qmk_firmware/keyboards/atreus/keymaps/default/keymap.c

// this is the style you want to emulate.
// This is the canonical layout file for the Quantum project. If you want to add another keyboard,

#include QMK_KEYBOARD_H

#undef S
#undef A
#undef C
#undef G

#define S LSFT_T
#define A LALT_T
#define C LCTL_T
#define G LGUI_T
#define R RALT_T

#define RALT_A RALT_T(KC_A)
#define ALT_S LALT_T(KC_S)
#define CTL_D LCTL_T(KC_D)
#define GUI_F LGUI_T(KC_F)

#define GUI_J LGUI_T(KC_J)
#define CTL_K LCTL_T(KC_K)
#define ALT_L LALT_T(KC_L)
#define RALT_SCLN RALT_T(KC_SCLN)

#define MUTE LGUI(KC_C)

enum layers {
    DEF,
    SYM,
    NAV,
    NUM,
};

#define LA_SYM MO(SYM)
#define LA_NAV MO(NAV)

const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
    [DEF] = LAYOUT(
        KC_Q,   KC_W,   KC_E,   KC_R,   KC_T,                   KC_Y,   KC_U,   KC_I,   KC_O,   KC_P,
        S(KC_A),A(KC_S),C(KC_D),G(KC_F),R(KC_G),                R(KC_H),G(KC_J),C(KC_K),A(KC_L),S(KC_SCLN),
        KC_Z,   KC_X,   KC_C,   KC_V,   KC_B,   XXXXXXX,XXXXXXX,KC_N,   KC_M,   KC_COMM,KC_DOT, KC_QUOT,
        XXXXXXX,XXXXXXX,XXXXXXX,LA_NAV, KC_LSFT,XXXXXXX,XXXXXXX,KC_SPC, LA_SYM, XXXXXXX,XXXXXXX,XXXXXXX
    ),

    [SYM] = LAYOUT(
        KC_ESC, KC_LBRC,KC_LCBR,KC_LPRN,KC_TILD,                KC_CIRC,KC_RPRN,KC_RCBR,KC_RBRC,KC_GRV,
        KC_MINS,KC_ASTR,KC_EQL, KC_UNDS,KC_DLR,                 R(KC_HASH),G(KC_NO),C(KC_NO),A(KC_NO),S(KC_NO),
        KC_PLUS,KC_PIPE,KC_AT,  KC_SLSH,KC_PERC,XXXXXXX,XXXXXXX,KC_AMPR,KC_BSLS,RALT(KC_SLSH),KC_QUES,KC_EXLM,
        XXXXXXX,XXXXXXX,XXXXXXX,_______,_______,XXXXXXX,XXXXXXX,_______,_______,XXXXXXX,XXXXXXX,XXXXXXX
    ),

    [NAV] = LAYOUT(
        KC_TAB, XXXXXXX,KC_VOLU,KC_VOLD,MUTE,                   XXXXXXX,KC_CAPS,XXXXXXX,XXXXXXX,RESET,
        S(KC_NO),A(KC_NO),C(KC_NO),G(KC_NO),KC_BSPC,            KC_LEFT,KC_DOWN,KC_UP,  KC_RGHT,S(KC_NO),
        XXXXXXX,XXXXXXX,XXXXXXX,XXXXXXX,KC_PSCR,XXXXXXX,XXXXXXX,XXXXXXX,KC_PGDN,KC_PGUP,XXXXXXX,KC_ENT,
        XXXXXXX,XXXXXXX,XXXXXXX,_______,_______,XXXXXXX,XXXXXXX,_______,_______,XXXXXXX,XXXXXXX,XXXXXXX
    ),

    [NUM] = LAYOUT(
        KC_1,   KC_2,   KC_3,   KC_4,   KC_5,                   KC_6,   KC_7,   KC_8,   KC_9,   KC_0,
        S(KC_NO),A(KC_NO),C(KC_NO),G(KC_NO),R(KC_F11),          R(KC_F12),G(KC_NO),C(KC_NO),A(KC_NO),S(KC_NO),
        KC_F1,  KC_F2,  KC_F3,  KC_F4,  KC_F5,  XXXXXXX,XXXXXXX,KC_F6,  KC_F7,  KC_F8,  KC_F9,  KC_F10,
        XXXXXXX,XXXXXXX,XXXXXXX,_______,_______,XXXXXXX,XXXXXXX,_______,_______,XXXXXXX,XXXXXXX,XXXXXXX
    )
};

layer_state_t layer_state_set_user(layer_state_t state) {
    return update_tri_layer_state(state, SYM, NAV, NUM);
}