qmk-firmware/keyboards/keebwerk/nano_slider/keymaps/midi2vol/keymap.c

/* Copyright 2020 Duckle, 2021 Jesús Vallejo
 *
 * This program 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 2 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 <http://www.gnu.org/licenses/>.
 */


#include QMK_KEYBOARD_H
#include "analog.h"
#include "qmk_midi.h"

/*
This keymap works with midi2vol: linux version  https://github.com/jesusvallejo/Midi2Vol-Linux  
and windows version https://github.com/jesusvallejo/Midi2Vol

Enables the user to change the volume on the host computer if running midi2vol software.

Example to extend usability is provided check VLC in: enum custom_keycodes {} and bool process_record_user(uint16_t keycode, keyrecord_t *record) {}
Remember to give allways the new volume control a hex value not used by other volume control, 
and add it to the midi2vol software.
Check respective midi2vol readme on how to do so.In linux change config.json,in windows you can use configuration option.

A compiled version of this keymap is provided in here: https://github.com/jesusvallejo/nanokeymaps/

*/

uint8_t midi2vol = 0x3E;

/* Defines names for use in layer keycodes and the keymap */

enum custom_layers {
    _MEDIA,    /* Controls Pause, Mute , Forward ... */
    _NAV,      /* Nav arrows, Enter, Space*/
    _VOLUME,    /* Changes midi2vol int to interface with midi2vol program: Chrome Volume, General Volume */
    _DISCORD,  /* FXX unsused keys to interface with Discord: Mute , Silence */
    _LIGHTS,   /* Edits underglow and retroilumination */
    _EDIT,     /* Cut, Copy ,Paste */
    _RESET,    /* Layer to set nano in bootloader mode */
    _TOOGLE,   /* Momentary layer to switch between layers */
};



/* Defines the keycodes used by our macros in process_record_user */
enum custom_keycodes { /* In order to add more volume controls, add here a custom keycode, ex: VLC */
    DEFAULT= SAFE_RANGE,SPOTIFY,DISCORD,CHROME/*,VLC*/
};


const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
    /* Base */
    [_MEDIA] = LAYOUT(
        MO(_TOOGLE),
        KC_MPLY, KC_MNXT,  KC_COPY,
        KC_MUTE,  KC_MPRV, KC_PASTE, KC_ENTER
    ),
    [_NAV] = LAYOUT(
        MO(_TOOGLE),
        KC_SPC, KC_UP, KC_BSPACE,
        KC_LEFT, KC_DOWN, KC_RIGHT, KC_ENTER      
    ),
    [_VOLUME] = LAYOUT(
        MO(_TOOGLE),
        SPOTIFY, DISCORD, CHROME,
        KC_NO, KC_NO, KC_NO, DEFAULT
    ),
    [_DISCORD] = LAYOUT(
        MO(_TOOGLE),
        KC_F18, KC_F19, KC_F20,
        KC_F21, KC_F22, KC_F23, KC_F24
    ),
    [_LIGHTS] = LAYOUT(
        MO(_TOOGLE),
        RGB_TOG, RGB_MOD, RGB_VAI,
        RGB_SAI, BL_BRTG, BL_STEP, KC_LSFT
    ),
    [_EDIT] = LAYOUT(
        MO(_TOOGLE),
        KC_MENU, KC_CUT, KC_COPY,
        KC_FIND, KC_UNDO, KC_PASTE, KC_MPLY
    ),
    [_RESET] = LAYOUT(
        MO(_TOOGLE),
        KC_NO, KC_NO, KC_NO,
        KC_NO, KC_NO, KC_NO, RESET 
    ),
    [_TOOGLE] = LAYOUT(
        MO(_TOOGLE),
        TO(_MEDIA),    TO(_NAV),    TO(_VOLUME),
        TO(_DISCORD),    TO(_LIGHTS),    TO(_EDIT),    TO(_RESET)
    )
};
/* In order to add more volume controls, add here code to detect custom keycode, ex: VLC */
bool process_record_user(uint16_t keycode, keyrecord_t *record) { 
    switch (keycode) {
        case DEFAULT:
            if (record->event.pressed) {
                /* when keycode DEFAULT is pressed */
                midi2vol= 0x3E;
            } else {
                /* when keycode DEFAULT is released */
            }
            break;
        case SPOTIFY:
            if (record->event.pressed) {                
                midi2vol= 0x3F;
            }
            break;
        case DISCORD:
            if (record->event.pressed) {
                
                midi2vol= 0x40;
            } 
            break;
        case CHROME:
            if (record->event.pressed) {
                
                midi2vol= 0x41;
            }
            break;
        /*
        case VLC:
            if (record->event.pressed) {
                midi2vol= 0x42;
            }
            break;
        */
    }
    return true;
}

uint8_t divisor = 0;


void slider(void) {
    if (divisor++) { /* only run the slider function 1/256 times it's called */
        return;
    }
    midi_send_cc(&midi_device, 2, midi2vol, 0x7F - (analogReadPin(SLIDER_PIN) >> 3));
}

void matrix_scan_user(void) {
    slider();
}