musique/lib/link/include/ableton/link/Tempo.hpp
2023-01-14 22:52:45 +01:00

126 lines
3.2 KiB
C++

/* Copyright 2016, Ableton AG, Berlin. All rights reserved.
*
* 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 <http://www.gnu.org/licenses/>.
*
* If you would like to incorporate Link into a proprietary software application,
* please contact <link-devs@ableton.com>.
*/
#pragma once
#include <ableton/link/Beats.hpp>
#include <chrono>
namespace ableton
{
namespace link
{
struct Tempo
{
Tempo() = default;
// Beats per minute
explicit Tempo(const double bpm)
: mValue(bpm)
{
}
Tempo(const std::chrono::microseconds microsPerBeat)
: mValue(60. * 1e6 / static_cast<double>(microsPerBeat.count()))
{
}
double bpm() const
{
return mValue;
}
std::chrono::microseconds microsPerBeat() const
{
return std::chrono::microseconds{std::llround(60. * 1e6 / bpm())};
}
// Given the tempo, convert a time to a beat value
Beats microsToBeats(const std::chrono::microseconds micros) const
{
return Beats{
static_cast<double>(micros.count()) / static_cast<double>(microsPerBeat().count())};
}
// Given the tempo, convert a beat to a time value
std::chrono::microseconds beatsToMicros(const Beats beats) const
{
return std::chrono::microseconds{
std::llround(beats.floating() * static_cast<double>(microsPerBeat().count()))};
}
// Model the NetworkByteStreamSerializable concept
friend std::uint32_t sizeInByteStream(const Tempo tempo)
{
return discovery::sizeInByteStream(tempo.microsPerBeat());
}
template <typename It>
friend It toNetworkByteStream(const Tempo tempo, It out)
{
return discovery::toNetworkByteStream(tempo.microsPerBeat(), std::move(out));
}
template <typename It>
static std::pair<Tempo, It> fromNetworkByteStream(It begin, It end)
{
auto result =
discovery::Deserialize<std::chrono::microseconds>::fromNetworkByteStream(
std::move(begin), std::move(end));
return std::make_pair(Tempo{std::move(result.first)}, std::move(result.second));
}
friend bool operator==(const Tempo lhs, const Tempo rhs)
{
return lhs.mValue == rhs.mValue;
}
friend bool operator!=(const Tempo lhs, const Tempo rhs)
{
return lhs.mValue != rhs.mValue;
}
friend bool operator<(const Tempo lhs, const Tempo rhs)
{
return lhs.mValue < rhs.mValue;
}
friend bool operator>(const Tempo lhs, const Tempo rhs)
{
return lhs.mValue > rhs.mValue;
}
friend bool operator<=(const Tempo lhs, const Tempo rhs)
{
return lhs.mValue <= rhs.mValue;
}
friend bool operator>=(const Tempo lhs, const Tempo rhs)
{
return lhs.mValue >= rhs.mValue;
}
private:
double mValue = 0;
};
} // namespace link
} // namespace ableton