encoders.h

/*
 * Copyright © 2020-2023 Synthstrom Audible Limited
 *
 * This file is part of The Synthstrom Audible Deluge Firmware.
 *
 * The Synthstrom Audible Deluge Firmware 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 3 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 <https://www.gnu.org/licenses/>.
 */
 
#pragma once
 
#include "OSLikeStuff/scheduler_api.h"
#include <atomic>
#include <cstddef>
#include <cstdint>
 
namespace deluge::hid::encoders {

class DetentedEncoder {
public:
    DetentedEncoder() = default;
    DetentedEncoder(const DetentedEncoder&) = delete;
    DetentedEncoder& operator=(const DetentedEncoder&) = delete;
 
    void applyEdges(int8_t edges);

    bool pending() const { return pos.load(std::memory_order_relaxed) != 0; }

    int32_t take();

    void restore(int32_t val) { pos.fetch_add(val, std::memory_order_relaxed); }
 
private:
    int32_t edgeAccumulator = 0; 
    std::atomic_int32_t pos = 0; 
};

class ContinuousEncoder {
public:
    ContinuousEncoder() = default;
    ContinuousEncoder(const ContinuousEncoder&) = delete;
    ContinuousEncoder& operator=(const ContinuousEncoder&) = delete;
 
    void applyEdges(int8_t edges) { pos.fetch_add(edges, std::memory_order_relaxed); }

    bool pending() const { return pos.load(std::memory_order_relaxed) != 0; }

    int8_t take();

    double calcNextKnobSpeed(int8_t offset);
 
private:
    std::atomic_int8_t pos = 0;   
    double currentKnobSpeed{0.0}; // Used for encoder acceleration
};
 
// ── Named encoder globals ─────────────────────────────────────────────────
 
extern DetentedEncoder scrollY;
extern DetentedEncoder scrollX;
extern DetentedEncoder tempo;
extern DetentedEncoder select;
extern ContinuousEncoder mod0; 
extern ContinuousEncoder mod1; 
 
// ── Array-index access for iteration ─────────────────────────────────────
 
constexpr size_t kNumFunctionEncoders = 4;
constexpr size_t kNumModEncoders = 2;
 
DetentedEncoder& functionEncoderAt(size_t i); 
ContinuousEncoder& modEncoderAt(size_t i);    
 
// ── Shared timestamp ──────────────────────────────────────────────────────

extern uint32_t timeModEncoderLastTurned[];
 
// ── Lifecycle ─────────────────────────────────────────────────────────────
 
void init();

extern TaskID EncoderTaskID;
 
} // namespace deluge::hid::encoders