qmk_firmware_custom/keyboards/gh60/keymaps/default/keymap.c

#include QMK_KEYBOARD_H

// Fillers to make layering more clear
#define _______ KC_TRNS

const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {

  /* 0: qwerty */
  LAYOUT(
    KC_ESC,  KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_MINS, KC_EQL,  KC_GRV,
    KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_LBRC, KC_RBRC, KC_BSPC,
    KC_CAPS, KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT, KC_NO,   KC_ENT,
    KC_LSFT, F(1),    KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, F(0),    KC_RSFT,
    KC_LCTL, KC_LGUI, KC_LALT,                   KC_SPC,                             KC_BSLS, KC_RALT, KC_RGUI, KC_APP,  KC_RCTL
  ),
  /* 1: fn */
  LAYOUT(
    KC_ESC,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  _______,
    _______, _______, KC_UP,   _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, KC_LEFT, KC_DOWN, KC_RGHT, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, _______,                   _______,                            _______, _______, _______, _______, _______
  ),

    /* 2: arrows */
  LAYOUT(
    _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, KC_UP,
    _______, _______, _______,                   _______,                            _______, _______, KC_LEFT, KC_DOWN, KC_RGHT
  ),

};

const uint16_t PROGMEM fn_actions[] = {
    [0] = ACTION_LAYER_MOMENTARY(1),  // to Fn overlay
    [1] = ACTION_LAYER_TOGGLE(2),     // toggle arrow overlay
};

const macro_t *action_get_macro(keyrecord_t *record, uint8_t id, uint8_t opt)
{
  // MACRODOWN only works in this function
      switch(id) {
        case 0:
          if (record->event.pressed) {
            register_code(KC_RSFT);
          } else {
            unregister_code(KC_RSFT);
          }
        break;
      }
    return MACRO_NONE;
};

void matrix_scan_user(void) {

//Layer LED indicators
    uint32_t layer = layer_state;

    if (layer & (1<<1)) {
        gh60_wasd_leds_on();
        gh60_fn_led_on();
    } else {
        gh60_wasd_leds_off();
        gh60_fn_led_off();
    }

    if (layer & (1<<2)) {
        gh60_poker_leds_on();
        gh60_esc_led_on();
    } else {
        gh60_poker_leds_off();
        gh60_esc_led_off();
    }

};