Polished scrolling significantly

crates/gpui/src/platform/event.rs

@@ -19,6 +19,15 @@ pub struct ModifiersChangedEvent {
     pub cmd: bool,
 }
 
+/// The phase of a touch motion event.
+/// Based on the winit enum of the same name,
+#[derive(Clone, Copy, Debug)]
+pub enum TouchPhase {
+    Started,
+    Moved,
+    Ended,
+}
+
 #[derive(Clone, Copy, Debug, Default)]
 pub struct ScrollWheelEvent {
     pub position: Vector2F,
@@ -28,6 +37,8 @@ pub struct ScrollWheelEvent {
     pub alt: bool,
     pub shift: bool,
     pub cmd: bool,
+    /// If the platform supports returning the phase of a scroll wheel event, it will be stored here
+    pub phase: Option<TouchPhase>,
 }
 
 #[derive(Hash, PartialEq, Eq, Copy, Clone, Debug)]

crates/gpui/src/platform/mac/event.rs

@@ -3,10 +3,10 @@ use crate::{
     keymap::Keystroke,
     platform::{Event, NavigationDirection},
     KeyDownEvent, KeyUpEvent, ModifiersChangedEvent, MouseButton, MouseButtonEvent,
-    MouseMovedEvent, ScrollWheelEvent,
+    MouseMovedEvent, ScrollWheelEvent, TouchPhase,
 };
 use cocoa::{
-    appkit::{NSEvent, NSEventModifierFlags, NSEventType},
+    appkit::{NSEvent, NSEventModifierFlags, NSEventPhase, NSEventType},
     base::{id, YES},
     foundation::NSString as _,
 };
@@ -150,6 +150,14 @@ impl Event {
             NSEventType::NSScrollWheel => window_height.map(|window_height| {
                 let modifiers = native_event.modifierFlags();
 
+                let phase = match native_event.phase() {
+                    NSEventPhase::NSEventPhaseMayBegin | NSEventPhase::NSEventPhaseBegan => {
+                        Some(TouchPhase::Started)
+                    }
+                    NSEventPhase::NSEventPhaseEnded => Some(TouchPhase::Ended),
+                    _ => Some(TouchPhase::Moved),
+                };
+
                 Self::ScrollWheel(ScrollWheelEvent {
                     position: vec2f(
                         native_event.locationInWindow().x as f32,
@@ -159,6 +167,7 @@ impl Event {
                         native_event.scrollingDeltaX() as f32,
                         native_event.scrollingDeltaY() as f32,
                     ),
+                    phase,
                     precise: native_event.hasPreciseScrollingDeltas() == YES,
                     ctrl: modifiers.contains(NSEventModifierFlags::NSControlKeyMask),
                     alt: modifiers.contains(NSEventModifierFlags::NSAlternateKeyMask),