5, 6, 6 };
+
+namespace Rosegarden
+{
+
+/*
+ * NotationRules.h
+ *
+ * This file contains the model for rules which are used in notation decisions.
+ *
+ */
+
+class NotationRules
+{
+public:
+    NotationRules() { };
+    ~NotationRules() { };
+
+    /**
+     * If a single note is above the middle line, the preferred direction is up.
+     *
+     * If a single note is on the middle line, the preferred direction is down.
+     *
+     * If a single note is below the middle line, the preferred direction is down.
+     */
+    bool isStemUp(int heightOnStaff) { return heightOnStaff < 4; }
+
+    /**
+     * If the highest note in a chord is more distant from the middle
+     * line than the lowest note in a chord, the preferred direction is down.
+     *
+     * If the extreme notes in a chord are an equal distance from the 
+     * middle line, the preferred direction is down.
+     *
+     * If the lowest note in a chord is more distant from the middle
+     * line than the highest note in a chord, the preferred direction is up.
+     */
+    bool isStemUp(int highestHeightOnStaff, int lowestHeightOnStaff) {
+        return (highestHeightOnStaff + lowestHeightOnStaff) < 2*4;
+    }
+
+    /**
+     * If majority of notes are below the middle line, 
+     * the preferred direction is up.
+     *
+     * If notes are equally distributed around the middle line,
+     * the preferred direction is down.
+     *
+     * If majority of notes are above the middle line, 
+     * the preferred direction is down.
+     */
+    bool isBeamAboveWeighted(int weightAbove, int weightBelow) {
+        return weightBelow > weightAbove;
+    }
+
+    /**
+     * If the highest note in a group is more distant from the middle
+     * line than the lowest note in a group, the preferred direction is down.
+     *
+     * If the extreme notes in a group are an equal distance from the 
+     * middle line, the preferred direction is down.
+     *
+     * If the lowest note in a group is more distant from the middle
+     * line than the highest note in a group, the preferred direction is up.
+     */
+    bool isBeamAbove(int highestHeightOnStaff, int lowestHeightOnStaff) {
+        return (highestHeightOnStaff + lowestHeightOnStaff) < 2*4;
+    }
+    bool isBeamAbove(int highestHeightOnStaff, int lowestHeightOnStaff,
+                     int weightAbove, int weightBelow) {
+        if (highestHeightOnStaff + lowestHeightOnStaff == 2*4) {
+	    return isBeamAboveWeighted(weightAbove,weightBelow);
+	} else {
+	    return isBeamAbove(highestHeightOnStaff,lowestHeightOnStaff);
+	}
+    }
+};
+
+}
+
+#endif