qmk/modules/getreuer/tap_flow/tap_flow.h

124 lines
4.1 KiB
C

// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**
* @file tap_flow.h
* @brief Tap Flow module: disable HRMs during fast typing
*
* This module is an implementation of "global quick tap" (GQT), aka "require
* prior idle," for tap-hold keys. It is particularly useful for home row mods
* to avoid accidental mod triggers in fast typing.
*
* Tap Flow modifies the tap-hold decision such that when a tap-hold key is
* pressed within a short timeout of the preceding key, the tapping function is
* used. The assumption is that during fast typing, only the tap function of
* tap-hold keys is desired (though perhaps with an exception for Shift or
* AltGr, noted below), whereas the hold functions (mods and layers) are
* used in isolation, or at least with a brief pause preceding the tap-hold key
* press.
*
* Optionally, the feature can be customized with the `get_tap_flow()` callback.
* In this way, exceptions may be made for Shift and AltGr (or whatever you
* wish) to use a shorter time or to disable filtering for those keys entirely.
*
*
* For full documentation, see
* <https://getreuer.info/posts/keyboards/tap-flow>
*/
#pragma once
#include "quantum.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifndef TAP_FLOW_TERM
# define TAP_FLOW_TERM 150
#endif // TAP_FLOW_TERM
/**
* Optional callback to customize where Tap Flow is enabled.
*
* Tap Flow is constrained to certain keys by the following rule: this callback
* is called for both the tap-hold key *and* the key press immediately preceding
* it. If the callback returns true for both keycodes, Tap Flow may apply.
*
* The default implementation of this callback corresponds to
*
* bool is_tap_flow_key(uint16_t keycode) {
* switch (keycode) {
* case QK_MOD_TAP ... QK_MOD_TAP_MAX:
* keycode = QK_MOD_TAP_GET_TAP_KEYCODE(keycode);
* break;
* case QK_LAYER_TAP ... QK_LAYER_TAP_MAX:
* keycode = QK_LAYER_TAP_GET_TAP_KEYCODE(keycode);
* break;
* }
* switch (keycode) {
* case KC_SPC:
* case KC_A ... KC_Z:
* case KC_DOT:
* case KC_COMM:
* case KC_SCLN:
* case KC_SLSH:
* return true;
* }
* return false;
* }
*
* @param keycode Keycode of the key.
* @return Whether to enable Tap Flow for this key.
*/
bool is_tap_flow_key(uint16_t keycode);
/**
* Optional callback to customize filtering.
*
* Tap Flow acts only when key events are closer together than this time.
*
* Return a time of 0 to disable filtering. In this way, Tap Flow may be
* disabled for certain tap-hold keys, or when following certain previous keys.
*
* The default implementation of this callback is
*
* uint16_t get_tap_flow_term(uint16_t keycode, keyrecord_t* record,
* uint16_t prev_keycode) {
* if (is_tap_flow_key(keycode) && is_tap_flow_key(prev_keycode)) {
* return g_tap_flow_term;
* }
* return 0;
* }
*
* NOTE: If both `is_tap_flow_key()` and `get_tap_flow_term()` are defined, then
* `get_tap_flow_term()` takes precedence.
*
* @param keycode Keycode of the tap-hold key.
* @param record keyrecord_t of the tap-hold event.
* @param prev_keycode Keycode of the previously pressed key.
* @return Timeout in milliseconds.
*/
uint16_t get_tap_flow_term(uint16_t keycode, keyrecord_t* record,
uint16_t prev_keycode);
/** @deprecated Use `get_tap_flow_term()` instead. */
uint16_t get_tap_flow(uint16_t keycode, keyrecord_t* record,
uint16_t prev_keycode);
extern uint16_t g_tap_flow_term;
#ifdef __cplusplus
}
#endif