PianoRollEditor.cpp

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/*
 * Hydrogen
 * Copyright(c) 2002-2008 by Alex >Comix< Cominu [comix@users.sourceforge.net]
 * Copyright(c) 2008-2025 The hydrogen development team [hydrogen-devel@lists.sourceforge.net]
 *
 * http://www.hydrogen-music.org
 *
 * 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.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see https://www.gnu.org/licenses
 *
 */
 
#include "PianoRollEditor.h"
#include "PatternEditorPanel.h"
#include "PatternEditorRuler.h"
#include "PatternEditorInstrumentList.h"
#include "UndoActions.h"
#include <cassert>
 
#include <core/Hydrogen.h>
#include <core/Basics/Instrument.h>
#include <core/Basics/InstrumentList.h>
#include <core/Basics/Note.h>
#include <core/Basics/Pattern.h>
#include <core/Basics/PatternList.h>
#include <core/AudioEngine/AudioEngine.h>
#include <core/Helpers/Xml.h>
using namespace H2Core;
 
#include "../Compatibility/MouseEvent.h"
#include "../HydrogenApp.h"
#include "../Skin.h"
 
 
PianoRollEditor::PianoRollEditor( QWidget *pParent, PatternEditorPanel *panel,
                                                                  QScrollArea *pScrollView)
        : PatternEditor( pParent, panel )
        , m_pScrollView( pScrollView )
{
        m_editor = PatternEditor::Editor::PianoRoll;
        
        m_nGridHeight = 10;
        m_nOctaves = 7;
 
        setAttribute(Qt::WA_OpaquePaintEvent);
 
        m_nEditorHeight = m_nOctaves * 12 * m_nGridHeight;
 
        m_pTemp = new QPixmap( m_nEditorWidth, m_nEditorHeight );
 
        m_nCursorPitch = 0;
 
        resize( m_nEditorWidth, m_nEditorHeight );
        
        createBackground();
 
        HydrogenApp::get_instance()->addEventListener( this );
 
        m_bNeedsUpdate = true;
        m_bNeedsBackgroundUpdate = true;
        m_bSelectNewNotes = false;
}
 
 
 
PianoRollEditor::~PianoRollEditor()
{
        INFOLOG( "DESTROY" );
        delete m_pTemp;
}
 
 
void PianoRollEditor::updateEditor( bool bPatternOnly )
{
        // Ensure that m_pPattern is up to date.
        updatePatternInfo();
        updateWidth();
        
        if ( !bPatternOnly ) {
                m_bNeedsBackgroundUpdate = true;
        }
        if ( !m_bNeedsUpdate ) {
                m_bNeedsUpdate = true;
                update();
        }
}
 
void PianoRollEditor::finishUpdateEditor()
{
        assert( m_bNeedsUpdate );
        resize( m_nEditorWidth, height() );
 
        // Ensure that m_pPattern is up to date.
        updatePatternInfo();
 
        if ( m_bNeedsBackgroundUpdate ) {
                createBackground();
        } else {
                drawPattern();
        }
        
        //      ERRORLOG(QString("update editor %1").arg(m_nEditorWidth));
        m_bNeedsUpdate = false;
        m_bNeedsBackgroundUpdate = false;
}
 
void PianoRollEditor::selectedInstrumentChangedEvent()
{
        // Update pattern only
        updateEditor( true );
}
 
void PianoRollEditor::selectedPatternChangedEvent()
{
        updateEditor();
}
 
void PianoRollEditor::songModeActivationEvent() {
        updateEditor();
}
 
void PianoRollEditor::paintEvent(QPaintEvent *ev)
{
        if (!isVisible()) {
                return;
        }
        
        auto pPref = Preferences::get_instance();
        
        qreal pixelRatio = devicePixelRatio();
        if ( pixelRatio != m_pBackgroundPixmap->devicePixelRatio() || m_bBackgroundInvalid ) {
                createBackground();
        }
 
        QPainter painter( this );
        if ( m_bNeedsUpdate ) {
                finishUpdateEditor();
        }
        painter.drawPixmap( ev->rect(), *m_pTemp,
                                                QRectF( pixelRatio * ev->rect().x(),
                                                                pixelRatio * ev->rect().y(),
                                                                pixelRatio * ev->rect().width(),
                                                                pixelRatio * ev->rect().height() ) );
 
        // Draw playhead
        if ( m_nTick != -1 ) {
 
                int nOffset = Skin::getPlayheadShaftOffset();
                int nX = static_cast<int>(static_cast<float>(PatternEditor::nMargin) +
                                                                  static_cast<float>(m_nTick) *
                                                                  m_fGridWidth );
                Skin::setPlayheadPen( &painter, false );
                painter.drawLine( nX, 2, nX, height() - 2 );
        }
 
        drawFocus( painter );
        
        m_selection.paintSelection( &painter );
 
        // Draw cursor
        if ( hasFocus() && !HydrogenApp::get_instance()->hideKeyboardCursor() ) {
                QPoint pos = cursorPosition();
 
                QPen pen( pPref->getColorTheme()->m_cursorColor );
                pen.setWidth( 2 );
                painter.setPen( pen );
                painter.setBrush( Qt::NoBrush );
                painter.setRenderHint( QPainter::Antialiasing );
                painter.drawRoundedRect( getKeyboardCursorRect(), 4, 4 );
        }
}
 
void PianoRollEditor::drawFocus( QPainter& painter ) {
 
        auto pPref = H2Core::Preferences::get_instance();
        
        if ( ! m_bEntered && ! hasFocus() ) {
                return;
        }
        
        QColor color = pPref->getColorTheme()->m_highlightColor;
 
        // If the mouse is placed on the widget but the user hasn't
        // clicked it yet, the highlight will be done more transparent to
        // indicate that keyboard inputs are not accepted yet.
        if ( ! hasFocus() ) {
                color.setAlpha( 125 );
        }
 
        int nStartY = HydrogenApp::get_instance()->getPatternEditorPanel()->getPianoRollEditorScrollArea()->verticalScrollBar()->value();
        int nStartX = HydrogenApp::get_instance()->getPatternEditorPanel()->getPianoRollEditorScrollArea()->horizontalScrollBar()->value();
        int nEndY = nStartY + HydrogenApp::get_instance()->getPatternEditorPanel()->getPianoRollEditorScrollArea()->viewport()->size().height();
        int nEndX = std::min( nStartX + HydrogenApp::get_instance()->getPatternEditorPanel()->getPianoRollEditorScrollArea()->viewport()->size().width(), width() );
 
        QPen pen( color );
        pen.setWidth( 4 );
        painter.setPen( pen );
        painter.drawLine( QPoint( nStartX, nStartY ), QPoint( nEndX, nStartY ) );
        painter.drawLine( QPoint( nStartX, nStartY ), QPoint( nStartX, nEndY ) );
        painter.drawLine( QPoint( nEndX, nStartY ), QPoint( nEndX, nEndY ) );
        painter.drawLine( QPoint( nEndX, nEndY ), QPoint( nStartX, nEndY ) );
}
 
void PianoRollEditor::createBackground()
{
        auto pPref = H2Core::Preferences::get_instance();
        
        const QColor backgroundColor = pPref->getColorTheme()->m_patternEditor_backgroundColor;
        const QColor backgroundInactiveColor = pPref->getColorTheme()->m_windowColor;
        const QColor alternateRowColor = pPref->getColorTheme()->m_patternEditor_alternateRowColor;
        const QColor octaveColor = pPref->getColorTheme()->m_patternEditor_octaveRowColor;
        // The line corresponding to the default pitch set to new notes
        // will be highlighted.
        const QColor baseNoteColor = octaveColor.lighter( 119 );
        const QColor lineColor( pPref->getColorTheme()->m_patternEditor_lineColor );
        const QColor lineInactiveColor( pPref->getColorTheme()->m_windowTextColor.darker( 170 ) );
 
        unsigned start_x = 0;
        unsigned end_x = m_nActiveWidth;
 
        // Resize pixmap if pixel ratio has changed
        qreal pixelRatio = devicePixelRatio();
        if ( m_pBackgroundPixmap->width() != m_nEditorWidth ||
                 m_pBackgroundPixmap->height() != m_nEditorHeight ||
                 m_pBackgroundPixmap->devicePixelRatio() != pixelRatio ) {
                delete m_pBackgroundPixmap;
                m_pBackgroundPixmap = new QPixmap( width()  * pixelRatio , height() * pixelRatio );
                m_pBackgroundPixmap->setDevicePixelRatio( pixelRatio );
                delete m_pTemp;
                m_pTemp = new QPixmap( width()  * pixelRatio , height() * pixelRatio );
                m_pTemp->setDevicePixelRatio( pixelRatio );
        }
 
        m_pBackgroundPixmap->fill( backgroundInactiveColor );
 
        QPainter p( m_pBackgroundPixmap );
 
        for ( uint ooctave = 0; ooctave < m_nOctaves; ++ooctave ) {
                unsigned start_y = ooctave * 12 * m_nGridHeight;
 
                for ( int ii = 0; ii < 12; ++ii ) {
                        if ( ii == 0 || ii == 2 || ii == 4 || ii == 6 || ii == 7 ||
                                 ii == 9 || ii == 11 ) {
                                if ( ooctave % 2 != 0 ) {
                                        p.fillRect( start_x, start_y + ii * m_nGridHeight,
                                                                end_x - start_x, start_y + ( ii + 1 ) * m_nGridHeight,
                                                                octaveColor );
                                } else {
                                        p.fillRect( start_x, start_y + ii * m_nGridHeight,
                                                                end_x - start_x, start_y + ( ii + 1 ) * m_nGridHeight,
                                                                backgroundColor );
                                }
                        } else {
                                p.fillRect( start_x, start_y + ii * m_nGridHeight,
                                                        end_x - start_x, start_y + ( ii + 1 ) * m_nGridHeight,
                                                        alternateRowColor );
                        }
                }
 
                // Highlight base note pitch
                if ( ooctave == 3 ) {
                        p.fillRect( start_x, start_y + 11 * m_nGridHeight,
                                                end_x - start_x, start_y + 12 * m_nGridHeight,
                                                baseNoteColor );
                }
        }
 
 
        // horiz lines
        p.setPen( lineColor );
        for ( uint row = 0; row < ( 12 * m_nOctaves ); ++row ) {
                unsigned y = row * m_nGridHeight;
                p.drawLine( start_x, y, end_x, y );
        }
 
        if ( m_nActiveWidth + 1 < m_nEditorWidth ) {
                p.setPen( lineInactiveColor );
                for ( uint row = 0; row < ( 12 * m_nOctaves ); ++row ) {
                        unsigned y = row * m_nGridHeight;
                        p.drawLine( m_nActiveWidth, y, m_nEditorWidth, y );
                }
        }
 
        //draw text
        QFont font( pPref->getApplicationFontFamily(), getPointSize( pPref->getFontSize() ) );
        p.setFont( font );
        p.setPen( pPref->getColorTheme()->m_patternEditor_textColor );
 
        int offset = 0;
        int insertx = 3;
        for ( int oct = 0; oct < (int)m_nOctaves; oct++ ){
                if( oct > 3 ){
                        p.drawText( insertx, m_nGridHeight  + offset, "B" );
                        p.drawText( insertx, 10 + m_nGridHeight  + offset, "A#" );
                        p.drawText( insertx, 20 + m_nGridHeight  + offset, "A" );
                        p.drawText( insertx, 30 + m_nGridHeight  + offset, "G#" );
                        p.drawText( insertx, 40 + m_nGridHeight  + offset, "G" );
                        p.drawText( insertx, 50 + m_nGridHeight  + offset, "F#" );
                        p.drawText( insertx, 60 + m_nGridHeight  + offset, "F" );
                        p.drawText( insertx, 70 + m_nGridHeight  + offset, "E" );
                        p.drawText( insertx, 80 + m_nGridHeight  + offset, "D#" );
                        p.drawText( insertx, 90 + m_nGridHeight  + offset, "D" );
                        p.drawText( insertx, 100 + m_nGridHeight  + offset, "C#" );
                        p.drawText( insertx, 110 + m_nGridHeight  + offset, "C" );
                        offset += 12 * m_nGridHeight;
                }else
                {
                        p.drawText( insertx, m_nGridHeight  + offset, "b" );
                        p.drawText( insertx, 10 + m_nGridHeight  + offset, "a#" );
                        p.drawText( insertx, 20 + m_nGridHeight  + offset, "a" );
                        p.drawText( insertx, 30 + m_nGridHeight  + offset, "g#" );
                        p.drawText( insertx, 40 + m_nGridHeight  + offset, "g" );
                        p.drawText( insertx, 50 + m_nGridHeight  + offset, "f#" );
                        p.drawText( insertx, 60 + m_nGridHeight  + offset, "f" );
                        p.drawText( insertx, 70 + m_nGridHeight  + offset, "e" );
                        p.drawText( insertx, 80 + m_nGridHeight  + offset, "d#" );
                        p.drawText( insertx, 90 + m_nGridHeight  + offset, "d" );
                        p.drawText( insertx, 100 + m_nGridHeight  + offset, "c#" );
                        p.drawText( insertx, 110 + m_nGridHeight  + offset, "c" );
                        offset += 12 * m_nGridHeight;
                }
        }
 
        drawGridLines( p, Qt::DashLine );
        drawPattern();
        
        p.setPen( QPen( lineColor, 2, Qt::SolidLine ) );
        p.drawLine( m_nEditorWidth, 0, m_nEditorWidth, m_nEditorHeight );
 
        m_bBackgroundInvalid = false;
}
 
 
void PianoRollEditor::drawPattern()
{
        //INFOLOG( "draw pattern" );
 
        validateSelection();
 
        qreal pixelRatio = devicePixelRatio();
        
        QPainter p( m_pTemp );
        // copy the background image
        p.drawPixmap( rect(), *m_pBackgroundPixmap,
                                                QRectF( pixelRatio * rect().x(),
                                                                pixelRatio * rect().y(),
                                                                pixelRatio * rect().width(),
                                                                pixelRatio * rect().height() ) );
 
        // for each note...
        for ( Pattern *pPattern : getPatternsToShow() ) {
                bool bIsForeground = ( pPattern == m_pPattern );
                const Pattern::notes_t* notes = pPattern->get_notes();
                FOREACH_NOTE_CST_IT_BEGIN_LENGTH( notes, it, pPattern ) {
                        Note *note = it->second;
                        assert( note );
                        drawNote( note, &p, bIsForeground );
                }
        }
 
}
 
 
void PianoRollEditor::drawNote( Note *pNote, QPainter *pPainter, bool bIsForeground )
{
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        if ( pNote->get_instrument() == pHydrogen->getSelectedInstrument() ) {
                QPoint pos ( PatternEditor::nMargin + pNote->get_position() * m_fGridWidth,
                                         m_nGridHeight * pitchToLine( pNote->get_notekey_pitch() ) + 1);
                drawNoteSymbol( *pPainter, pos, pNote, bIsForeground );
        }
}
 
 
void PianoRollEditor::addOrRemoveNote( int nColumn, int nRealColumn, int nLine,
                                                                           int nNotekey, int nOctave,
                                                                           bool bDoAdd, bool bDoDelete )
{
        if ( m_pPattern == nullptr || m_nSelectedPatternNumber == -1 ) {
                // No pattern selected.
                return;
        }
        
        Note::Octave octave = (Note::Octave)nOctave;
        Note::Key notekey = (Note::Key)nNotekey;
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        int nSelectedInstrumentnumber = pHydrogen->getSelectedInstrumentNumber();
        auto pSelectedInstrument = pHydrogen->getSelectedInstrument();
        if ( pSelectedInstrument == nullptr ) {
                DEBUGLOG( "No instrument selected" );
                return;
        }
 
        Note* pOldNote = m_pPattern->find_note( nColumn, nRealColumn, pSelectedInstrument,
                                                                                          notekey, octave );
 
        int nLength = -1;
        float fVelocity = 0.8f;
        float fPan = 0.0f;
        float fLeadLag = 0.0f;
        float fProbability = 1.0f;
 
        if ( pOldNote && !bDoDelete ) {
                // Found an old note, but we don't want to delete, so just return.
                return;
        } else if ( !pOldNote && !bDoAdd ) {
                // No note there, but we don't want to add a new one, so return.
                return;
        }
 
        if ( pOldNote ) {
                nLength = pOldNote->get_length();
                fVelocity = pOldNote->get_velocity();
                fPan = pOldNote->getPan();
                fLeadLag = pOldNote->get_lead_lag();
                notekey = pOldNote->get_key();
                octave = pOldNote->get_octave();
                fProbability = pOldNote->get_probability();
        }
 
        if ( pOldNote == nullptr ) {
                // hear note
                Preferences *pref = Preferences::get_instance();
                if ( pref->getHearNewNotes() && pSelectedInstrument->hasSamples() ) {
                        Note *pNote2 = new Note( pSelectedInstrument );
                        pNote2->set_key_octave( notekey, octave );
                        m_pAudioEngine->getSampler()->noteOn( pNote2 );
                }
        }
 
        SE_addOrDeleteNotePianoRollAction *action = new SE_addOrDeleteNotePianoRollAction( nColumn,
                                                                                                                                                                           nLine,
                                                                                                                                                                           m_nSelectedPatternNumber,
                                                                                                                                                                           nSelectedInstrumentnumber,
                                                                                                                                                                           nLength,
                                                                                                                                                                           fVelocity,
                                                                                                                                                                           fPan,
                                                                                                                                                                           fLeadLag,
                                                                                                                                                                           notekey,
                                                                                                                                                                           octave,
                                                                                                                                                                           fProbability,
                                                                                                                                                                           pOldNote != nullptr );
        HydrogenApp::get_instance()->m_pUndoStack->push( action );
 
}
 
 
void PianoRollEditor::mouseClickEvent( QMouseEvent *ev ) {
 
        if ( m_pPattern == nullptr || m_nSelectedPatternNumber == -1 ) {
                return;
        }
 
        auto pEv = static_cast<MouseEvent*>( ev );
 
        auto pHydrogenApp = HydrogenApp::get_instance();
        std::shared_ptr<Song> pSong = Hydrogen::get_instance()->getSong();
 
        int nPressedLine = ((int) pEv->position().y()) / ((int) m_nGridHeight);
        if ( nPressedLine >= (int) m_nOctaves * 12 ) {
                return;
        }
 
        int nColumn = getColumn( pEv->position().x(), /* bUseFineGrained=*/ true );
 
        if ( nColumn >= (int)m_pPattern->get_length() ) {
                update( 0, 0, width(), height() );
                return;
        }
        m_pPatternEditorPanel->setCursorPosition( nColumn );
 
        auto pSelectedInstrument = Hydrogen::get_instance()->getSelectedInstrument();
        int nSelectedInstrumentnumber = Hydrogen::get_instance()->getSelectedInstrumentNumber();
        
        if ( pSelectedInstrument == nullptr ) {
                ERRORLOG( "No instrument selected" );
                return;
        }
 
        int nPitch = lineToPitch( nPressedLine );
        Note::Octave pressedoctave = Note::pitchToOctave( nPitch );
        Note::Key pressednotekey = Note::pitchToKey( nPitch );
        m_nCursorPitch = nPitch;
 
        if (ev->button() == Qt::LeftButton ) {
 
                unsigned nRealColumn = 0;
                if( pEv->position().x() > PatternEditor::nMargin ) {
                        nRealColumn = (pEv->position().x() - PatternEditor::nMargin) / static_cast<float>(m_fGridWidth);
                }
 
                if ( ev->modifiers() & Qt::ShiftModifier ) {
                        H2Core::Note *pNote = m_pPattern->find_note( nColumn, nRealColumn, pSelectedInstrument, pressednotekey, pressedoctave );
                        if ( pNote != nullptr ) {
                                SE_addOrDeleteNotePianoRollAction *action = new SE_addOrDeleteNotePianoRollAction( nColumn,
                                                                                                                                                                                                   nPressedLine,
                                                                                                                                                                                                   m_nSelectedPatternNumber,
                                                                                                                                                                                                   nSelectedInstrumentnumber,
                                                                                                                                                                                                   pNote->get_length(),
                                                                                                                                                                                                   pNote->get_velocity(),
                                                                                                                                                                                                   pNote->getPan(),
                                                                                                                                                                                                   pNote->get_lead_lag(),
                                                                                                                                                                                                   pNote->get_key(),
                                                                                                                                                                                                   pNote->get_octave(),
                                                                                                                                                                                                   pNote->get_probability(),
                                                                                                                                                                                                   pNote != nullptr );
                                pHydrogenApp->m_pUndoStack->push( action );
                        } else {
                                SE_addPianoRollNoteOffAction *action = new SE_addPianoRollNoteOffAction( nColumn, nPressedLine, m_nSelectedPatternNumber, nSelectedInstrumentnumber );
                                pHydrogenApp->m_pUndoStack->push( action );
                        }
                        return;
                }
 
                addOrRemoveNote( nColumn, nRealColumn, nPressedLine, pressednotekey, pressedoctave );
 
        } else if ( ev->button() == Qt::RightButton ) {
                // Show context menu
                m_pPopupMenu->popup( pEv->globalPosition().toPoint() );
 
        }
 
}
 
void PianoRollEditor::mousePressEvent( QMouseEvent* ev ) {
        auto pEv = static_cast<MouseEvent*>( ev );
 
        if ( pEv->position().x() > m_nActiveWidth ) {
                return;
        }
 
        PatternEditor::mousePressEvent( ev );
        
        auto pHydrogenApp = HydrogenApp::get_instance();
 
        // Hide cursor in case this behavior was selected in the
        // Preferences.
        bool bOldCursorHidden = pHydrogenApp->hideKeyboardCursor();
        pHydrogenApp->setHideKeyboardCursor( true );
 
        // Cursor just got hidden.
        if ( bOldCursorHidden != pHydrogenApp->hideKeyboardCursor() ) {
                // Immediate update to prevent visual delay.
                m_pPatternEditorPanel->getPatternEditorRuler()->update();
                update();
        }
 
        // Update cursor position
        if ( ! pHydrogenApp->hideKeyboardCursor() ) {
                int nPressedLine = ((int) pEv->position().y()) / ((int) m_nGridHeight);
                if ( nPressedLine >= (int) m_nOctaves * 12 ) {
                        return;
                }
                m_nCursorPitch = lineToPitch( nPressedLine );  
 
                int nColumn = getColumn( pEv->position().x(), /* bUseFineGrained=*/ true );
                if ( ( m_pPattern != nullptr &&
                           nColumn >= (int)m_pPattern->get_length() ) ||
                         nColumn >= MAX_INSTRUMENTS ) {
                        return;
                }
 
                m_pPatternEditorPanel->setCursorPosition( nColumn );
        
                update();
                m_pPatternEditorPanel->getPatternEditorRuler()->update();
        }
}
 
void PianoRollEditor::mouseDragStartEvent( QMouseEvent *ev )
{
        if ( m_pPattern == nullptr ) {
                return;
        }
 
        auto pEv = static_cast<MouseEvent*>( ev );
 
        // Handles cursor repositioning and hiding and stores general
        // properties.
        PatternEditor::mouseDragStartEvent( ev );
        
        m_pDraggedNote = nullptr;
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        int nColumn = getColumn( pEv->position().x() );
        auto pSelectedInstrument = pHydrogen->getSelectedInstrument();
        if ( pSelectedInstrument == nullptr ) {
                DEBUGLOG( "No instrument selected" );
                return;
        }
 
        int nRow = std::floor(static_cast<float>(pEv->position().y()) /
                                                  static_cast<float>(m_nGridHeight));
 
        Note::Octave pressedOctave = Note::pitchToOctave( lineToPitch( nRow ) );
        Note::Key pressedNoteKey = Note::pitchToKey( lineToPitch( nRow ) );
        m_nCursorPitch = lineToPitch( nRow );
 
        if (ev->button() == Qt::RightButton ) {
 
                int nRealColumn = 0;
                if( pEv->position().x() > PatternEditor::nMargin ) {
                        nRealColumn =
                                static_cast<int>(std::floor(
                                        static_cast<float>((pEv->position().x() - PatternEditor::nMargin)) /
                                        m_fGridWidth));
                }
 
                m_pDraggedNote = m_pPattern->find_note( nColumn, nRealColumn,
                                                                                                pSelectedInstrument,
                                                                                                pressedNoteKey,
                                                                                                pressedOctave, false );
 
                // Store note-specific properties.
                storeNoteProperties( m_pDraggedNote );
                
                m_nRow = nRow;
        }
}
 
void PianoRollEditor::mouseDragUpdateEvent( QMouseEvent *ev )
{
        auto pEv = static_cast<MouseEvent*>( ev );
 
        int nRow = std::floor(static_cast<float>(pEv->position().y()) /
                                                  static_cast<float>(m_nGridHeight));
        if ( nRow >= (int) m_nOctaves * 12 ) {
                return;
        }
 
        PatternEditor::mouseDragUpdateEvent( ev );
}
 
void PianoRollEditor::addOrDeleteNoteAction( int nColumn,
                                                                                         int pressedLine,
                                                                                         int selectedPatternNumber,
                                                                                         int selectedinstrument,
                                                                                         int oldLength,
                                                                                         float oldVelocity,
                                                                                         float fOldPan,
                                                                                         float oldLeadLag,
                                                                                         int oldNoteKeyVal,
                                                                                         int oldOctaveKeyVal,
                                                                                         float fProbability,
                                                                                         bool noteOff,
                                                                                         bool isDelete )
{
        if ( m_pPattern == nullptr ) {
                return;
        }
        
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        std::shared_ptr<Song> pSong = pHydrogen->getSong();
        PatternList *pPatternList = pHydrogen->getSong()->getPatternList();
 
        auto pSelectedInstrument = pSong->getInstrumentList()->get( selectedinstrument );
        if ( pSelectedInstrument == nullptr ) {
                ERRORLOG( QString( "Instrument [%1] could not be found" )
                                  .arg( selectedinstrument ) );
                return;
        }
 
        Pattern *pPattern = nullptr;
        if ( ( selectedPatternNumber != -1 ) && ( (uint)selectedPatternNumber < pPatternList->size() ) ) {
                pPattern = pPatternList->get( selectedPatternNumber );
        }
 
        Note::Octave pressedoctave = Note::pitchToOctave( lineToPitch( pressedLine ) );
        Note::Key pressednotekey = Note::pitchToKey( lineToPitch( pressedLine ) );
 
        m_pAudioEngine->lock( RIGHT_HERE );     // lock the audio engine
 
        if ( isDelete ) {
                Note* note = m_pPattern->find_note( nColumn, -1, pSelectedInstrument, pressednotekey, pressedoctave );
                if ( note ) {
                        // the note exists...remove it!
                        m_pPattern->remove_note( note );
                        delete note;
                } else {
                        ERRORLOG( "Could not find note to delete" );
                }
        } else {
                // create the new note
                unsigned nPosition = nColumn;
                float fVelocity = oldVelocity;
                float fPan = fOldPan;
                int nLength = oldLength;
 
                if ( noteOff ) {
                        fVelocity = 0.0f;
                        fPan = 0.f;
                        nLength = 1;
                }
                
                if ( pPattern != nullptr ) {
                        Note *pNote = new Note( pSelectedInstrument, nPosition, fVelocity, fPan, nLength );
                        pNote->set_note_off( noteOff );
                        if( ! noteOff ) {
                                pNote->set_lead_lag( oldLeadLag );
                        }
                        pNote->set_key_octave( pressednotekey, pressedoctave );
                        pNote->set_probability( fProbability );
                        pPattern->insert_note( pNote );
                        if ( m_bSelectNewNotes ) {
                                m_selection.addToSelection( pNote );
                        }
                }
        }
        pHydrogen->setIsModified( true );
        m_pAudioEngine->unlock(); // unlock the audio engine
 
        m_pPatternEditorPanel->updateEditors( true );
}
 
 
// Find a note that matches pNote, and move it from (nColumn, nRow) to (nNewColumn, nNewRow)
void PianoRollEditor::moveNoteAction( int nColumn,
                                                                          Note::Octave octave,
                                                                          Note::Key key,
                                                                          int nPattern,
                                                                          int nNewColumn,
                                                                          Note::Octave newOctave,
                                                                          Note::Key newKey,
                                                                          Note *pNote)
{
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        std::shared_ptr<Song> pSong = pHydrogen->getSong();
 
        m_pAudioEngine->lock( RIGHT_HERE );
        PatternList *pPatternList = pSong->getPatternList();
        Note *pFoundNote = nullptr;
 
        if ( nPattern < 0 || nPattern > pPatternList->size() ) {
                ERRORLOG( "Invalid pattern number" );
                m_pAudioEngine->unlock();
                return;
        }
 
        Pattern *pPattern = pPatternList->get( nPattern );
 
        FOREACH_NOTE_IT_BOUND_END((Pattern::notes_t *)pPattern->get_notes(), it, nColumn) {
                Note *pCandidateNote = it->second;
                if ( pCandidateNote->get_instrument() == pNote->get_instrument()
                         && pCandidateNote->get_octave() == octave
                         && pCandidateNote->get_key() == key
                         && pCandidateNote->get_velocity() == pNote->get_velocity()
                         && pCandidateNote->get_lead_lag() == pNote->get_lead_lag()
                         && pCandidateNote->getPan() == pNote->getPan()
                         && pCandidateNote->get_note_off() == pNote->get_note_off() ) {
                        pFoundNote = pCandidateNote;
                        if ( m_selection.isSelected( pFoundNote ) ) {
                                // If a candidate note is in the selection, this will be the one to move.
                                break;
                        }
                }
        }
        if ( pFoundNote == nullptr ) {
                ERRORLOG( "Couldn't find note to move" );
                m_pAudioEngine->unlock();
                return;
        }
 
        // Remove and insert at new position
        pPattern->remove_note( pFoundNote );
        pFoundNote->set_position( nNewColumn );
        pPattern->insert_note( pFoundNote );
        pFoundNote->set_key_octave( newKey, newOctave );
 
        pHydrogen->setIsModified( true );
        m_pAudioEngine->unlock();
 
        m_pPatternEditorPanel->updateEditors( true );
}
 
 
QPoint PianoRollEditor::cursorPosition()
{
        uint x = PatternEditor::nMargin + m_pPatternEditorPanel->getCursorPosition() * m_fGridWidth;
        uint y = m_nGridHeight * pitchToLine( m_nCursorPitch ) + 1;
        return QPoint(x, y);
}
 
void PianoRollEditor::selectAll()
{
        selectInstrumentNotes( Hydrogen::get_instance()->getSelectedInstrumentNumber() );
}
 
 
void PianoRollEditor::deleteSelection()
{
        if ( m_nSelectedPatternNumber == -1 ) {
                // No pattern selected.
                return;
        }
 
        if ( m_selection.begin() != m_selection.end() ) {
                // Delete a selection.
                Hydrogen *pHydrogen = Hydrogen::get_instance();
                int nSelectedInstrumentNumber = pHydrogen->getSelectedInstrumentNumber();
                auto pSelectedInstrument = pHydrogen->getSelectedInstrument();
                if ( pSelectedInstrument == nullptr ) {
                        DEBUGLOG( "No instrument selected" );
                        return;
                }
                QUndoStack *pUndo = HydrogenApp::get_instance()->m_pUndoStack;
                validateSelection();
                std::list< QUndoCommand * > actions;
                for ( Note *pNote : m_selection ) {
                        if ( m_selection.isSelected( pNote ) ) {
                                if ( pNote->get_instrument() == pSelectedInstrument ) {
                                        int nLine = pitchToLine( pNote->get_notekey_pitch() );
                                        actions.push_back( new SE_addOrDeleteNotePianoRollAction( pNote->get_position(),
                                                                                                                                                          nLine,
                                                                                                                                                          m_nSelectedPatternNumber,
                                                                                                                                                          nSelectedInstrumentNumber,
                                                                                                                                                          pNote->get_length(),
                                                                                                                                                          pNote->get_velocity(),
                                                                                                                                                          pNote->getPan(),
                                                                                                                                                          pNote->get_lead_lag(),
                                                                                                                                                          pNote->get_key(),
                                                                                                                                                          pNote->get_octave(),
                                                                                                                                                          pNote->get_probability(),
                                                                                                                                                          true ) );
                                }
                        }
                }
                m_selection.clearSelection();
 
                pUndo->beginMacro("delete notes");
                for ( QUndoCommand * pAction : actions ) {
                        pUndo->push( pAction );
                }
                pUndo->endMacro();
        }
}
 

void PianoRollEditor::paste()
{
        if ( m_pPattern == nullptr || m_nSelectedPatternNumber == -1 ) {
                // No pattern selected.
                return;
        }
 
        QClipboard *clipboard = QApplication::clipboard();
        QUndoStack *pUndo = HydrogenApp::get_instance()->m_pUndoStack;
        auto pInstrList = Hydrogen::get_instance()->getSong()->getInstrumentList();
        int nInstrument = Hydrogen::get_instance()->getSelectedInstrumentNumber();
        XMLNode noteList;
        int nDeltaPos = 0, nDeltaPitch = 0;
 
 
        XMLDoc doc;
        if ( ! doc.setContent( clipboard->text() ) ) {
                // Pasted something that's not valid XML.
                return;
        }
 
        XMLNode selection = doc.firstChildElement( "noteSelection" );
        if ( ! selection.isNull() ) {
 
                // Got a noteSelection.
                // <noteSelection>
                //   <noteList>
                //     <note> ...
                noteList = selection.firstChildElement( "noteList" );
                if ( noteList.isNull() ) {
                        return;
                }
 
                XMLNode positionNode = selection.firstChildElement( "sourcePosition" );
 
                // If position information is supplied in the selection, use
                // it to adjust the location relative to the current keyboard
                // input cursor.
                if ( !positionNode.isNull() ) {
                        int nCurrentPos = m_pPatternEditorPanel->getCursorPosition();
 
                        nDeltaPos = nCurrentPos -
                                positionNode.read_int( "minColumn", nCurrentPos );
                        nDeltaPitch = m_nCursorPitch -
                                positionNode.read_int( "maxPitch", m_nCursorPitch );
                }
        } else {
 
                XMLNode instrumentLine = doc.firstChildElement( "instrument_line" );
                if ( ! instrumentLine.isNull() ) {
                        // Found 'instrument_line', structure is:
                        // <instrument_line>
                        //   <patternList>
                        //     <pattern>
                        //       <noteList>
                        //         <note> ...
                        XMLNode patternList = instrumentLine.firstChildElement( "patternList" );
                        if ( patternList.isNull() ) {
                                return;
                        }
                        XMLNode pattern = patternList.firstChildElement( "pattern" );
                        if ( pattern.isNull() ) {
                                return;
                        }
                        // Don't attempt to paste multiple patterns
                        if ( ! pattern.nextSiblingElement( "pattern" ).isNull() ) {
                                QMessageBox::information( this, "Hydrogen", tr( "Cannot paste multi-pattern selection" ) );
                                return;
                        }
                        noteList = pattern.firstChildElement( "noteList" );
                        if ( noteList.isNull() ) {
                                return;
                        }
                }
        }
 
        m_selection.clearSelection();
        m_bSelectNewNotes = true;
 
        if ( noteList.hasChildNodes() ) {
 
                pUndo->beginMacro( "paste notes" );
                for ( XMLNode n = noteList.firstChildElement( "note" ); ! n.isNull(); n = n.nextSiblingElement() ) {
                        Note *pNote = Note::load_from( &n, pInstrList );
                        int nPos = pNote->get_position() + nDeltaPos;
                        int nPitch = pNote->get_notekey_pitch() + nDeltaPitch;
 
                        if ( nPos >= 0 && nPos < m_pPattern->get_length() && nPitch >= 12 * OCTAVE_MIN && nPitch < 12 * (OCTAVE_MAX+1) ) {
                                int nLine = pitchToLine( nPitch );
                                pUndo->push( new SE_addOrDeleteNotePianoRollAction( nPos,
                                                                                                                                        nLine,
                                                                                                                                        m_nSelectedPatternNumber,
                                                                                                                                        nInstrument,
                                                                                                                                        pNote->get_length(),
                                                                                                                                        pNote->get_velocity(),
                                                                                                                                        pNote->getPan(),
                                                                                                                                        pNote->get_lead_lag(),
                                                                                                                                        0,
                                                                                                                                        0,
                                                                                                                                        pNote->get_probability(),
                                                                                                                                        false ) );
                        }
                        delete pNote;
                }
                pUndo->endMacro();
        }
 
        m_bSelectNewNotes = false;
}
 
 
void PianoRollEditor::keyPressEvent( QKeyEvent * ev )
{
        if ( m_pPattern == nullptr ) {
                return;
        }
 
        auto pHydrogenApp = HydrogenApp::get_instance();
        bool bOldCursorHidden = pHydrogenApp->hideKeyboardCursor();
                
        const int nBlockSize = 5, nWordSize = 5;
        bool bIsSelectionKey = m_selection.keyPressEvent( ev );
        bool bUnhideCursor = true;
        updateModifiers( ev );
 
        if ( bIsSelectionKey ) {
                // Selection key, nothing more to do (other than update editor)
        } else if ( ev->matches( QKeySequence::MoveToNextChar ) || ev->matches( QKeySequence::SelectNextChar ) ) {
                // ->
                m_pPatternEditorPanel->moveCursorRight();
 
        } else if ( ev->matches( QKeySequence::MoveToNextWord ) || ev->matches( QKeySequence::SelectNextWord ) ) {
                // ->
                m_pPatternEditorPanel->moveCursorRight( nWordSize );
 
        } else if ( ev->matches( QKeySequence::MoveToEndOfLine ) || ev->matches( QKeySequence::SelectEndOfLine ) ) {
                // -->|
                m_pPatternEditorPanel->setCursorPosition( m_pPattern->get_length() );
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousChar ) || ev->matches( QKeySequence::SelectPreviousChar ) ) {
                // <-
                m_pPatternEditorPanel->moveCursorLeft();
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousWord ) || ev->matches( QKeySequence::SelectPreviousWord ) ) {
                // <-
                m_pPatternEditorPanel->moveCursorLeft( nWordSize );
 
        } else if ( ev->matches( QKeySequence::MoveToStartOfLine ) || ev->matches( QKeySequence::SelectStartOfLine ) ) {
                // |<--
                m_pPatternEditorPanel->setCursorPosition( 0 );
 
        } else if ( ev->matches( QKeySequence::MoveToNextLine ) || ev->matches( QKeySequence::SelectNextLine ) ) {
                if ( m_nCursorPitch > Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MIN, (Note::Key)KEY_MIN ) ) {
                        m_nCursorPitch --;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToEndOfBlock ) || ev->matches( QKeySequence::SelectEndOfBlock ) ) {
                m_nCursorPitch = std::max( Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MIN, (Note::Key)KEY_MIN ),
                                                                   m_nCursorPitch - nBlockSize );
 
        } else if ( ev->matches( QKeySequence::MoveToNextPage ) || ev->matches( QKeySequence::SelectNextPage ) ) {
                // Page down -- move down by a whole octave
                int nMinPitch = Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MIN, (Note::Key)KEY_MIN );
                m_nCursorPitch -= 12;
                if ( m_nCursorPitch < nMinPitch ) {
                        m_nCursorPitch = nMinPitch;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToEndOfDocument ) || ev->matches( QKeySequence::SelectEndOfDocument ) ) {
                m_nCursorPitch = Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MIN, (Note::Key)KEY_MIN );
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousLine ) || ev->matches( QKeySequence::SelectPreviousLine ) ) {
                if ( m_nCursorPitch < Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MAX, (Note::Key)KEY_MAX ) ) {
                        m_nCursorPitch ++;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToStartOfBlock ) || ev->matches( QKeySequence::SelectStartOfBlock ) ) {
                m_nCursorPitch = std::min( Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MAX, (Note::Key)KEY_MAX ),
                                                                   m_nCursorPitch + nBlockSize );
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousPage ) || ev->matches( QKeySequence::SelectPreviousPage ) ) {
                int nMaxPitch = Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MAX, (Note::Key)KEY_MAX );
                m_nCursorPitch += 12;
                if ( m_nCursorPitch >= nMaxPitch ) {
                        m_nCursorPitch = nMaxPitch;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToStartOfDocument ) || ev->matches( QKeySequence::SelectStartOfDocument ) ) {
                m_nCursorPitch = Note::octaveKeyToPitch( (Note::Octave)OCTAVE_MAX, (Note::Key)KEY_MAX );
 
        } else if ( ev->key() == Qt::Key_Enter || ev->key() == Qt::Key_Return ) {
                // Key: Enter/Return : Place or remove note at current position
                int pressedline = pitchToLine( m_nCursorPitch );
                int nPitch = lineToPitch( pressedline );
                addOrRemoveNote( m_pPatternEditorPanel->getCursorPosition(), -1, pressedline,
                                                 Note::pitchToKey( nPitch ), Note::pitchToOctave( nPitch ) );
 
        } else if ( ev->matches( QKeySequence::SelectAll ) ) {
                // Key: Ctrl + A: Select all
                bUnhideCursor = false;
                selectAll();
 
        } else if ( ev->matches( QKeySequence::Deselect ) ) {
                // Key: Shift + Ctrl + A: clear selection
                bUnhideCursor = false;
                selectNone();
 
        } else if ( ev->key() == Qt::Key_Delete ) {
                // Key: Delete: delete selection or note at keyboard cursor
                bUnhideCursor = false;
                if ( m_selection.begin() != m_selection.end() ) {
                        deleteSelection();
                } else {
                        // Delete a note under the keyboard cursor
                        int pressedline = pitchToLine( m_nCursorPitch );
                        int nPitch = lineToPitch( pressedline );
                        addOrRemoveNote( m_pPatternEditorPanel->getCursorPosition(), -1, pressedline,
                                                         Note::pitchToKey( nPitch ), Note::pitchToOctave( nPitch ),
                                                         /*bDoAdd=*/false, /*bDoDelete=*/true );
                }
 
        } else if ( ev->matches( QKeySequence::Copy ) ) {
                bUnhideCursor = false;
                copy();
 
        } else if ( ev->matches( QKeySequence::Paste ) ) {
                bUnhideCursor = false;
                paste();
 
        } else if ( ev->matches( QKeySequence::Cut ) ) {
                bUnhideCursor = false;
                cut();
 
        } else {
                ev->ignore();
                pHydrogenApp->setHideKeyboardCursor( true );
                
                if ( bOldCursorHidden != pHydrogenApp->hideKeyboardCursor() ) {
                        m_pPatternEditorPanel->getPatternEditorRuler()->update();
                        update();
                }
                return;
        }
 
        // Update editor
        QPoint pos = cursorPosition();
        if ( bUnhideCursor ) {
                HydrogenApp::get_instance()->setHideKeyboardCursor( false );
        }
        m_pScrollView->ensureVisible( pos.x(), pos.y() );
        m_selection.updateKeyboardCursorPosition( getKeyboardCursorRect() );
 
        if ( ! HydrogenApp::get_instance()->hideKeyboardCursor() ) {
                // Immediate update to prevent visual delay.
                m_pPatternEditorPanel->getPatternEditorRuler()->update();
        }
        
        updateEditor( true );
        ev->accept();
}
 
// Selection manager interface
void PianoRollEditor::selectionMoveEndEvent( QInputEvent *ev )
{
        updateModifiers( ev );
 
        QPoint offset = movingGridOffset();
        if ( offset.x() == 0 && offset.y() == 0 ) {
                // Move with no effect.
                return;
        }
 
        validateSelection();
 
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        int nSelectedPatternNumber = pHydrogen->getSelectedPatternNumber();
        int nSelectedInstrumentNumber = pHydrogen->getSelectedInstrumentNumber();
 
        if ( m_pPattern == nullptr || nSelectedPatternNumber == -1 ) {
                // No pattern selected. Nothing to be selected.
                return;
        }
 
        QUndoStack *pUndo = HydrogenApp::get_instance()->m_pUndoStack;
 
        if (m_bCopyNotMove) {
                pUndo->beginMacro( "copy notes" );
        } else {
                pUndo->beginMacro( "move notes" );
        }
        std::list< Note * > selectedNotes;
        for ( auto pNote : m_selection ) {
                selectedNotes.push_back( pNote );
        }
 
        if ( m_bCopyNotMove ) {
                // Clear selection so the new notes can be selection instead
                // of the originals.
                m_selection.clearSelection();
        }
        m_bSelectNewNotes = true;
 
        for ( auto pNote : selectedNotes ) {
                int nPosition = pNote->get_position();
                int nNewPosition = nPosition + offset.x();
 
                Note::Octave octave = pNote->get_octave();
                Note::Key key = pNote->get_key();
                // Transpose note
                int nNewPitch = pNote->get_notekey_pitch() - offset.y();
                int nLine = pitchToLine( nNewPitch );
                Note::Octave newOctave = Note::pitchToOctave( nNewPitch );
                Note::Key newKey = Note::pitchToKey( nNewPitch );
                bool bNoteInRange = ( newOctave >= OCTAVE_MIN && newOctave <= OCTAVE_MAX && nNewPosition >= 0
                                                          && nNewPosition < m_pPattern->get_length() );
 
                if ( m_bCopyNotMove ) {
                        if ( bNoteInRange ) {
                                pUndo->push( new SE_addOrDeleteNotePianoRollAction( nNewPosition,
                                                                                                                                        nLine,
                                                                                                                                        nSelectedPatternNumber,
                                                                                                                                        nSelectedInstrumentNumber,
                                                                                                                                        pNote->get_length(),
                                                                                                                                        pNote->get_velocity(),
                                                                                                                                        pNote->getPan(),
                                                                                                                                        pNote->get_lead_lag(),
                                                                                                                                        newKey,
                                                                                                                                        newOctave,
                                                                                                                                        pNote->get_probability(),
                                                                                                                                        false ) );
                        }
                } else {
                        if ( bNoteInRange ) {
                                pUndo->push( new SE_moveNotePianoRollAction( nPosition, octave, key, nSelectedPatternNumber, nNewPosition, newOctave, newKey, pNote ) );
                        } else {
                                pUndo->push( new SE_addOrDeleteNotePianoRollAction( pNote->get_position(),
                                                                                                                                        nLine - offset.y(),
                                                                                                                                        nSelectedPatternNumber,
                                                                                                                                        nSelectedInstrumentNumber,
                                                                                                                                        pNote->get_length(),
                                                                                                                                        pNote->get_velocity(),
                                                                                                                                        pNote->getPan(),
                                                                                                                                        pNote->get_lead_lag(),
                                                                                                                                        key,
                                                                                                                                        octave,
                                                                                                                                        pNote->get_probability(),
                                                                                                                                        true ) );
                        }
                }
        }
 
        m_bSelectNewNotes = false;
        pUndo->endMacro();
}
 
std::vector<PianoRollEditor::SelectionIndex> PianoRollEditor::elementsIntersecting( QRect r ) 
{
        std::vector<SelectionIndex> result;
        if ( m_pPattern == nullptr ) {
                return std::move( result );
        }
        
        int w = 8;
        int h = m_nGridHeight - 2;
        auto pSelectedInstrument = Hydrogen::get_instance()->getSelectedInstrument();
        if ( pSelectedInstrument == nullptr ) {
                DEBUGLOG( "No instrument selected" );
                return std::move( result );
        }
 
        r = r.normalized();
        if ( r.top() == r.bottom() && r.left() == r.right() ) {
                r += QMargins( 2, 2, 2, 2 );
        }
 
        // Calculate the first and last position values that this rect will intersect with
        int x_min = (r.left() - w - PatternEditor::nMargin) / m_fGridWidth;
        int x_max = (r.right() + w - PatternEditor::nMargin) / m_fGridWidth;
 
        const Pattern::notes_t* pNotes = m_pPattern->get_notes();
 
        for ( auto it = pNotes->lower_bound( x_min ); it != pNotes->end() && it->first <= x_max; ++it ) {
                Note *pNote = it->second;
                if ( pNote->get_instrument() == pSelectedInstrument ) {
                        uint start_x = PatternEditor::nMargin + pNote->get_position() * m_fGridWidth;
                        uint start_y = m_nGridHeight * pitchToLine( pNote->get_notekey_pitch() ) + 1;
 
                        if ( r.intersects( QRect( start_x -4 , start_y, w, h ) ) ) {
                                result.push_back( pNote );
                        }
                }
        }
        updateEditor( true );
        return std::move( result );
}

QRect PianoRollEditor::getKeyboardCursorRect()
{
        const QPoint pos = cursorPosition();
        float fHalfWidth;
        if ( m_nResolution != MAX_NOTES ) {
                // Corresponds to the distance between grid lines on 1/64 resolution.
                fHalfWidth = m_fGridWidth * 3;
        } else {
                // Corresponds to the distance between grid lines set to resolution
                // "off".
                fHalfWidth = m_fGridWidth;
        }
        return QRect( pos.x() - fHalfWidth, pos.y()-2,
                                  fHalfWidth * 2, m_nGridHeight+3 );
}
 
void PianoRollEditor::onPreferencesChanged( H2Core::Preferences::Changes changes )
{
        if ( changes & ( H2Core::Preferences::Changes::Colors |
                                         H2Core::Preferences::Changes::Font ) ) {
                invalidateBackground();
                update();
        }
}