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 <[email protected]> + * + * 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 | 
