MuseScore/libmscore/chordline.cpp

//=============================================================================
//  MuseScore
//  Music Composition & Notation
//
//  Copyright (C) 2010-2012 Werner Schweer
//
//  This program is free software; you can redistribute it and/or modify
//  it under the terms of the GNU General Public License version 2
//  as published by the Free Software Foundation and appearing in
//  the file LICENCE.GPL
//=============================================================================

#include "chordline.h"
#include "xml.h"
#include "chord.h"
#include "measure.h"
#include "system.h"
#include "note.h"

namespace Ms {

//---------------------------------------------------------
//   ChordLine
//---------------------------------------------------------

ChordLine::ChordLine(Score* s)
   : Element(s)
      {
      setFlags(ElementFlag::MOVABLE | ElementFlag::SELECTABLE);
      modified = false;
      _chordLineType = ChordLineType::NOTYPE;
      _straight = false;
      _lengthX = 0.0;
      _lengthY = 0.0;
      }

ChordLine::ChordLine(const ChordLine& cl)
   : Element(cl)
      {
      path     = cl.path;
      modified = cl.modified;
      _chordLineType = cl._chordLineType;
      _straight = cl._straight;
      _lengthX = cl._lengthX;
      _lengthY = cl._lengthY;
      }

//---------------------------------------------------------
//   setChordLineType
//---------------------------------------------------------

void ChordLine::setChordLineType(ChordLineType st)
      {
      qreal x2 = 0;
      qreal y2 = 0;
      switch(st) {
            case ChordLineType::NOTYPE:
                  break;
            case ChordLineType::FALL:
                  x2 = 2;
                  y2 = 2;
                  break;
            case ChordLineType::PLOP:
                  x2 = -2;
                  y2 = -2;
                  break;
            case ChordLineType::SCOOP:
                  x2 = -2;
                  y2 = 2;
                  break;
            default:
            case ChordLineType::DOIT:
                  x2 = 2;
                  y2 = -2;
                  break;
            }
      if (st != ChordLineType::NOTYPE) {
            path = QPainterPath();
            // chordlines to the right of the note
            if (st == ChordLineType::FALL || st == ChordLineType::DOIT)
                  path.cubicTo(x2/2, 0.0, x2, y2/2, x2, y2);
            // chordlines to the left of the note
            if (st == ChordLineType::PLOP || st == ChordLineType::SCOOP)
                  path.cubicTo(0.0, y2/2, x2/2, y2, x2, y2);
            }
      _chordLineType = st;
      }

//---------------------------------------------------------
//   layout
//---------------------------------------------------------

void ChordLine::layout()
      {
      qreal _spatium = spatium();
      if (parent()) {
            Note* note = chord()->upNote();
            QPointF p(note->pos());
            // chordlines to the right of the note
            if (_chordLineType == ChordLineType::FALL || _chordLineType == ChordLineType::DOIT)
                  setPos(p.x() + note->headWidth() + _spatium * .2, p.y());
            // chordlines to the left of the note
            if (_chordLineType == ChordLineType::PLOP)
                  setPos(p.x() + note->headWidth() * .25, p.y() - note->headHeight() * .75);
            if (_chordLineType == ChordLineType::SCOOP) {
                  qreal x = p.x() + (chord()->up() ? note->headWidth() * .25 : _spatium * -.2);
                  setPos(x, p.y() + note->headHeight() * .75);
                  }
            }
      else
            setPos(0.0, 0.0);
      QRectF r(path.boundingRect());
      int x1, y1, width, height = 0;

      /* layout of sides have been fine-tuned below to get the
         bounding box fitting around the slide, factoring in spatium,
         length of slide, height, and offset from note, plus some
         extra space for user mis-click error. These values have been
         set to match Guitar Pro behaviour. */

      // negative gradient after note
      if (_straight && _chordLineType == ChordLineType::FALL) {
            x1 = r.x() + _spatium;
            y1 = r.height() + _spatium * 0.8 + _lengthY * 0.95;
            width =  r.width() + _spatium * 2 + _lengthX;
            height = -r.height() - _spatium * 2 - _lengthY * 0.95;
            }
      // positive gradient after note
      else if (_straight && _chordLineType ==  ChordLineType::DOIT) {
            x1 = r.x() + _spatium;
            y1 = r.y() + _spatium * 0.5 - _lengthY * 0.15;
            width =  r.width() + _spatium * 2.2 + _lengthX * 0.95;
            height = -r.height() - _spatium * 2 + _lengthY * 0.95;
            }
      // negative gradient before note
      else if (_straight && _chordLineType == ChordLineType::SCOOP) {
            x1 = -r.x() - _spatium * 1.3;
            y1 = -r.y() / 4 - _spatium * 0.5;
            width =  -r.width() - _spatium * 2.5 + _lengthX;
            height = r.height() - _spatium * 1.9  + _lengthY * 1.1;
            }
      // positive gradient before note
      else if (_straight && _chordLineType == ChordLineType::PLOP) {
            x1 = -r.x() - _spatium * 1.2;
            y1 = -r.y() + _spatium * 1.5 + _lengthY;
            width =  -r.width() - _spatium * 2.9 + _lengthX * 1.15;
            height = -r.height() - _spatium * 2.5 - _lengthY * 0.93;
            }
      else  {
            x1 = r.x() * _spatium;
            y1 = r.y() * _spatium;
            width = r.width() * _spatium;
            height = r.height() * _spatium;
            }
      bbox().setRect(x1, y1, width, height);
      }

//---------------------------------------------------------
//   read
//---------------------------------------------------------

void ChordLine::read(XmlReader& e)
      {
      path = QPainterPath();
      while (e.readNextStartElement()) {
            const QStringRef& tag(e.name());
            if (tag == "Path") {
                  path = QPainterPath();
                  QPointF curveTo;
                  QPointF p1;
                  int state = 0;
                  while (e.readNextStartElement()) {
                        const QStringRef& tag(e.name());
                        if (tag == "Element") {
                              int type = e.intAttribute("type");
                              qreal x  = e.doubleAttribute("x");
                              qreal y  = e.doubleAttribute("y");
                              switch(QPainterPath::ElementType(type)) {
                                    case QPainterPath::MoveToElement:
                                          path.moveTo(x, y);
                                          break;
                                    case QPainterPath::LineToElement:
                                          path.lineTo(x, y);
                                          break;
                                    case QPainterPath::CurveToElement:
                                          curveTo.rx() = x;
                                          curveTo.ry() = y;
                                          state = 1;
                                          break;
                                    case QPainterPath::CurveToDataElement:
                                          if (state == 1) {
                                                p1.rx() = x;
                                                p1.ry() = y;
                                                state = 2;
                                                }
                                          else if (state == 2) {
                                                path.cubicTo(curveTo, p1, QPointF(x, y));
                                                state = 0;
                                                }
                                          break;
                                    }
                              e.skipCurrentElement(); //needed to go to next Element in Path
                              }
                        else
                              e.unknown();
                        }
                  modified = true;
                  }
            else if (tag == "subtype")
                  setChordLineType(ChordLineType(e.readInt()));
             else if (tag == "straight")
                  setStraight(e.readInt());
             else if (tag == "lengthX")
                  setLengthX(e.readInt());
             else if (tag == "lengthY")
                  setLengthY(e.readInt());

            else if (!Element::readProperties(e))
                  e.unknown();
            }
      }

//---------------------------------------------------------
//   write
//---------------------------------------------------------

void ChordLine::write(Xml& xml) const
      {
      xml.stag(name());
      xml.tag("subtype", int(_chordLineType));
      xml.tag("straight", _straight, false);
      xml.tag("lengthX", _lengthX, 0.0);
      xml.tag("lengthY", _lengthY, 0.0);
      Element::writeProperties(xml);
      if (modified) {
            int n = path.elementCount();
            xml.stag("Path");
            for (int i = 0; i < n; ++i) {
                  const QPainterPath::Element& e = path.elementAt(i);
                  xml.tagE(QString("Element type=\"%1\" x=\"%2\" y=\"%3\"")
                     .arg(int(e.type)).arg(e.x).arg(e.y));
                  }
            xml.etag();
            }
      xml.etag();
      }

//---------------------------------------------------------
//   Symbol::draw
//---------------------------------------------------------

void ChordLine::draw(QPainter* painter) const
      {
      qreal _spatium = spatium();

      if (this->isStraight()) {
            painter->save();
            QPen pen(curColor());
            pen.setWidthF(_spatium * .15);
            pen.setCapStyle(Qt::RoundCap);
            painter->setPen(pen);

            /* we use constants below in order to shift the drawing of
               straight lines away from the notehead. This will gave
               almost identical results to the Guitar Pro
               represenation. */

            // negative gradient after note
            if (_chordLineType == ChordLineType::FALL)
                  painter->drawLine(QLineF(_spatium + 3.0, -_spatium + 2.0, _spatium * 3 + _lengthX, 2.0 + _spatium / 2 + _lengthY));
            // positive gradient, after note
            else if (_chordLineType == ChordLineType::DOIT)
                  painter->drawLine(QLineF(_spatium + 3.0, _spatium / 3 - 2.0, _spatium * 3 + _lengthX, -2.0 - _spatium / 2 + _lengthY));
            else if (_chordLineType == ChordLineType::SCOOP)
                  painter->drawLine(QLineF(-3.5 * _spatium + _lengthX, -_spatium * 2 + _lengthY, -_spatium - 2.0, -_spatium / 2));
            else if (_chordLineType == ChordLineType::PLOP)
                  painter->drawLine(QLineF(-3.5 * _spatium + _lengthX, _spatium + 3.0 + _lengthY, -_spatium - 3.0, -_spatium / 5));

            painter->restore();
            }
      else  {
            painter->scale(_spatium, _spatium);
            painter->setPen(QPen(curColor(), .15, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin));
            painter->setBrush(Qt::NoBrush);
            painter->drawPath(path);
            painter->scale(1.0/_spatium, 1.0/_spatium);
            }
      }

//---------------------------------------------------------
//   editDrag
//---------------------------------------------------------

void ChordLine::editDrag(const EditData& ed)
      {
      int n = path.elementCount();
      QPainterPath p;
      qreal sp = spatium();
      _lengthX += ed.delta.x();
      _lengthY += ed.delta.y();

      // used to limit how grips can affect the slide, stops the user from being able to turn one kind of slide into another
      int slideBoundary = 5;
      if ((_chordLineType == ChordLineType::PLOP || _chordLineType == ChordLineType::FALL) && _lengthY < -slideBoundary)
            _lengthY = -slideBoundary;
      else if ((_chordLineType == ChordLineType::FALL || _chordLineType == ChordLineType::DOIT) && _lengthX < -slideBoundary)
            _lengthX = -slideBoundary;
      else if ((_chordLineType == ChordLineType::DOIT || _chordLineType == ChordLineType::SCOOP) && _lengthY > slideBoundary)
            _lengthY = slideBoundary;
      else if ((_chordLineType == ChordLineType::SCOOP || _chordLineType == ChordLineType::PLOP)  && _lengthX > slideBoundary)
            _lengthX = slideBoundary;

      qreal dx = ed.delta.x() / sp;
      qreal dy = ed.delta.y() / sp;
      for (int i = 0; i < n; ++i) {
            const QPainterPath::Element& e = path.elementAt(i);
            qreal x = e.x;
            qreal y = e.y;
            if (ed.curGrip == i) {
                  x += dx;
                  y += dy;
                  }
            switch(e.type) {
                  case QPainterPath::CurveToDataElement:
                        break;
                  case QPainterPath::MoveToElement:
                        p.moveTo(x, y);
                        break;
                  case QPainterPath::LineToElement:
                        p.lineTo(x, y);
                        break;
                  case QPainterPath::CurveToElement:
                        {
                        qreal x2 = path.elementAt(i+1).x;
                        qreal y2 = path.elementAt(i+1).y;
                        qreal x3 = path.elementAt(i+2).x;
                        qreal y3 = path.elementAt(i+2).y;
                        if (i + 1 == ed.curGrip) {
                              x2 += dx;
                              y2 += dy;
                              }
                        else if (i + 2 == ed.curGrip) {
                              x3 += dx;
                              y3 += dy;
                              }
                        p.cubicTo(x, y, x2, y2, x3, y3);
                        i += 2;
                        }
                        break;
                  }
            }
      path = p;
      modified = true;
      }

//---------------------------------------------------------
//   updateGrips
//---------------------------------------------------------

void ChordLine::updateGrips(int* grips, int* defaultGrip, QRectF* grip) const
      {
      int n = path.elementCount();
      QPointF cp(pagePos());
      qreal sp = spatium();
      if (_straight) {
            // calculate grip to be near the head of the slide rather than near the notehead
            int xOffsetAfterNote = sp * 3 + 2;
            int xOffsetBeforeNote = sp * 3 + 4;
            int yOffsetAterNote = -sp;
            int yOffsetBeforeNote = sp + 4;
            if (_chordLineType == ChordLineType::DOIT)
                  grip[0].translate(QPointF(xOffsetAfterNote, yOffsetAterNote));
            else if (_chordLineType == ChordLineType::FALL)
                  grip[0].translate(QPointF(xOffsetAfterNote, -yOffsetAterNote));
            else if (_chordLineType == ChordLineType::SCOOP)
                  grip[0].translate(QPointF(-xOffsetBeforeNote, -yOffsetBeforeNote));
            else if (_chordLineType == ChordLineType::PLOP)
                  grip[0].translate(QPointF(-xOffsetBeforeNote, yOffsetBeforeNote));

            // limit the number of grips to one
            *grips = 1;
            // translate on the length and height - stops the grips from goint past boundries of slide
            grip[0].translate(cp + QPointF(_lengthX, _lengthY));
            }
      else  {
            *grips = n;
            *defaultGrip = n - 1;
            for (int i = 0; i < n; ++i)
                  grip[i].translate(cp + QPointF(path.elementAt(i).x * sp, path.elementAt(i).y * sp));

            }
      }
}