qmk_firmware/docs/features/unicode.md

16 KiB

Unicode

With a little help from your OS, practically any Unicode character can be input using your keyboard.

Caveats

There are some limitations to this feature. Because there is no "standard" method of Unicode input across all operating systems, each of them require their own setup process on both the host and in the firmware, which may involve installation of additional software. This also means Unicode input will not "just work" when the keyboard is plugged into another device.

Usage

The core Unicode API can be used purely programmatically. However, there are also additional subsystems which build on top of it and come with keycodes to make things easier. See below for more details.

Add the following to your keymap's rules.mk:

UNICODE_COMMON = yes

Basic Configuration

Add the following to your config.h:

Define Default Description
UNICODE_KEY_MAC KC_LEFT_ALT The key to hold when beginning a Unicode sequence with the macOS input mode
UNICODE_KEY_LNX LCTL(LSFT(KC_U)) The key to tap when beginning a Unicode sequence with the Linux input mode
UNICODE_KEY_WINC KC_RIGHT_ALT The key to hold when beginning a Unicode sequence with the WinCompose input mode
UNICODE_SELECTED_MODES -1 A comma separated list of input modes for cycling through
UNICODE_CYCLE_PERSIST true Whether to persist the current Unicode input mode to EEPROM
UNICODE_TYPE_DELAY 10 The amount of time to wait, in milliseconds, between Unicode sequence keystrokes

Audio Feedback

If you have the Audio feature enabled on your board, you can configure it to play sounds when the input mode is changed.

Add the following to your config.h:

Define Default Description
UNICODE_SONG_MAC n/a The song to play when the macOS input mode is selected
UNICODE_SONG_LNX n/a The song to play when the Linux input mode is selected
UNICODE_SONG_BSD n/a The song to play when the BSD input mode is selected
UNICODE_SONG_WIN n/a The song to play when the Windows input mode is selected
UNICODE_SONG_WINC n/a The song to play when the WinCompose input mode is selected

Input Subsystems

Each of these subsystems have their own pros and cons in terms of flexibility and ease of use. Choose the one that best fits your needs.

::::tabs

=== Basic

This is the easiest to use, albeit somewhat limited. It supports code points up to U+7FFF, which covers characters for most modern languages (including East Asian), as well as many symbols, but does not include emoji.

To enable Basic Unicode, add the following to your rules.mk:

UNICODE_ENABLE = yes

You can then add UC(c) keycodes to your keymap, where c is the code point of the desired character (in hexadecimal - the U+ prefix will not work). For example, UC(0x40B) will output Ћ, and UC(0x30C4) will output .

=== Unicode Map

Unicode Map supports all possible code points (up to U+10FFFF). Here, the code points are stored in a separate mapping table (which may contain at most 16,384 entries), instead of directly in the keymap.

To enable Unicode Map, add the following to your rules.mk:

UNICODEMAP_ENABLE = yes

Then, you will need to create a mapping table in your keymap.c, and (optionally) an enum for naming the array indices, like so:

enum unicode_names {
    BANG,
    IRONY,
    SNEK
};

const uint32_t PROGMEM unicode_map[] = {
    [BANG]  = 0x203D,  // ‽
    [IRONY] = 0x2E2E,  // ⸮
    [SNEK]  = 0x1F40D, // 🐍
};

Finally, add UM(i) keycodes to your keymap, where i is an index into the unicode_map[] array. If you defined the enum above, you can use those names instead, for example UM(BANG) or UM(SNEK).

Lower and Upper Case Pairs

Some writing systems have lowercase and uppercase variants of each character, such as å and Å. To make inputting these characters easier, you can use the UP(i, j) keycode in your keymap, where i and j are the mapping table indices of the lowercase and uppercase characters, respectively. If you're holding down Shift or have Caps Lock turned on when you press the key, the uppercase character will be inserted; otherwise, the lowercase character will be inserted.

const uint32_t PROGMEM unicode_map[] = {
    [AE_LOWER] = 0x00E6,  // æ
    [AE_UPPER] = 0x00C6,  // Æ
};

This is most useful when creating a keymap for an international layout with special characters. Instead of having to put the lower and upper case versions of a character on separate keys, you can have them both on the same key. This helps blend Unicode keys in with regular keycodes.

Due to keycode size constraints, i and j can each only refer to one of the first 128 characters in your unicode_map. In other words, 0 ≤ i ≤ 127 and 0 ≤ j ≤ 127.

=== UCIS

As with Unicode Map, the UCIS method also supports all possible code points, and requires the use of a mapping table. However, it works much differently - Unicode characters are input by replacing a typed mnemonic.

To enable UCIS, add the following to your keymap's rules.mk:

UCIS_ENABLE = yes

Then, create a mapping table in your keymap.c:

const ucis_symbol_t ucis_symbol_table[] = UCIS_TABLE(
    UCIS_SYM("poop", 0x1F4A9),                // 💩
    UCIS_SYM("rofl", 0x1F923),                // 🤣
    UCIS_SYM("ukr", 0x1F1FA, 0x1F1E6),        // 🇺🇦
    UCIS_SYM("look", 0x0CA0, 0x005F, 0x0CA0)  // ಠ_ಠ
);

By default, each table entry may be up to three code points long. This can be changed by adding #define UCIS_MAX_CODE_POINTS n to your keymap's config.h.

To invoke UCIS input, the ucis_start() function must first be called (for example, in a custom "Unicode" keycode). Then, type the mnemonic for the mapping table entry (such as "rofl"), and hit Space or Enter. The "rofl" text will be backspaced and the emoji inserted.

::::

Input Modes

Unicode input works by typing a sequence of characters, similar to a macro. However, since this sequence depends on your OS, you will need to prepare both your host machine and QMK to recognise and send the correct Unicode input sequences respectively.

To set the list of enabled input modes, add the UNICODE_SELECTED_MODES define to your keymap's config.h, for example:

#define UNICODE_SELECTED_MODES UNICODE_MODE_LINUX
// or
#define UNICODE_SELECTED_MODES UNICODE_MODE_MACOS, UNICODE_MODE_WINCOMPOSE

These modes can then be cycled through using the UC_NEXT and UC_PREV keycodes. You can also switch to any input mode, even if it is not specified in UNICODE_SELECTED_MODES, using their respective keycodes.

If your keyboard has working EEPROM, it will remember the last used input mode and continue using it on the next power up. This can be disabled by defining UNICODE_CYCLE_PERSIST to false.

:::::tabs

==== macOS

Mode Name: UNICODE_MODE_MACOS

macOS has built-in support for Unicode input as its own input source. It supports all possible code points by way of surrogate pairs for code points above U+FFFF.

To enable, go to System Preferences → Keyboard → Input Sources, then add Unicode Hex Input to the list (under Other), and activate it from the input dropdown in the menu bar. Note that this may disable some Option-based shortcuts such as Option+Left and Option+Right.

==== Linux (IBus)

Mode Name: UNICODE_MODE_LINUX

For Linux distros with IBus, Unicode input is enabled by default, supports all possible code points, and works almost anywhere. Without IBus, it works under GTK apps, but rarely anywhere else.

Users who would like support in non-GTK apps without IBus may need to resort to a more indirect method, such as creating a custom keyboard layout.

==== Windows (WinCompose)

Mode Name: UNICODE_MODE_WINCOMPOSE

This mode requires a third-party tool called WinCompose. It supports all possible code points, and is the recommended input mode for Windows.

To enable, install the latest release from GitHub. Once installed, it will automatically run on startup. This works reliably under all versions of Windows supported by WinCompose.

==== Windows (HexNumpad)

Mode Name: UNICODE_MODE_WINDOWS

::: warning This input mode is not the "Alt code" system. Alt codes are not Unicode; they instead follow the Windows-1252 character set. :::

This is Windows' built-in hex numpad Unicode input mode. It only supports code points up to U+FFFF, and is not recommended due to reliability and compatibility issues.

To enable, run the following as an administrator, then reboot:

reg add "HKCU\Control Panel\Input Method" -v EnableHexNumpad -t REG_SZ -d 1

==== Emacs

Mode Name: UNICODE_MODE_EMACS

Emacs supports code point input with the insert-char command.

==== BSD

Mode Name: UNICODE_MODE_BSD

Not currently implemented. If you're a BSD user and want to contribute support for this input mode, please feel free!

:::::

Keycodes

Key Aliases Description
UC(c) Send Unicode code point c, up to 0x7FFF
UM(i) Send Unicode code point at index i in unicode_map
UP(i, j) Send Unicode code point at index i, or j if Shift/Caps is on
QK_UNICODE_MODE_NEXT UC_NEXT Cycle through selected input modes
QK_UNICODE_MODE_PREVIOUS UC_PREV Cycle through selected input modes in reverse
QK_UNICODE_MODE_MACOS UC_MAC Switch to macOS input
QK_UNICODE_MODE_LINUX UC_LINX Switch to Linux input
QK_UNICODE_MODE_WINDOWS UC_WIN Switch to Windows input
QK_UNICODE_MODE_BSD UC_BSD Switch to BSD input (not implemented)
QK_UNICODE_MODE_WINCOMPOSE UC_WINC Switch to Windows input using WinCompose
QK_UNICODE_MODE_EMACS UC_EMAC Switch to emacs (C-x-8 RET)

API

uint8_t get_unicode_input_mode(void)

Get the current Unicode input mode.

Return Value

The currently active Unicode input mode.


void set_unicode_input_mode(uint8_t mode)

Set the Unicode input mode.

Arguments

  • uint8_t mode
    The input mode to set.

void unicode_input_mode_step(void)

Change to the next Unicode input mode.


void unicode_input_mode_step_reverse(void)

Change to the previous Unicode input mode.


void unicode_input_mode_set_user(uint8_t input_mode)

User-level callback, invoked when the input mode is changed.

Arguments

  • uint8_t input_mode
    The new input mode.

void unicode_input_mode_set_kb(uint8_t input_mode)

Keyboard-level callback, invoked when the input mode is changed.

Arguments

  • uint8_t input_mode
    The new input mode.

void unicode_input_start(void)

Begin the Unicode input sequence. The exact behavior depends on the currently selected input mode:

  • macOS: Hold UNICODE_KEY_MAC
  • Linux: Tap UNICODE_KEY_LNX
  • WinCompose: Tap UNICODE_KEY_WINC, then U
  • HexNumpad: Hold Left Alt, then tap Numpad +
  • Emacs: Tap Ctrl+X, then 8, then Enter

This function is weakly defined, and can be overridden in user code.


void unicode_input_finish(void)

Complete the Unicode input sequence. The exact behavior depends on the currently selected input mode:

  • macOS: Release UNICODE_KEY_MAC
  • Linux: Tap Space
  • WinCompose: Tap Enter
  • HexNumpad: Release Left Alt
  • Emacs: Tap Enter

This function is weakly defined, and can be overridden in user code.


void unicode_input_cancel(void)

Cancel the Unicode input sequence. The exact behavior depends on the currently selected input mode:

  • macOS: Release UNICODE_KEY_MAC
  • Linux: Tap Escape
  • WinCompose: Tap Escape
  • HexNumpad: Release Left Alt
  • Emacs: Tap Ctrl+G

This function is weakly defined, and can be overridden in user code.


void register_unicode(uint32_t code_point)

Input a single Unicode character. A surrogate pair will be sent if required by the input mode.

Arguments

  • uint32_t code_point
    The code point of the character to send.

void send_unicode_string(const char *str)

Send a string containing Unicode characters.

Arguments

  • const char *str
    The string to send.

uint8_t unicodemap_index(uint16_t keycode)

Get the index into the unicode_map array for the given keycode, respecting shift state for pair keycodes.

Arguments

  • uint16_t keycode
    The Unicode Map keycode to get the index of.

Return Value

An index into the unicode_map array.


uint32_t unicodemap_get_code_point(uint8_t index)

Get the code point for the given index in the unicode_map array.

Arguments

  • uint8_t index
    The index into the unicode_map array.

Return Value

A Unicode code point value.


void register_unicodemap(uint8_t index)

Send the code point for the given index in the unicode_map array.

Arguments

  • uint8_t index
    The index into the unicode_map array.

void ucis_start(void)

Begin the input sequence.


bool ucis_active(void)

Whether UCIS is currently active.

Return Value

true if UCIS is active.


uint8_t ucis_count(void)

Get the number of characters in the input sequence buffer.

Return Value

The current input sequence buffer length.


bool ucis_add(uint16_t keycode)

Add the given keycode to the input sequence buffer.

Arguments

  • uint16_t keycode
    The keycode to add. Must be between KC_A and KC_Z, or KC_1 and KC_0.

Return Value

true if the keycode was added.


bool ucis_remove_last(void)

Remove the last character from the input sequence buffer.

Return Value

true if the sequence was not empty.


void ucis_finish(void)

Mark the input sequence as complete, and attempt to match.


void ucis_cancel(void)

Cancel the input sequence.


void register_ucis(void)

Send the code point(s) for the given UCIS index.

Arguments

  • uint8_t index
    The index into the UCIS symbol table.