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#include "track/beats.h"
namespace mixxx {
int Beats::numBeatsInRange(audio::FramePos startPosition, audio::FramePos endPosition) const {
audio::FramePos lastPosition = audio::kStartFramePos;
int i = 1;
while (lastPosition < endPosition) {
lastPosition = findNthBeat(startPosition, i);
if (!lastPosition.isValid()) {
break;
}
i++;
}
return i - 2;
};
audio::FramePos Beats::findNBeatsFromPosition(audio::FramePos position, double beats) const {
audio::FramePos prevBeatPosition;
audio::FramePos nextBeatPosition;
if (!findPrevNextBeats(position, &prevBeatPosition, &nextBeatPosition, true)) {
return position;
}
const audio::FrameDiff_t fromFractionBeats = (position - prevBeatPosition) /
(nextBeatPosition - prevBeatPosition);
const audio::FrameDiff_t beatsFromPrevBeat = fromFractionBeats + beats;
const int fullBeats = static_cast<int>(beatsFromPrevBeat);
const audio::FrameDiff_t fractionBeats = beatsFromPrevBeat - fullBeats;
// Add the length between this beat and the fullbeats'th beat
// to the end position
audio::FramePos nthBeatPosition;
if (fullBeats > 0) {
nthBeatPosition = findNthBeat(nextBeatPosition, fullBeats);
} else {
nthBeatPosition = findNthBeat(prevBeatPosition, fullBeats - 1);
}
if (!nthBeatPosition.isValid()) {
return position;
}
// Add the fraction of the beat
if (fractionBeats != 0) {
nextBeatPosition = findNthBeat(nthBeatPosition, 2);
if (!nextBeatPosition.isValid()) {
return position;
}
nthBeatPosition += (nextBeatPosition - nthBeatPosition) * fractionBeats;
}
return nthBeatPosition;
};
} // namespace mixxx
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