arduino-joystick/Joystick.h

#ifndef _JOYSTICK_H_
#define _JOYSTICK_H_

#include <Arduino.h>
#include <Bounce2.h>
#include <Mux.h>

using namespace admux;

// If you're using the arduino-big-joystick firmware, these numbers can't be
// changed. If you're writing your own Report Descriptor, tune these to match by
// defining them *before* you include Joystick.h.
#ifndef JOYSTICK_NUM_AXES
#define JOYSTICK_NUM_AXES 8
#endif
#ifndef JOYSTICK_NUM_BUTTONS
#define JOYSTICK_NUM_BUTTONS 40
#endif
#define JOYSTICK_NUM_BYTES (JOYSTICK_NUM_BUTTONS+7)/8

#ifndef MAX_MUX
#define MAX_MUX 3
#endif

enum ButtonType {
  BUTTON_PASSTHRU = 0x1, // always use the (debounced) absolute state of the input
  BUTTON_PULSED = 0x2, // on button press, send an on signal followed immediately by an off signal.
  BUTTON_PULSED_DOUBLE_ACTION = 0x4, // Send a button press twice - once for press and once for release.
  BUTTON_PULSED_DOUBLE_ACTION_SPLIT = 0x8, // Send two separate button presses - one button on press, another on release.
  BUTTON_LATCHED_MOMENTARY = 0x10
};

struct JoyReport {
  int16_t axis[JOYSTICK_NUM_AXES];
  uint8_t button[JOYSTICK_NUM_BYTES];
};

struct Button {
  ButtonType type;
  Bounce bouncer;
  uint8_t vbutton0;
  uint8_t vbutton1; // only used by BUTTON_PULSED_DOUBLE_ACTION_SPLIT
  bool pressed = false; // only used by BUTTON_LATCHED_MOMENTARY
  bool inverted = false; // if true, send button press on release and vice versa.

  // todo: this should probably be abstracted out from this struct...
  bool mux;
  uint8_t mux_id;
  uint8_t mux_channel;
};

bool operator ==(JoyReport a, JoyReport b);
bool operator !=(JoyReport a, JoyReport b);

class Joystick {
  public:
    Joystick(bool debug=false);
    void Init();
    void Update();

    // Add a button to the joystick.
    // Button types are documented in the ButtonType enum.
    // If `pullup` is true, your button should connect the pin to ground. (also be sure that your board supports INPUT_PULLUP on that pin)
    // If `pullup` is false, your button should connect the pin to VCC.
    // Mux parameters are ignored unless `mux` is true.
    void AddButton(uint8_t pin, ButtonType type, bool pullup=true, bool mux=false, uint8_t mux_id = 0; uint8_t mux_channel = 0);

    // Add an analog axis to the joystick. THIS METHOD IS NOT CURRENTLY TESTED OR SUPPORTED. It might work, but probably not.
    void AddAxis(uint8_t pin);

    // Add control for a multiplexer. To add a button that's connected via the multiplexer,
    // pass the mux's signal pin as the pin parameter to AddButton(), along with the mux* parameters.
    // mux_id is the array index of the mux (in the order you added them via AddMux())
    uint8_t AddMux(uint8_t signal_pin, uint8_t addr_pins[], uint8_t addr_width);
    
  private:
    void SetAxis(uint8_t axis, int16_t value);
    void PressButton(uint8_t button);
    void ReleaseButton(uint8_t button);
    void ReleaseAllButtons();
    void Write();

    void _ReleasePulsedButtons();
    void _UpdateButton(uint8_t index);
    void _UpdateAxis(uint8_t index);
    
    Button _buttons[JOYSTICK_NUM_BUTTONS];
    uint8_t _num_buttons;
    uint8_t _virtual_buttons; // a single user-defined button can have multiple virtual buttons.
    bool _have_pulsed_button;

    uint8_t _axes[JOYSTICK_NUM_AXES];
    uint8_t _num_axes;
    
    JoyReport _joyReport;
    bool _debug;

    Mux     _mux[MAX_MUX];
    uint8_t _num_mux;
};

// Internal use only.
#define _BUTTON_PULSED_TYPES (BUTTON_PULSED | BUTTON_PULSED_DOUBLE_ACTION | BUTTON_PULSED_DOUBLE_ACTION_SPLIT)

#endif