diff options
Diffstat (limited to 'quantum/pointing_device_gestures.c')
| -rw-r--r-- | quantum/pointing_device_gestures.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/quantum/pointing_device_gestures.c b/quantum/pointing_device_gestures.c new file mode 100644 index 0000000000..02b11ebe3f --- /dev/null +++ b/quantum/pointing_device_gestures.c @@ -0,0 +1,133 @@ +/* Copyright 2022 Daniel Kao <daniel.m.kao@gmail.com> + * + * 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 <string.h> +#include "pointing_device_gestures.h" +#include "timer.h" + +#ifdef POINTING_DEVICE_GESTURES_CURSOR_GLIDE_ENABLE +# ifdef POINTING_DEVICE_MOTION_PIN +# error POINTING_DEVICE_MOTION_PIN not supported when using inertial cursor. Need repeated calls to get_report() to generate glide events. +# endif + +static void cursor_glide_stop(cursor_glide_context_t* glide) { + memset(&glide->status, 0, sizeof(glide->status)); +} + +static cursor_glide_t cursor_glide(cursor_glide_context_t* glide) { + cursor_glide_status_t* status = &glide->status; + cursor_glide_t report; + int32_t p; + int32_t x, y; + + if (status->v0 == 0) { + report.dx = 0; + report.dy = 0; + report.valid = false; + cursor_glide_stop(glide); + goto exit; + } + + status->counter++; + /* Calculate current 1D position */ + p = status->v0 * status->counter - (int32_t)glide->config.coef * status->counter * status->counter / 2; + /* + * Translate to x & y axes + * Done this way instead of applying friction to each axis separately, so we don't end up with the shorter axis stuck at 0 towards the end of diagonal movements. + */ + x = (int32_t)(p * status->dx0 / status->v0); + y = (int32_t)(p * status->dy0 / status->v0); + report.dx = (mouse_xy_report_t)(x - status->x); + report.dy = (mouse_xy_report_t)(y - status->y); + report.valid = true; + if (report.dx <= 1 && report.dx >= -1 && report.dy <= 1 && report.dy >= -1) { + /* Stop gliding once speed is low enough */ + cursor_glide_stop(glide); + goto exit; + } + status->x = x; + status->y = y; + status->timer = timer_read(); + +exit: + return report; +} + +cursor_glide_t cursor_glide_check(cursor_glide_context_t* glide) { + cursor_glide_t invalid_report = {0, 0, false}; + cursor_glide_status_t* status = &glide->status; + + if (status->z || (status->dx0 == 0 && status->dy0 == 0) || timer_elapsed(status->timer) < glide->config.interval) { + return invalid_report; + } else { + return cursor_glide(glide); + } +} + +static inline uint16_t sqrt32(uint32_t x) { + uint32_t l, m, h; + + if (x == 0) { + return 0; + } else if (x > (UINT16_MAX >> 2)) { + /* Safe upper bound to avoid integer overflow with m * m */ + h = UINT16_MAX; + } else { + /* Upper bound based on closest log2 */ + h = (1 << (((__builtin_clzl(1) - __builtin_clzl(x) + 1) + 1) >> 1)); + } + /* Lower bound based on closest log2 */ + l = (1 << ((__builtin_clzl(1) - __builtin_clzl(x)) >> 1)); + + /* Binary search to find integer square root */ + while (l != h - 1) { + m = (l + h) / 2; + if (m * m <= x) { + l = m; + } else { + h = m; + } + } + return l; +} + +cursor_glide_t cursor_glide_start(cursor_glide_context_t* glide) { + cursor_glide_t invalid_report = {0, 0, false}; + cursor_glide_status_t* status = &glide->status; + + status->timer = timer_read(); + status->counter = 0; + status->v0 = (status->dx0 == 0 && status->dy0 == 0) ? 0.0 : sqrt32(((int32_t)status->dx0 * 256 * status->dx0 * 256) + ((int32_t)status->dy0 * 256 * status->dy0 * 256)); // skip trigonometry if not needed, calculate distance in Q8 + status->x = 0; + status->y = 0; + status->z = 0; + + if (status->v0 < ((uint32_t)glide->config.trigger_px * 256)) { /* Q8 comparison */ + /* Not enough velocity to be worth gliding, abort */ + cursor_glide_stop(glide); + return invalid_report; + } + + return cursor_glide(glide); +} + +void cursor_glide_update(cursor_glide_context_t* glide, mouse_xy_report_t dx, mouse_xy_report_t dy, uint16_t z) { + cursor_glide_status_t* status = &glide->status; + + status->dx0 = dx; + status->dy0 = dy; + status->z = z; +} +#endif |