sfizz/sfizz/SfzHelpers.h

// Copyright (c) 2019, Paul Ferrand
// All rights reserved.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:

// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#pragma once
#include <absl/types/optional.h>
#include <absl/strings/string_view.h>
//#include <string>
#include <array>
#include <cmath>

namespace sfz
{

using CCValueArray = std::array<uint8_t, 128>;
using CCValuePair = std::pair<uint8_t, float> ;
using CCNamePair = std::pair<uint8_t, std::string>;

template<class T>
inline constexpr float centsFactor(T cents, T centsPerOctave = 1200)
{
    return std::pow(2.0f, static_cast<float>(cents) / centsPerOctave);
}

template<class T>
inline constexpr float normalizeCC(T ccValue)
{
    static_assert(std::is_integral<T>::value, "Requires an integral T");
    return static_cast<float>(std::min(std::max(ccValue, static_cast<T>(0)), static_cast<T>(127))) / 127.0f;
}

template<class T>
inline constexpr float normalizePercents(T percentValue)
{
    return std::min(std::max(static_cast<float>(percentValue), 0.0f), 100.0f) / 100.0f;
}

template<class T>
inline constexpr float normalizeNegativePercents(T percentValue)
{
    return std::min(std::max(static_cast<float>(percentValue), -100.0f), 100.0f) / 100.0f;
}

inline float ccSwitchedValue(const CCValueArray& ccValues, const absl::optional<CCValuePair>& ccSwitch, float value) noexcept
{
    if (ccSwitch)
        return value + ccSwitch->second * normalizeCC(ccValues[ccSwitch->first]);
    else
        return value;
}

absl::optional<uint8_t> readNoteValue(const absl::string_view& value);

} // namespace sfz