Ping?
It isn't a severe bug and it doesn't concern a spectacular feature,
but shouldn't we fix it?
On 04/16/2016 06:01 PM, Ulf Brosziewski wrote:
> The changes I have introduced in wsconscomm.c recently can make the
> transition from two-finger scrolling to coasting somewhat difficult.
> Provided that you have scrolled quickly enough, coasting will start
> if you finish the scroll gesture by lifting both fingers simultaneously,
> but a short delay will prevent coasting. When the contact count drops
> from 2 to 1 a RESET event will occur, and the handler clears the scroll
> flag.
>
> The diff below is a fix for this problem. The new version won't interrupt
> or stop scrolling, rather it ensures that the current coordinate deltas
> won't affect its speed or direction. I have tested it with my Elantech-v4
> touchpad.
>
> OK?
>
>
> Index: src/wsconscomm.c
> ===================================================================
> RCS file: /cvs/xenocara/driver/xf86-input-synaptics/src/wsconscomm.c,v
> retrieving revision 1.14
> diff -u -p -r1.14 wsconscomm.c
> --- src/wsconscomm.c 30 Mar 2016 23:33:34 -0000 1.14
> +++ src/wsconscomm.c 16 Apr 2016 15:15:46 -0000
> @@ -150,6 +150,21 @@ WSConsQueryHardware(InputInfoPtr pInfo)
> return WSConsIsTouchpad(pInfo, NULL);
> }
>
> +static void
> +WSConsAdjustScrollCoords(SynapticsPrivate *priv, struct SynapticsHwState *hw)
> +{
> + int dx, dy, i;
> +
> + dx = hw->x - priv->scroll.last_x;
> + dy = hw->y - priv->scroll.last_y;
> + priv->scroll.last_x = hw->x;
> + priv->scroll.last_y = hw->y;
> + for (i = 0; i < SYNAPTICS_MOVE_HISTORY; i++) {
> + priv->move_hist[i].x += dx;
> + priv->move_hist[i].y += dy;
> + }
> +}
> +
> static Bool
> WSConsReadHwState(InputInfoPtr pInfo,
> struct CommData *comm, struct SynapticsHwState *hwRet)
> @@ -158,7 +173,7 @@ WSConsReadHwState(InputInfoPtr pInfo,
> struct wsconscomm_proto_data *proto_data = priv->proto_data;
> struct SynapticsHwState *hw = comm->hwState;
> struct wscons_event *event;
> - Bool v;
> + Bool v, reset = FALSE;
>
> while ((event = WSConsGetEvent(pInfo)) != NULL) {
> switch (event->type) {
> @@ -229,15 +244,18 @@ WSConsReadHwState(InputInfoPtr pInfo,
> hw->fingerWidth = event->value;
> break;
> case WSCONS_EVENT_TOUCH_RESET:
> - /*
> - * The contact count or the active MT-slot has changed.
> - * Suppress pointer motion and two-finger scrolling.
> - */
> - priv->count_packet_finger = 0;
> - priv->vert_scroll_twofinger_on = FALSE;
> - priv->horiz_scroll_twofinger_on = FALSE;
> + /* The contact count or the active MT slot has changed. */
> + reset = TRUE;
> break;
> case WSCONS_EVENT_SYNC:
> + if (reset) {
> + /* Ensure that pointer motion stops. */
> + priv->count_packet_finger = 0;
> + if (priv->vert_scroll_twofinger_on
> + || priv->horiz_scroll_twofinger_on) {
> + WSConsAdjustScrollCoords(priv, hw);
> + }
> + }
> hw->millis = 1000 * event->time.tv_sec +
> event->time.tv_nsec / 1000000;
> SynapticsCopyHwState(hwRet, hw);
>
>
