Move Pointing Device code to a subdirectory (#17684)

quantum/pointing_device/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