mirror of
https://github.com/mfulz/qmk_firmware.git
synced 2025-11-03 23:02:34 +01:00
183 lines
11 KiB
Markdown
183 lines
11 KiB
Markdown
# Modifier Keys :id=modifier-keys
|
|
|
|
These allow you to combine a modifier with a keycode. When pressed, the keydown event for the modifier, then `kc` will be sent. On release, the keyup event for `kc`, then the modifier will be sent.
|
|
|
|
|Key |Aliases |Description |
|
|
|----------|----------------------------------|------------------------------------------------------|
|
|
|`LCTL(kc)`|`C(kc)` |Hold Left Control and press `kc` |
|
|
|`LSFT(kc)`|`S(kc)` |Hold Left Shift and press `kc` |
|
|
|`LALT(kc)`|`A(kc)`, `LOPT(kc)` |Hold Left Alt and press `kc` |
|
|
|`LGUI(kc)`|`G(kc)`, `LCMD(kc)`, `LWIN(kc)` |Hold Left GUI and press `kc` |
|
|
|`RCTL(kc)`| |Hold Right Control and press `kc` |
|
|
|`RSFT(kc)`| |Hold Right Shift and press `kc` |
|
|
|`RALT(kc)`|`ROPT(kc)`, `ALGR(kc)` |Hold Right Alt and press `kc` |
|
|
|`RGUI(kc)`|`RCMD(kc)`, `LWIN(kc)` |Hold Right GUI and press `kc` |
|
|
|`LSG(kc)` |`SGUI(kc)`, `SCMD(kc)`, `SWIN(kc)`|Hold Left Shift and GUI and press `kc` |
|
|
|`LAG(kc)` | |Hold Left Alt and Left GUI and press `kc` |
|
|
|`RSG(kc)` | |Hold Right Shift and Right GUI and press `kc` |
|
|
|`RAG(kc)` | |Hold Right Alt and Right GUI and press `kc` |
|
|
|`LCA(kc)` | |Hold Left Control and Alt and press `kc` |
|
|
|`LSA(kc)` | |Hold Left Shift and Left Alt and press `kc` |
|
|
|`RSA(kc)` |`SAGR(kc)` |Hold Right Shift and Right Alt (AltGr) and press `kc` |
|
|
|`RCS(kc)` | |Hold Right Control and Right Shift and press `kc` |
|
|
|`LCAG(kc)`| |Hold Left Control, Alt and GUI and press `kc` |
|
|
|`MEH(kc)` | |Hold Left Control, Shift and Alt and press `kc` |
|
|
|`HYPR(kc)`| |Hold Left Control, Shift, Alt and GUI and press `kc` |
|
|
|
|
You can also chain them, for example `LCTL(LALT(KC_DEL))` or `C(A(KC_DEL))` makes a key that sends Control+Alt+Delete with a single keypress.
|
|
|
|
# Checking Modifier State :id=checking-modifier-state
|
|
|
|
The current modifier state can mainly be accessed with two functions: `get_mods()` for normal modifiers and modtaps and `get_oneshot_mods()` for one-shot modifiers (unless they're held, in which case they act like normal modifier keys).
|
|
|
|
The presence of one or more specific modifiers in the current modifier state can be detected by ANDing the modifier state with a mod mask corresponding to the set of modifiers you want to match for. The reason why bitwise operators are used is that the modifier state is stored as a single byte in the format (GASC)<sub>R</sub>(GASC)<sub>L</sub>.
|
|
|
|
Thus, to give an example, `01000010` would be the internal representation of LShift+RAlt.
|
|
For more information on bitwise operators in C, click [here](https://en.wikipedia.org/wiki/Bitwise_operations_in_C) to open the Wikipedia page on the topic.
|
|
|
|
In practice, this means that you can check whether a given modifier is active with `get_mods() & MOD_BIT(KC_<modifier>)` (see the [list of modifier keycodes](keycodes_basic.md#modifiers)) or with `get_mods() & MOD_MASK_<modifier>` if the difference between left and right hand modifiers is not important and you want to match both. Same thing can be done for one-shot modifiers if you replace `get_mods()` with `get_oneshot_mods()`.
|
|
|
|
To check that *only* a specific set of mods is active at a time, AND the modifier state and your desired mod mask as explained above and compare the result to the mod mask itself: `get_mods() & <mod mask> == <mod mask>`.
|
|
|
|
For example, let's say you want to trigger a piece of custom code if one-shot left control and one-shot left shift are on but every other one-shot mods are off. To do so, you can compose the desired mod mask by combining the mod bits for left control and shift with `(MOD_BIT(KC_LCTL) | MOD_BIT(KC_LSFT))` and then plug it in: `get_oneshot_mods() & (MOD_BIT(KC_LCTL) | MOD_BIT(KC_LSFT)) == (MOD_BIT(KC_LCTL) | MOD_BIT(KC_LSFT))`. Using `MOD_MASK_CS` instead for the mod bitmask would have forced you to press four modifier keys (both versions of control and shift) to fulfill the condition.
|
|
|
|
The full list of mod masks is as follows:
|
|
|
|
| Mod Mask Name | Matching Modifiers |
|
|
|--------------------|------------------------------------------------|
|
|
| `MOD_MASK_CTRL` | LCTRL , RCTRL |
|
|
| `MOD_MASK_SHIFT` | LSHIFT , RSHIFT |
|
|
| `MOD_MASK_ALT` | LALT , RALT |
|
|
| `MOD_MASK_GUI` | LGUI , RGUI |
|
|
| `MOD_MASK_CS` | CTRL , SHIFT |
|
|
| `MOD_MASK_CA` | (L/R)CTRL , (L/R)ALT |
|
|
| `MOD_MASK_CG` | (L/R)CTRL , (L/R)GUI |
|
|
| `MOD_MASK_SA` | (L/R)SHIFT , (L/R)ALT |
|
|
| `MOD_MASK_SG` | (L/R)SHIFT , (L/R)GUI |
|
|
| `MOD_MASK_AG` | (L/R)ALT , (L/R)GUI |
|
|
| `MOD_MASK_CSA` | (L/R)CTRL , (L/R)SHIFT , (L/R)ALT |
|
|
| `MOD_MASK_CSG` | (L/R)CTRL , (L/R)SHIFT , (L/R)GUI |
|
|
| `MOD_MASK_CAG` | (L/R)CTRL , (L/R)ALT , (L/R)GUI |
|
|
| `MOD_MASK_SAG` | (L/R)SHIFT , (L/R)ALT , (L/R)GUI |
|
|
| `MOD_MASK_CSAG` | (L/R)CTRL , (L/R)SHIFT , (L/R)ALT , (L/R)GUI |
|
|
|
|
Aside from accessing the currently active modifiers using `get_mods()`, there exists some other functions you can use to modify the modifier state, where the `mods` argument refers to the modifiers bitmask.
|
|
|
|
* `add_mods(mods)`: Enable `mods` without affecting any other modifiers
|
|
* `register_mods(mods)`: Like `add_mods` but send a keyboard report immediately.
|
|
* `del_mods(mods)`: Disable `mods` without affecting any other modifiers
|
|
* `unregister_mods(mods)`: Like `del_mods` but send a keyboard report immediately.
|
|
* `set_mods(mods)`: Overwrite current modifier state with `mods`
|
|
* `clear_mods()`: Reset the modifier state by disabling all modifiers
|
|
|
|
Similarly, in addition to `get_oneshot_mods()`, there also exists these functions for one-shot mods:
|
|
|
|
* `add_oneshot_mods(mods)`: Enable `mods` without affecting any other one-shot modifiers
|
|
* `del_oneshot_mods(mods)`: Disable `mods` without affecting any other one-shot modifiers
|
|
* `set_oneshot_mods(mods)`: Overwrite current one-shot modifier state with `mods`
|
|
* `clear_oneshot_mods()`: Reset the one-shot modifier state by disabling all one-shot modifiers
|
|
|
|
## Examples :id=examples
|
|
|
|
The following examples use [advanced macro functions](feature_macros.md#advanced-macro-functions) which you can read more about in the [documentation page on macros](feature_macros.md).
|
|
|
|
### Alt + Escape for Alt + Tab :id=alt-escape-for-alt-tab
|
|
|
|
Simple example where chording Left Alt with `KC_ESC` makes it behave like `KC_TAB` for alt-tabbing between applications. This example strictly checks if only Left Alt is active, meaning you can't do Alt+Shift+Esc to switch between applications in reverse order. Also keep in mind that this removes the ability to trigger the actual Alt+Escape keyboard shortcut, though it keeps the ability to do AltGr+Escape.
|
|
|
|
```c
|
|
bool process_record_user(uint16_t keycode, keyrecord_t *record) {
|
|
switch (keycode) {
|
|
|
|
case KC_ESC:
|
|
// Detect the activation of only Left Alt
|
|
if ((get_mods() & MOD_BIT(KC_LALT)) == MOD_BIT(KC_LALT)) {
|
|
if (record->event.pressed) {
|
|
// No need to register KC_LALT because it's already active.
|
|
// The Alt modifier will apply on this KC_TAB.
|
|
register_code(KC_TAB);
|
|
} else {
|
|
unregister_code(KC_TAB);
|
|
}
|
|
// Do not let QMK process the keycode further
|
|
return false;
|
|
}
|
|
// Else, let QMK process the KC_ESC keycode as usual
|
|
return true;
|
|
|
|
}
|
|
return true;
|
|
};
|
|
```
|
|
|
|
### Shift + Backspace for Delete :id=shift-backspace-for-delete
|
|
|
|
Advanced example where the original behaviour of shift is cancelled when chorded with `KC_BSPC` and is instead fully replaced by `KC_DEL`. Two main variables are created to make this work well: `mod_state` and `delkey_registered`. The first one stores the modifier state and is used to restore it after registering `KC_DEL`. The second variable is a boolean variable (true or false) which keeps track of the status of `KC_DEL` to manage the release of the whole Backspace/Delete key correctly.
|
|
|
|
As opposed to the previous example, this doesn't use strict modifier checking. Pressing `KC_BSPC` while one or two shifts are active is enough to trigger this custom code, regardless of the state of other modifiers. That approach offers some perks: Ctrl+Shift+Backspace lets us delete the next word (Ctrl+Delete) and Ctrl+Alt+Shift+Backspace lets us execute the Ctrl+Alt+Del keyboard shortcut.
|
|
|
|
```c
|
|
// Initialize variable holding the binary
|
|
// representation of active modifiers.
|
|
uint8_t mod_state;
|
|
bool process_record_user(uint16_t keycode, keyrecord_t *record) {
|
|
// Store the current modifier state in the variable for later reference
|
|
mod_state = get_mods();
|
|
switch (keycode) {
|
|
|
|
case KC_BSPC:
|
|
{
|
|
// Initialize a boolean variable that keeps track
|
|
// of the delete key status: registered or not?
|
|
static bool delkey_registered;
|
|
if (record->event.pressed) {
|
|
// Detect the activation of either shift keys
|
|
if (mod_state & MOD_MASK_SHIFT) {
|
|
// First temporarily canceling both shifts so that
|
|
// shift isn't applied to the KC_DEL keycode
|
|
del_mods(MOD_MASK_SHIFT);
|
|
register_code(KC_DEL);
|
|
// Update the boolean variable to reflect the status of KC_DEL
|
|
delkey_registered = true;
|
|
// Reapplying modifier state so that the held shift key(s)
|
|
// still work even after having tapped the Backspace/Delete key.
|
|
set_mods(mod_state);
|
|
return false;
|
|
}
|
|
} else { // on release of KC_BSPC
|
|
// In case KC_DEL is still being sent even after the release of KC_BSPC
|
|
if (delkey_registered) {
|
|
unregister_code(KC_DEL);
|
|
delkey_registered = false;
|
|
return false;
|
|
}
|
|
}
|
|
// Let QMK process the KC_BSPC keycode as usual outside of shift
|
|
return true;
|
|
}
|
|
|
|
}
|
|
return true;
|
|
};
|
|
```
|
|
|
|
# Legacy Content :id=legacy-content
|
|
|
|
This page used to encompass a large set of features. We have moved many sections that used to be part of this page to their own pages. Everything below this point is simply a redirect so that people following old links on the web find what they're looking for.
|
|
|
|
## Layers :id=switching-and-toggling-layers
|
|
|
|
* [Layers](feature_layers.md)
|
|
|
|
## Mod-Tap :id=mod-tap
|
|
|
|
* [Mod-Tap](mod_tap.md)
|
|
|
|
## One Shot Keys :id=one-shot-keys
|
|
|
|
* [One Shot Keys](one_shot_keys.md)
|
|
|
|
## Tap-Hold Configuration Options :id=tap-hold-configuration-options
|
|
|
|
* [Tap-Hold Configuration Options](tap_hold.md)
|