Complete overhaul of State structure.

Author: abey79

crates/re_ui/src/list_item2/list_item.rs

@@ -2,7 +2,7 @@
 
 use egui::{NumExt, Response, Shape, Ui};
 
-use crate::list_item2::{ContentContext, DesiredWidth, ListItemContent, StateStack};
+use crate::list_item2::{ContentContext, DesiredWidth, LayoutInfoStack, ListItemContent};
 use crate::ReUi;
 
 struct ListItemResponse {
@@ -238,10 +238,10 @@ impl<'a> ListItem<'a> {
 
         // We use the state set by ListItemContainer to determine how far the background should
         // extend.
-        let state = StateStack::top(ui.ctx());
+        let layout_info = LayoutInfoStack::top(ui.ctx());
         let mut bg_rect = rect;
-        bg_rect.set_left(state.background_x_range.min);
-        bg_rect.set_right(state.background_x_range.max);
+        bg_rect.set_left(layout_info.background_x_range.min);
+        bg_rect.set_right(layout_info.background_x_range.max);
 
         // We want to be able to select/hover the item across its full span, so we interact over the
         // entire background rect. But…
@@ -295,6 +295,7 @@ impl<'a> ListItem<'a> {
                 bg_rect,
                 response: &style_response,
                 list_item: &self,
+                layout_info,
             };
             content.ui(re_ui, ui, &content_ctx);
 

crates/re_ui/src/list_item2/mod.rs

@@ -34,6 +34,9 @@ pub struct ContentContext<'a> {
 
     /// The current list item.
     pub list_item: &'a ListItem<'a>,
+
+    /// Layout information to use for rendering.
+    pub layout_info: LayoutInfo,
 }
 
 #[derive(Debug, Clone, Copy)]

crates/re_ui/src/list_item2/property_content.rs

@@ -179,9 +179,9 @@ impl ListItemContent for PropertyContent<'_> {
         } = *self;
 
         // │                                                                              │
-        // │◀─────────────────────────────background_x_range─────────────────────────────▶│
+        // │◀─────────────────────layout_info.background_x_range─────────────────────────▶│
         // │                                                                              │
-        // │ ◀───────────state.left_column_width────────────▶│┌──COLUMN_SPACING           │
+        // │ ◀────────layout_info.left_column_width─────────▶│┌──COLUMN_SPACING           │
         // │                                                  ▼                           │
         // │                       ◀─────────────────────────┼────────context.rect──────▶ │
         // │ ┌ ─ ─ ─ ─ ┬ ─ ─ ─ ─ ┬ ┬────────┬─┬─────────────┬─┬─────────────┬─┬─────────┐ │
@@ -192,18 +192,17 @@ impl ListItemContent for PropertyContent<'_> {
         // │                       │        │ │             │││             │ │         │ │
         // │ └ ─ ─ ─ ─ ┴ ─ ─ ─ ─ ┴ ┴────────┴─┴─────────────┴─┴─────────────┴─┴─────────┘ │
         // │ ▲                     ▲         ▲               │               ▲            │
-        // │ └──state.left_x       │         └───────────────────────────────┤            │
+        // │ └──layout_info.left   │         └───────────────────────────────┤            │
         // │                       │                         ▲               │            │
-        // │       content_left_x──┘           mid_point_x───┘     text_to_icon_padding   │
+        // │       content_left_x──┘           mid_point_x───┘    text_to_icon_padding()  │
         // │                                                                              │
 
-        let state = super::StateStack::top(ui.ctx());
-
         let content_left_x = context.rect.left();
         // Total indent left of the content rect. This is part of the left column width.
-        let content_indent = content_left_x - state.left_x;
-        let mid_point_x = state.left_x
-            + state
+        let content_indent = content_left_x - context.layout_info.left_x;
+        let mid_point_x = context.layout_info.left_x
+            + context
+                .layout_info
                 .left_column_width
                 .unwrap_or_else(|| content_indent + (context.rect.width() / 2.).at_least(0.0));
 
@@ -217,7 +216,7 @@ impl ListItemContent for PropertyContent<'_> {
         let action_button_dimension =
             ReUi::small_icon_size().x + 2.0 * ui.spacing().button_padding.x;
         let reserve_action_button_space =
-            action_buttons.is_some() || state.reserve_action_button_space;
+            action_buttons.is_some() || context.layout_info.reserve_action_button_space;
         let action_button_extra = if reserve_action_button_space {
             action_button_dimension + ReUi::text_to_icon_padding()
         } else {
@@ -258,10 +257,12 @@ impl ListItemContent for PropertyContent<'_> {
             (content_indent + icon_extra + desired_galley.size().x + Self::COLUMN_SPACING / 2.0)
                 .ceil();
 
-        super::StateStack::top_mut(ui.ctx(), |state| {
-            state.register_desired_left_column_width(desired_width);
-            state.reserve_action_button_space(action_buttons.is_some());
-        });
+        context
+            .layout_info
+            .register_desired_left_column_width(ui.ctx(), desired_width);
+        context
+            .layout_info
+            .reserve_action_button_space(ui.ctx(), action_buttons.is_some());
 
         let galley = if desired_galley.size().x <= label_rect.width() {
             desired_galley