diff options
| -rw-r--r-- | src/layout/scrolling.rs | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/src/layout/scrolling.rs b/src/layout/scrolling.rs index 03eb1552..d559c281 100644 --- a/src/layout/scrolling.rs +++ b/src/layout/scrolling.rs @@ -145,6 +145,10 @@ pub(super) struct ViewGesture { // If this gesture is for drag-and-drop scrolling, this is the last event's unadjusted // timestamp. dnd_last_event_time: Option<Duration>, + // Time when the drag-and-drop scroll delta became non-zero, used for debouncing. + // + // If `None` then the scroll delta is currently zero. + dnd_nonzero_start_time: Option<Duration>, } #[derive(Debug)] @@ -335,7 +339,15 @@ impl<W: LayoutElement> ScrollingSpace<W> { // This happens after any dnd_scroll_gesture_scroll() calls (in // Layout::advance_animations()), so it doesn't mess up the time delta there. if let Some(last_time) = &mut gesture.dnd_last_event_time { - *last_time = self.clock.now_unadjusted(); + let now = self.clock.now_unadjusted(); + if *last_time != now { + *last_time = now; + + // If last_time was already == now, then dnd_scroll_gesture_scroll() must've + // updated the gesture already. Therefore, when this code runs, the pointer + // must be outside the DnD scrolling zone. + gesture.dnd_nonzero_start_time = None; + } } } @@ -2727,6 +2739,7 @@ impl<W: LayoutElement> ScrollingSpace<W> { stationary_view_offset: self.view_offset.stationary(), is_touchpad, dnd_last_event_time: None, + dnd_nonzero_start_time: None, }; self.view_offset = ViewOffset::Gesture(gesture); } @@ -2748,6 +2761,7 @@ impl<W: LayoutElement> ScrollingSpace<W> { stationary_view_offset: self.view_offset.stationary(), is_touchpad: false, dnd_last_event_time: Some(self.clock.now_unadjusted()), + dnd_nonzero_start_time: None, }; self.view_offset = ViewOffset::Gesture(gesture); @@ -2794,6 +2808,21 @@ impl<W: LayoutElement> ScrollingSpace<W> { let now = self.clock.now_unadjusted(); gesture.dnd_last_event_time = Some(now); + + if delta == 0. { + // We're outside the scrolling zone. + gesture.dnd_nonzero_start_time = None; + return; + } + + let nonzero_start = *gesture.dnd_nonzero_start_time.get_or_insert(now); + + // Delay starting the gesture a bit to avoid unwanted movement when dragging across + // monitors. + if now.saturating_sub(nonzero_start) < Duration::from_millis(50) { + return; + } + let time_delta = now.saturating_sub(last_time).as_secs_f64(); let delta = delta * time_delta * 50.; |