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#include "importmidi_swing.h"
#include "libmscore/score.h"
#include "libmscore/chordrest.h"
#include "libmscore/stafftext.h"
#include "libmscore/element.h"
#include "libmscore/segment.h"
#include "libmscore/measure.h"
#include "libmscore/staff.h"
#include "libmscore/tuplet.h"
#include "importmidi_fraction.h"
namespace Ms {
namespace Swing {
class SwingDetector
{
public:
SwingDetector(MidiOperations::Swing st);
void add(ChordRest *cr);
bool wasSwingApplied() const { return swingApplied; }
private:
std::vector<ChordRest *> elements;
ReducedFraction sumLen;
const ReducedFraction FULL_LEN = {1, 4};
MidiOperations::Swing swingType;
bool swingApplied = false;
void reset();
void append(ChordRest *cr);
void checkNormalSwing();
void checkShuffle();
void applySwing();
bool areAllTuplets() const;
bool areAllNonTuplets() const;
};
SwingDetector::SwingDetector(MidiOperations::Swing st)
: swingType(st)
{
}
void SwingDetector::add(ChordRest *cr)
{
if (elements.empty()) {
if (ReducedFraction(cr->globalTicks()) >= FULL_LEN)
return;
const int tickInBar = (cr->tick() - cr->measure()->tick()).ticks();
if (tickInBar % MScore::division == 0)
append(cr);
}
else {
if (sumLen + ReducedFraction(cr->globalTicks()) > FULL_LEN) {
reset();
return;
}
append(cr);
if (sumLen == FULL_LEN) {
// check for swing patterns
switch (swingType) {
case MidiOperations::Swing::SWING:
checkNormalSwing();
break;
case MidiOperations::Swing::SHUFFLE:
checkShuffle();
break;
default:
break;
}
reset();
}
}
}
void SwingDetector::reset()
{
elements.clear();
sumLen = ReducedFraction(Fraction(0,1));
}
void SwingDetector::append(ChordRest *cr)
{
if (cr->isChord() || cr->isRest()) {
elements.push_back(cr);
sumLen += ReducedFraction(cr->globalTicks());
}
}
void SwingDetector::checkNormalSwing()
{
if (elements.size() == 2
&& areAllTuplets()
&& (elements[0]->isChord() || elements[1]->type() == ElementType::CHORD)
&& elements[0]->ticks().reduced() == Fraction(1, 4)
&& elements[1]->ticks().reduced() == Fraction(1, 8))
{
// swing with two 8th notes
// or 8th note + 8th rest
// or 8th rest + 8th note
applySwing();
}
else if (elements.size() == 3
&& elements[0]->isChord()
&& elements[1]->isRest()
&& elements[2]->isChord()
&& elements[0]->ticks().reduced() == Fraction(1, 8)
&& elements[1]->ticks().reduced() == Fraction(1, 8)
&& elements[2]->ticks().reduced() == Fraction(1, 8))
{
// swing with two 8th notes
applySwing();
}
}
void SwingDetector::checkShuffle()
{
if (elements.size() == 2
&& areAllNonTuplets()
&& elements[0]->isChord()
&& (elements[1]->isChord()
|| elements[1]->isRest())
&& elements[0]->ticks().reduced() == Fraction(3, 16) // dotted 8th
&& elements[1]->ticks().reduced() == Fraction(1, 16))
{
// swing with two 8th notes
// or 8th note + 8th rest
applySwing();
}
}
void SwingDetector::applySwing()
{
if (elements.size() != 2 && elements.size() != 3)
return;
Tuplet *tuplet = nullptr;
for (ChordRest *el: elements) {
el->setDurationType(TDuration::DurationType::V_EIGHTH);
el->setTicks(Fraction(1, 8));
el->setDots(0);
if (el->tuplet()) {
if (!tuplet)
tuplet = el->tuplet();
tuplet->remove(el);
el->setTuplet(nullptr);
}
}
const ChordRest *first = elements.front();
const int startTick = first->segment()->tick().ticks();
ChordRest *last = elements.back();
last->segment()->remove(last);
Segment *s = last->measure()->getSegment(SegmentType::ChordRest, Fraction::fromTicks(startTick + MScore::division / 2));
s->add(last);
if (elements.size() == 3) {
// remove central rest
ChordRest *cr = elements[1];
cr->score()->removeElement(cr);
delete cr;
}
if (tuplet) {
// delete tuplet
delete tuplet;
tuplet = nullptr;
}
if (!swingApplied)
swingApplied = true;
}
bool SwingDetector::areAllTuplets() const
{
for (const auto &el: elements) {
if (!el->tuplet())
return false;
}
return true;
}
bool SwingDetector::areAllNonTuplets() const
{
for (const auto &el: elements) {
if (el->tuplet())
return false;
}
return true;
}
// ---------------------------------------------------------------
QString swingCaption(MidiOperations::Swing swingType)
{
QString caption;
switch (swingType) {
case MidiOperations::Swing::SWING:
caption = "Swing";
break;
case MidiOperations::Swing::SHUFFLE:
caption = "Shuffle";
break;
case MidiOperations::Swing::NONE:
break;
}
return caption;
}
void detectSwing(Staff *staff, MidiOperations::Swing swingType)
{
Score *score = staff->score();
const int strack = staff->idx() * VOICES;
SwingDetector swingDetector(swingType);
for (Segment *seg = score->firstSegment(SegmentType::ChordRest); seg;
seg = seg->next1(SegmentType::ChordRest)) {
for (int voice = 0; voice < VOICES; ++voice) {
ChordRest *cr = static_cast<ChordRest *>(seg->element(strack + voice));
if (!cr)
continue;
swingDetector.add(cr);
}
}
if (swingDetector.wasSwingApplied()) {
// add swing label to the score
StaffText* st = new StaffText(score, Tid::STAFF);
st->setPlainText(swingCaption(swingType));
Segment* seg = score->firstSegment(SegmentType::ChordRest);
st->setParent(seg);
st->setTrack(strack); // voice == 0
score->addElement(st);
}
}
} // namespace Swing
} // namespace Ms
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