Improve web frontend performance during zooming and panning (#3337)

* WIP debounce frontend ui updates

* Reduce the number of frontend updates performed

* Improve menu bar diffing

* Cleanup in dispatcher

* Fix comment

editor/src/messages/layout/utility_types/layout_widget.rs

@@ -484,13 +484,19 @@ impl LayoutGroup {
 	}
 }
 
-#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize, specta::Type)]
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize, specta::Type)]
 pub struct WidgetHolder {
 	#[serde(rename = "widgetId")]
 	pub widget_id: WidgetId,
 	pub widget: Widget,
 }
 
+impl PartialEq for WidgetHolder {
+	fn eq(&self, other: &Self) -> bool {
+		self.widget == other.widget
+	}
+}
+
 impl WidgetHolder {
 	#[deprecated(since = "0.0.0", note = "Please use the builder pattern, e.g. TextLabel::new(\"hello\").widget_holder()")]
 	pub fn new(widget: Widget) -> Self {
@@ -502,6 +508,26 @@ impl WidgetHolder {
 
 	/// Diffing updates self (where self is old) based on new, updating the list of modifications as it does so.
 	pub fn diff(&mut self, new: Self, widget_path: &mut [usize], widget_diffs: &mut Vec<WidgetDiff>) {
+		if let (Widget::PopoverButton(button1), Widget::PopoverButton(button2)) = (&mut self.widget, &new.widget) {
+			if button1.disabled == button2.disabled
+				&& button1.style == button2.style
+				&& button1.menu_direction == button2.menu_direction
+				&& button1.icon == button2.icon
+				&& button1.tooltip == button2.tooltip
+				&& button1.tooltip_shortcut == button2.tooltip_shortcut
+				&& button1.popover_min_width == button2.popover_min_width
+			{
+				let mut new_widget_path = widget_path.to_vec();
+				for (i, (a, b)) in button1.popover_layout.iter_mut().zip(button2.popover_layout.iter()).enumerate() {
+					new_widget_path.push(i);
+					a.diff(b.clone(), &mut new_widget_path, widget_diffs);
+					new_widget_path.pop();
+				}
+				self.widget = new.widget;
+				return;
+			}
+		}
+
 		// If there have been changes to the actual widget (not just the id)
 		if self.widget != new.widget {
 			// We should update to the new widget value as well as a new widget id

editor/src/messages/layout/utility_types/widgets/input_widgets.rs

@@ -19,6 +19,7 @@ pub struct CheckboxInput {
 	pub tooltip: String,
 
 	#[serde(rename = "forLabel")]
+	#[derivative(Debug = "ignore", PartialEq = "ignore")]
 	pub for_label: CheckboxId,
 
 	#[serde(skip)]

editor/src/messages/layout/utility_types/widgets/label_widgets.rs

@@ -36,7 +36,8 @@ pub enum SeparatorType {
 	Section,
 }
 
-#[derive(Clone, serde::Serialize, serde::Deserialize, Derivative, Debug, PartialEq, Eq, Default, WidgetBuilder, specta::Type)]
+#[derive(Clone, serde::Serialize, serde::Deserialize, Derivative, Debug, Eq, Default, WidgetBuilder, specta::Type)]
+#[derivative(PartialEq)]
 pub struct TextLabel {
 	pub disabled: bool,
 
@@ -62,6 +63,7 @@ pub struct TextLabel {
 	pub tooltip: String,
 
 	#[serde(rename = "forCheckbox")]
+	#[derivative(PartialEq = "ignore")]
 	pub for_checkbox: CheckboxId,
 
 	// Body