transposition.h

/*
  MusicXML Library
  Copyright (C) Grame 2006-2013
 
  This Source Code Form is subject to the terms of the Mozilla Public
  License, v. 2.0. If a copy of the MPL was not distributed with this
  file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
  Grame Research Laboratory, 11, cours de Verdun Gensoul 69002 Lyon - France
  research@grame.fr
*/
 
#ifndef __transposition__
#define __transposition__
 
#include <map>
#include <vector>
 
#include "exports.h"
#include "typedefs.h"
#include "transposevisitor.h"
#include "notevisitor.h"
 
 
namespace MusicXML2 
{
 
typedef int Chromatic;
typedef int Diatonic;
 
class EXP transposition : 
    public notevisitor,
    public visitor<S_cancel>,
    public visitor<S_fifths>,
    public visitor<S_encoding>,
    public visitor<S_part>
{
    protected:      
        Chromatic   fChromaticSteps;            // the target transposing interval
 
        std::vector<pair<std::string,int> > fFifthCycle;    // the fifth cycle table
 
        int     fTableShift;            // the current shift into the table of fifths
        int     fOctaveChange;          // the target octave change computed from fChromaticSteps
        int     fKeySign;               // the target key signature 
        int     fCurrentKeySign;        // the current key signature
 
        void    initialize  ();
 
        Sxmlelement buildSupport ( const string& elt, bool val) const;
 
        void    transpose ( string& pitch, float& alter, int& octave, int tableshift ) const;
        // set the note pitch according to the current shift into the table of fifths
        void    setPitch  ( notevisitor& v );
 
        ctree<xmlelement>::iterator insertAlter     ( S_note& elt, ctree<xmlelement>::iterator pos, float value );
        ctree<xmlelement>::iterator insertAccident  ( S_note& elt, ctree<xmlelement>::iterator pos, const string& value );
 
        virtual void visitStart ( S_part& elt );
        virtual void visitEnd( S_note& elt );
        // non standard keys are not yet supported
        virtual void visitStart ( S_cancel& elt );
        virtual void visitStart ( S_fifths& elt );
        virtual void visitEnd   ( S_encoding& elt );
        
    public:
                 transposition(int steps);
        virtual ~transposition();
 
 
        static int  getOctave ( Chromatic steps )           { return steps/12; }
 
        static Chromatic  getOctaveStep ( Chromatic steps ) { return steps%12; }
 
        static int  getKey ( Chromatic steps );
 
        static int getAccidental ( Diatonic pitch, int key );
 
        static string getAccident ( float alter );
 
        static int transposeKey ( int key, Chromatic steps, int& enharmonicChange );
};
 
} // namespace MusicXML2
 
 
#endif