From 3993b15f054265071730cdb450f43457dcf4c64a Mon Sep 17 00:00:00 2001 From: Pascal Getreuer <50221757+getreuer@users.noreply.github.com> Date: Sat, 20 May 2023 05:35:06 -0700 Subject: [Core] Add Repeat Key ("repeat last key") as a core feature. (#19700) Co-authored-by: casuanoob <96005765+casuanoob@users.noreply.github.com> Co-authored-by: Sergey Vlasov --- docs/feature_repeat_key.md | 457 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 457 insertions(+) create mode 100644 docs/feature_repeat_key.md (limited to 'docs/feature_repeat_key.md') diff --git a/docs/feature_repeat_key.md b/docs/feature_repeat_key.md new file mode 100644 index 0000000000..6fa8a724ef --- /dev/null +++ b/docs/feature_repeat_key.md @@ -0,0 +1,457 @@ +# Repeat Key + +The Repeat Key performs the action of the last pressed key. Tapping the Repeat +Key after tapping the Z key types another "`z`." This is useful for +typing doubled letters, like the `z` in "`dazzle`": a double tap on Z +can instead be a roll from Z to Repeat, which is +potentially faster and more comfortable. The Repeat Key is also useful for +hotkeys, like repeating Ctrl + Shift + Right Arrow to select by word. + +Repeat Key remembers mods that were active with the last key press. These mods +are combined with any additional mods while pressing the Repeat Key. If the last +press key was Ctrl + Z, then Shift + +Repeat performs Ctrl + Shift + `Z`. + +## How do I enable Repeat Key + +In your `rules.mk`, add: + +```make +REPEAT_KEY_ENABLE = yes +``` + +Then pick a key in your keymap and assign it the keycode `QK_REPEAT_KEY` (short +alias `QK_REP`). Optionally, use the keycode `QK_ALT_REPEAT_KEY` (short alias +`QK_AREP`) on another key. + +## Keycodes + +|Keycode |Aliases |Description | +|-----------------------|---------|-------------------------------------| +|`QK_REPEAT_KEY` |`QK_REP` |Repeat the last pressed key | +|`QK_ALT_REPEAT_KEY` |`QK_AREP`|Perform alternate of the last key | + +## Alternate Repeating + +The Alternate Repeat Key performs the "alternate" action of the last pressed key +if it is defined. By default, Alternate Repeat is defined for navigation keys to +act in the reverse direction. When the last key is the common "select by word" +hotkey Ctrl + Shift + Right Arrow, the Alternate Repeat Key performs Ctrl + +Shift + Left Arrow, which together with the Repeat Key enables convenient +selection by words in either direction. + +Alternate Repeat is enabled with the Repeat Key by default. Optionally, to +reduce firmware size, Alternate Repeat may be disabled by adding in config.h: + +```c +#define NO_ALT_REPEAT_KEY +``` + +The following alternate keys are defined by default. See +`get_alt_repeat_key_keycode_user()` below for how to change or add to these +definitions. Where it makes sense, these definitions also include combinations +with mods, like Ctrl + Left ↔ Ctrl + Right Arrow. + +**Navigation** + +|Keycodes |Description | +|-----------------------------------|-----------------------------------| +|`KC_LEFT` ↔ `KC_RGHT` | Left ↔ Right Arrow | +|`KC_UP` ↔ `KC_DOWN` | Up ↔ Down Arrow | +|`KC_HOME` ↔ `KC_END` | Home ↔ End | +|`KC_PGUP` ↔ `KC_PGDN` | Page Up ↔ Page Down | +|`KC_MS_L` ↔ `KC_MS_R` | Mouse Cursor Left ↔ Right | +|`KC_MS_U` ↔ `KC_MS_D` | Mouse Cursor Up ↔ Down | +|`KC_WH_L` ↔ `KC_WH_R` | Mouse Wheel Left ↔ Right | +|`KC_WH_U` ↔ `KC_WH_D` | Mouse Wheel Up ↔ Down | + +**Misc** + +|Keycodes |Description | +|-----------------------------------|-----------------------------------| +|`KC_BSPC` ↔ `KC_DEL` | Backspace ↔ Delete | +|`KC_LBRC` ↔ `KC_RBRC` | `[` ↔ `]` | +|`KC_LCBR` ↔ `KC_RCBR` | `{` ↔ `}` | + +**Media** + +|Keycodes |Description | +|-----------------------------------|-----------------------------------| +|`KC_WBAK` ↔ `KC_WFWD` | Browser Back ↔ Forward | +|`KC_MNXT` ↔ `KC_MPRV` | Next ↔ Previous Media Track | +|`KC_MFFD` ↔ `KC_MRWD` | Fast Forward ↔ Rewind Media | +|`KC_VOLU` ↔ `KC_VOLD` | Volume Up ↔ Down | +|`KC_BRIU` ↔ `KC_BRID` | Brightness Up ↔ Down | + +**Hotkeys in Vim, Emacs, and other programs** + +|Keycodes |Description | +|-----------------------------------|-----------------------------------| +|mod + `KC_F` ↔ mod + `KC_B` | Forward ↔ Backward | +|mod + `KC_D` ↔ mod + `KC_U` | Down ↔ Up | +|mod + `KC_N` ↔ mod + `KC_P` | Next ↔ Previous | +|mod + `KC_A` ↔ mod + `KC_E` | Home ↔ End | +|mod + `KC_O` ↔ mod + `KC_I` | Vim jump list Older ↔ Newer | +|`KC_J` ↔ `KC_K` | Down ↔ Up | +|`KC_H` ↔ `KC_L` | Left ↔ Right | +|`KC_W` ↔ `KC_B` | Forward ↔ Backward by Word | + +(where above, "mod" is Ctrl, Alt, or GUI) + + +## Defining alternate keys + +Use the `get_alt_repeat_key_keycode_user()` callback to define the "alternate" +for additional keys or override the default definitions. For example, to define +Ctrl + Y as the alternate of Ctrl + Z, and vice versa, add the following in +keymap.c: + +```c +uint16_t get_alt_repeat_key_keycode_user(uint16_t keycode, uint8_t mods) { + if ((mods & MOD_MASK_CTRL)) { // Was Ctrl held? + switch (keycode) { + case KC_Y: return C(KC_Z); // Ctrl + Y reverses to Ctrl + Z. + case KC_Z: return C(KC_Y); // Ctrl + Z reverses to Ctrl + Y. + } + } + + return KC_TRNS; // Defer to default definitions. +} +``` + +The `keycode` and `mods` args are the keycode and mods that were active with the +last pressed key. The meaning of the return value from this function is: + +* `KC_NO` – do nothing (any predefined alternate key is not used); +* `KC_TRNS` – use the default alternate key if it exists; +* anything else – use the specified keycode. Any keycode may be returned + as an alternate key, including custom keycodes. + +Another example, defining Shift + Tab as the alternate of Tab, and vice versa: + +```c +uint16_t get_alt_repeat_key_keycode_user(uint16_t keycode, uint8_t mods) { + bool shifted = (mods & MOD_MASK_SHIFT); // Was Shift held? + switch (keycode) { + case KC_TAB: + if (shifted) { // If the last key was Shift + Tab, + return KC_TAB; // ... the reverse is Tab. + } else { // Otherwise, the last key was Tab, + return S(KC_TAB); // ... and the reverse is Shift + Tab. + } + } + + return KC_TRNS; +} +``` + +#### Eliminating SFBs + +Alternate Repeat can be configured more generally to perform an action that +"complements" the last key. Alternate Repeat is not limited to reverse +repeating, and it need not be symmetric. You can use it to eliminate cases of +same-finger bigrams in your layout, that is, pairs of letters typed by the same +finger. The following addresses the top 5 same-finger bigrams in English on +QWERTY, so that for instance "`ed`" may be typed as E, Alt +Repeat. + +```c +uint16_t get_alt_repeat_key_keycode_user(uint16_t keycode, uint8_t mods) { + switch (keycode) { + case KC_E: return KC_D; // For "ED" bigram. + case KC_D: return KC_E; // For "DE" bigram. + case KC_C: return KC_E; // For "CE" bigram. + case KC_L: return KC_O; // For "LO" bigram. + case KC_U: return KC_N; // For "UN" bigram. + } + + return KC_TRNS; +} +``` + +#### Typing shortcuts + +A useful possibility is having Alternate Repeat press [a +macro](feature_macros.md). This way macros can be used without having to +dedicate keys to them. The following defines a couple shortcuts. + +* Typing K, Alt Repeat produces "`keyboard`," with the + initial "`k`" typed as usual and the "`eybord`" produced by the macro. +* Typing ., Alt Repeat produces "`../`," handy for "up + directory" on the shell. Similary, . types the initial "`.`" and + "`./`" is produced by the macro. + +```c +enum custom_keycodes { + M_KEYBOARD = SAFE_RANGE, + M_UPDIR, + // Other custom keys... +}; + +uint16_t get_alt_repeat_key_keycode_user(uint16_t keycode, uint8_t mods) { + switch (keycode) { + case KC_K: return M_KEYBOARD; + case KC_DOT: return M_UPDIR; + } + + return KC_TRNS; +} + +bool process_record_user(uint16_t keycode, keyrecord_t* record) { + switch (keycode) { + case M_KEYBOARD: SEND_STRING(/*k*/"eyboard"); break; + case M_UPDIR: SEND_STRING(/*.*/"./"); break; + } + return true; +} +``` + +## Ignoring certain keys and mods + +In tracking what is "the last key" to be repeated or alternate repeated, +modifier and layer switch keys are always ignored. This makes it possible to set +some mods and change layers between pressing a key and repeating it. By default, +all other (non-modifier, non-layer switch) keys are remembered so that they are +eligible for repeating. To configure additional keys to be ignored, define +`remember_last_key_user()` in your keymap.c. + +#### Ignoring a key + +The following ignores the Backspace key: + +```c +bool remember_last_key_user(uint16_t keycode, keyrecord_t* record, + uint8_t* remembered_mods) { + switch (keycode) { + case KC_BSPC: + return false; // Ignore backspace. + } + + return true; // Other keys can be repeated. +} +``` + +Then for instance, the Repeat key in Left Arrow, +Backspace, Repeat sends Left Arrow again instead of +repeating Backspace. + +The `remember_last_key_user()` callback is called on every key press excluding +modifiers and layer switches. Returning true indicates the key is remembered, +while false means it is ignored. + +#### Filtering remembered mods + +The `remembered_mods` arg represents the mods that will be remembered with +this key. It can be modified to forget certain mods. This may be +useful to forget capitalization when repeating shifted letters, so that "Aaron" +does not becom "AAron": + +```c +bool remember_last_key_user(uint16_t keycode, keyrecord_t* record, + uint8_t* remembered_mods) { + // Forget Shift on letter keys when Shift or AltGr are the only mods. + switch (keycode) { + case KC_A ... KC_Z: + if ((*remembered_mods & ~(MOD_MASK_SHIFT | MOD_BIT(KC_RALT))) == 0) { + *remembered_mods &= ~MOD_MASK_SHIFT; + } + break; + } + + return true; +} +``` + +#### Further conditions + +Besides checking the keycode, this callback could also make conditions based on +the current layer state (with `IS_LAYER_ON(layer)`) or mods (`get_mods()`). For +example, the following ignores keys on layer 2 as well as key combinations +involving GUI: + +```c +bool remember_last_key_user(uint16_t keycode, keyrecord_t* record, + uint8_t* remembered_mods) { + if (IS_LAYER_ON(2) || (get_mods() & MOD_MASK_GUI)) { + return false; // Ignore layer 2 keys and GUI chords. + } + + return true; // Other keys can be repeated. +} +``` + +?> See [Layer Functions](feature_layers.md#functions) and [Checking Modifier +State](feature_advanced_keycodes.md#checking-modifier-state) for further +details. + + +## Handle how a key is repeated + +By default, pressing the Repeat Key will simply behave as if the last key +were pressed again. This also works with macro keys with custom handlers, +invoking the macro again. In case fine-tuning is needed for sensible repetition, +you can handle how a key is repeated with `get_repeat_key_count()` within +`process_record_user()`. + +The `get_repeat_key_count()` function returns a signed count of times the key +has been repeated or alternate repeated. When a key is pressed as usual, +`get_repeat_key_count()` is 0. On the first repeat, it is 1, then the second +repeat, 2, and so on. Negative counts are used similarly for alternate +repeating. For instance supposing `MY_MACRO` is a custom keycode used in the +layout: + +```c +bool process_record_user(uint16_t keycode, keyrecord_t* record) { + switch (keycode) { + case MY_MACRO: + if (get_repeat_key_count() > 0) { + // MY_MACRO is being repeated! + if (record->event.pressed) { + SEND_STRING("repeat!"); + } + } else { + // MY_MACRO is being used normally. + if (record->event.pressed) { + SEND_STRING("macro"); + } + } + return false; + + // Other macros... + } + return true; +} +``` + +## Handle how a key is alternate repeated + +Pressing the Alternate Repeat Key behaves as if the "alternate" of the last +pressed key were pressed, if an alternate is defined. To define how a particular +key is alternate repeated, use the `get_alt_repeat_key_keycode_user()` callback +as described above to define which keycode to use as its alternate. Beyond this, +`get_repeat_key_count()` may be used in custom handlers to fine-tune behavior +when alternate repeating. + +The following example defines `MY_MACRO` as its own alternate, and specially +handles repeating and alternate repeating: + +```c +uint16_t get_alt_repeat_key_keycode_user(uint16_t keycode, uint8_t mods) { + switch (keycode) { + case MY_MACRO: return MY_MACRO; // MY_MACRO is its own alternate. + } + return KC_TRNS; +} + +bool process_record_user(uint16_t keycode, keyrecord_t* record) { + switch (keycode) { + case MY_MACRO: + if (get_repeat_key_count() > 0) { // Repeating. + if (record->event.pressed) { + SEND_STRING("repeat!"); + } + } else if (get_repeat_key_count() < 0) { // Alternate repeating. + if (record->event.pressed) { + SEND_STRING("alt repeat!"); + } + } else { // Used normally. + if (record->event.pressed) { + SEND_STRING("macro"); + } + } + return false; + + // Other macros... + } + return true; +} +``` + + +## Functions + +| Function | Description | +|--------------------------------|------------------------------------------------------------------------| +| `get_last_keycode()` | The last key's keycode, the key to be repeated. | +| `get_last_mods()` | Mods to apply when repeating. | +| `set_last_keycode(kc)` | Set the keycode to be repeated. | +| `set_last_mods(mods)` | Set the mods to apply when repeating. | +| `get_repeat_key_count()` | Signed count of times the key has been repeated or alternate repeated. | +| `get_alt_repeat_key_keycode()` | Keycode to be used for alternate repeating. | + + +## Additional "Alternate" keys + +By leveraging `get_last_keycode()` in macros, it is possible to define +additional, distinct "Alternate Repeat"-like keys. The following defines two +keys `ALTREP2` and `ALTREP3` and implements ten shortcuts with them for common +English 5-gram letter patterns, taking inspiration from +[Stenotype](feature_stenography.md): + + +| Typing | Produces | Typing | Produces | +|----------------------------------|----------|----------------------------------|----------| +| A, ALTREP2 | `ation` | A, ALTREP3 | `about` | +| I, ALTREP2 | `ition` | I, ALTREP3 | `inter` | +| S, ALTREP2 | `ssion` | S, ALTREP3 | `state` | +| T, ALTREP2 | `their` | T, ALTREP3 | `there` | +| W, ALTREP2 | `which` | W, ALTREP3 | `would` | + +```c +enum custom_keycodes { + ALTREP2 = SAFE_RANGE, + ALTREP3, +}; + +// Use ALTREP2 and ALTREP3 in your layout... + +bool remember_last_key_user(uint16_t keycode, keyrecord_t* record, + uint8_t* remembered_mods) { + switch (keycode) { + case ALTREP2: + case ALTREP3: + return false; // Ignore ALTREP keys. + } + + return true; // Other keys can be repeated. +} + +static void process_altrep2(uint16_t keycode, uint8_t mods) { + switch (keycode) { + case KC_A: SEND_STRING(/*a*/"tion"); break; + case KC_I: SEND_STRING(/*i*/"tion"); break; + case KC_S: SEND_STRING(/*s*/"sion"); break; + case KC_T: SEND_STRING(/*t*/"heir"); break; + case KC_W: SEND_STRING(/*w*/"hich"); break; + } +} + +static void process_altrep3(uint16_t keycode, uint8_t mods) { + switch (keycode) { + case KC_A: SEND_STRING(/*a*/"bout"); break; + case KC_I: SEND_STRING(/*i*/"nter"); break; + case KC_S: SEND_STRING(/*s*/"tate"); break; + case KC_T: SEND_STRING(/*t*/"here"); break; + case KC_W: SEND_STRING(/*w*/"ould"); break; + } +} + +bool process_record_user(uint16_t keycode, keyrecord_t* record) { + switch (keycode) { + case ALTREP2: + if (record->event.pressed) { + process_altrep2(get_last_keycode(), get_last_mods()); + } + return false; + + case ALTREP3: + if (record->event.pressed) { + process_altrep3(get_last_keycode(), get_last_mods()); + } + return false; + } + + return true; +} +``` + -- cgit v1.2.3