units.h

// SPDX-FileCopyrightText: © 2025 Alexandros Theodotou <alex@zrythm.org>
// SPDX-License-Identifier: LicenseRef-ZrythmLicense
 
#pragma once
 
#include <au/au.hh>
 
namespace zrythm::units
{
 
// Define base dimensions for sample and tick
// Using unique indices based on Unix epoch timestamps for uniqueness
struct SampleBaseDim : au::base_dim::BaseDimension<1737814550>
{
}; // 2025-01-25 13:05:50 UTC
struct TickBaseDim : au::base_dim::BaseDimension<1737814551>
{
}; // 2025-01-25 13:05:51 UTC
 
// Define sample unit with its own dimension
struct Sample : au::UnitImpl<au::Dimension<SampleBaseDim>>
{
  static constexpr const char label[] = "sample";
};
constexpr auto sample = au::SingularNameFor<Sample>{};
constexpr auto samples = au::QuantityMaker<Sample>{};
 
// Define sample quantity types
using sample_t = au::QuantityI64<Sample>;
using precise_sample_t = au::QuantityD<Sample>;
 
// Define tick unit with its own dimension
struct Tick : au::UnitImpl<au::Dimension<TickBaseDim>>
{
  static constexpr const char label[] = "tick";
};
constexpr auto tick = au::SingularNameFor<Tick>{};
constexpr auto ticks = au::QuantityMaker<Tick>{};
 
// Define tick quantity types
using tick_t = au::QuantityI64<Tick>;
using precise_tick_t = au::QuantityD<Tick>;
 
// Define PPQ constant (960 ticks per quarter note)
constexpr tick_t PPQ = ticks (960);
 
// Define quarter_note unit as 960 ticks using unit expression
struct QuarterNote : decltype (Tick{} * au::mag<960> ())
{
  static constexpr const char label[] = "quarterNote";
};
constexpr auto quarter_note = au::SingularNameFor<QuarterNote>{};
constexpr auto quarter_notes = au::QuantityMaker<QuarterNote>{};
 
// Define sample rate as a compound unit (samples per second)
using SampleRate = decltype (Sample{} / au::Seconds{});
constexpr auto sample_rate = samples / au::second;
using sample_rate_t = au::QuantityI<SampleRate>;
using precise_sample_rate_t = au::QuantityD<SampleRate>;
 
// Define precise second using Au's built-in seconds
constexpr auto seconds = au::seconds;
using precise_second_t = au::QuantityD<au::Seconds>;
}