qmk_firmware/keyboards/maartenwut/ta65/keymaps/default/keymap.c

#include QMK_KEYBOARD_H

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

[0] = LAYOUT_all(
  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_BSLS, KC_BSPC, KC_INS,
  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_BSLS,          KC_DEL,
  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_BSLS,  KC_ENT,           KC_PGUP,
  KC_LSFT, KC_NUBS, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,   KC_COMM,  KC_DOT,  KC_SLSH, KC_RSFT,  KC_UP,            KC_PGDN,
  KC_LCTL, KC_LGUI, KC_LALT,                            KC_SPC,                             KC_RALT, MO(1),   KC_RCTRL, KC_LEFT, KC_DOWN, KC_RGHT),

[1] = LAYOUT_all(
  RESET,   _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,  _______, _______, _______,
  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,  _______,          _______,
  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,  _______,          _______,
  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,  _______,          _______,
  _______, _______, _______,                            _______,                            _______, _______, _______,  _______, _______, _______),

};

void encoder_update_user(uint8_t index, bool clockwise) {
  if (index == 0) { /* First encoder */
    switch(get_highest_layer(layer_state)){
      case 0: //Layer 0
        if (!clockwise) { // Remove ! to reverse direction
          tap_code(KC_VOLU);
        } else {
          tap_code(KC_VOLD);
        }
        break;
      case 1: //Layer 1
        if (!clockwise) {
          tap_code(KC_WH_U);
        } else {
          tap_code(KC_WH_D);
        }
        break;
      default:
        if (!clockwise) {
          tap_code(KC_VOLU);
        } else {
          tap_code(KC_VOLD);
        }
        break;
    }
  }
}