portapack-mayhem/firmware/common/complex.hpp

/*
 * Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
 *
 * This file is part of PortaPack.
 *
 * 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, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef __COMPLEX_H__
#define __COMPLEX_H__

#include <cstdint>
#include <complex>
#include <cmath>

constexpr float pi{3.141592653589793238462643383279502884f};

namespace std {

template <>
struct complex<int8_t> {
   public:
    typedef int8_t value_type;
    typedef uint16_t rep_type;

    // constexpr complex(
    // 	rep_type r
    // ) : _rep { r }
    // {
    // }

    constexpr complex(
        int8_t re = 0,
        int8_t im = 0)
        : _v{re, im} {
    }

    // constexpr complex(
    // 	const complex& o
    // ) : _rep { o._rep }
    // {
    // }

    constexpr int8_t real() const { return _v[0]; }
    constexpr int8_t imag() const { return _v[1]; }

    void real(int8_t v) { _v[0] = v; }
    void imag(int8_t v) { _v[1] = v; }

    constexpr uint16_t __rep() const {
        return _rep;
    }

   private:
    union {
        value_type _v[2];
        rep_type _rep;
    };
};

template <>
struct complex<int16_t> {
   public:
    typedef int16_t value_type;
    typedef uint32_t rep_type;

    // constexpr complex(
    // 	rep_type r
    // ) : _rep { r }
    // {
    // }

    constexpr complex(
        int16_t re = 0,
        int16_t im = 0)
        : _v{re, im} {
    }

    // constexpr complex(
    // 	const complex& o
    // ) : _rep { o._rep }
    // {
    // }

    constexpr int16_t real() const { return _v[0]; }
    constexpr int16_t imag() const { return _v[1]; }

    void real(int16_t v) { _v[0] = v; }
    void imag(int16_t v) { _v[1] = v; }

    template <class X>
    complex<int16_t>& operator+=(const complex<X>& other) {
        _v[0] += other.real();
        _v[1] += other.imag();
        return *this;
    }

    constexpr uint32_t __rep() const {
        return _rep;
    }

    constexpr operator std::complex<float>() const {
        return {
            static_cast<float>(_v[0]),
            static_cast<float>(_v[1])};
    }

   private:
    union {
        value_type _v[2];
        rep_type _rep;
    };
};

} /* namespace std */

using complex8_t = std::complex<int8_t>;
using complex16_t = std::complex<int16_t>;
using complex32_t = std::complex<int32_t>;

static_assert(sizeof(complex8_t) == 2, "complex8_t size wrong");
static_assert(sizeof(complex16_t) == 4, "complex16_t size wrong");
static_assert(sizeof(complex32_t) == 8, "complex32_t size wrong");

#endif /*__COMPLEX_H__*/