+ public static void setTimeSig(long tick, int numerator, int denominator) {
+ // Checks for a time signature event at the given tick position.
+ MidiEvent timeSigEvent = null;
+ Iterator it = timeSignatures.iterator();
+ while(it.hasNext()) {
+ MidiEvent nextTimeSigEvent = (MidiEvent)it.next();
+ if (nextTimeSigEvent.getTick() == tick) {
+ timeSigEvent = nextTimeSigEvent;
+ break;
+ }
+ }
+
+ // If none was found, creates and adds a new one.
+ if (timeSigEvent == null) {
+ timeSigEvent = new MidiEvent(new MetaMessage(), tick);
+ (seq.getTracks())[0].add(timeSigEvent);
+ timeSignatures.add(timeSigEvent);
+ Collections.sort(timeSignatures, new MidiEventComparator());
+ }
+
+ // Sets the time signature of the event (found or created).
+ try {
+ ((MetaMessage)timeSigEvent.getMessage()).setMessage(88, encodeTimeSig(numerator, denominator), 4);
+ } catch (InvalidMidiDataException e) {}
+ }
+
+ /**
+ * Calculates the position (measures, beats, ticks) in the current sequence for the given tick position.
+ * @param tickPosition the tick position for which to calculate the position
+ * @return an array of integers where index 0 is measures, 1 is beats and 2 is ticks.
+ */
+ public static int[] getPositionForTicks(long tickPosition) {
+ int ticksPerBeat = seq.getResolution();
+ long measures = 0, beats = 0, ticks = 0;
+
+ // Counts for each time signature change up to the last one before the given tick position.
+ Iterator it = timeSignatures.iterator();
+ MidiEvent lastTSEvent = (MidiEvent)it.next();
+ while(it.hasNext()) {
+ MidiEvent nextTSEvent = (MidiEvent)it.next();
+ if (nextTSEvent.getTick() > tickPosition) break;
+ long tickDiff = nextTSEvent.getTick() - lastTSEvent.getTick();
+ int[] ts = decodeTimeSig(((MetaMessage)lastTSEvent.getMessage()).getData());
+ int beatsPerMeasure = ts[0] * (4 / ts[1]);
+ long thisTSMeasures = tickDiff / (beatsPerMeasure * ticksPerBeat);
+ measures += thisTSMeasures;
+ long thisTSBeats = (tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat) / ticksPerBeat;
+ beats += thisTSBeats;
+ ticks += tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat - thisTSBeats * ticksPerBeat;
+ lastTSEvent = nextTSEvent;
+ }
+
+ // Counts from the given tick position to the last time signature change before it.
+ long tickDiff = tickPosition - lastTSEvent.getTick();
+ int[] ts = decodeTimeSig(((MetaMessage)lastTSEvent.getMessage()).getData());
+ int beatsPerMeasure = ts[0] * (4 / ts[1]);
+ long thisTSMeasures = tickDiff / (beatsPerMeasure * ticksPerBeat);
+ measures += thisTSMeasures;
+ long thisTSBeats = (tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat) / ticksPerBeat;
+ beats += thisTSBeats;
+ ticks += tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat - thisTSBeats * ticksPerBeat;
+
+ // Corrects any overflows.
+ if (ticks > ticksPerBeat) {
+ beats += Math.floor(ticks / ticksPerBeat);
+ ticks = ticks % ticksPerBeat;
+ }
+ if (beats > beatsPerMeasure) {
+ measures += Math.floor(beats / beatsPerMeasure);
+ beats = beats % beatsPerMeasure;
+ }
+
+ // Returns the calculated values.
+ int[] pos = {(int)measures, (int)beats, (int)ticks};
+ return pos;