From b7e11af52ed1785354b8915d3d2fad7e0588b7d5 Mon Sep 17 00:00:00 2001
From: adrien <221212@umons.ac.be>
Date: Tue, 17 Mar 2026 17:39:57 +0100
Subject: [PATCH] rename comment & variable, add const root class for root ui

---
 crates/egui/src/ui.rs               | 18 ++++++++----------
 crates/egui/src/widget_style.rs     | 27 +++------------------------
 examples/styling_engine/src/main.rs |  6 ++++--
 3 files changed, 15 insertions(+), 36 deletions(-)

diff --git a/crates/egui/src/ui.rs b/crates/egui/src/ui.rs
index e7905c87d..096e558bf 100644
--- a/crates/egui/src/ui.rs
+++ b/crates/egui/src/ui.rs
@@ -7,6 +7,7 @@ use emath::GuiRounding as _;
 use epaint::mutex::RwLock;
 
 use crate::containers::menu;
+use crate::widget_style::{HasClasses as _, ROOT_CLASS};
 use crate::{containers::*, ecolor::*, layout::*, placer::Placer, widgets::*, *};
 // ----------------------------------------------------------------------------
 
@@ -113,7 +114,7 @@ impl Ui {
         let UiBuilder {
             id_salt,
             global_scope: _,
-            mut ui_stack_info,
+            ui_stack_info,
             layer_id,
             max_rect,
             layout,
@@ -123,7 +124,7 @@ impl Ui {
             style,
             sense,
             accessibility_parent,
-            classes: modifiers,
+            classes,
         } = ui_builder;
 
         let layer_id = layer_id.unwrap_or_else(LayerId::background);
@@ -139,10 +140,7 @@ impl Ui {
         let disabled = disabled || invisible;
         let style = style.unwrap_or_else(|| ctx.global_style());
         let sense = sense.unwrap_or_else(Sense::hover);
-        let modifiers = modifiers.unwrap_or_default();
-
-        // Temporary use of user tags as proof of concept
-        ui_stack_info = ui_stack_info.with_tag("root");
+        let classes = classes.unwrap_or_default().with_class(ROOT_CLASS);
 
         let placer = Placer::new(max_rect, layout);
         let ui_stack = UiStack {
@@ -152,7 +150,7 @@ impl Ui {
             parent: None,
             min_rect: placer.min_rect(),
             max_rect: placer.max_rect(),
-            classes: modifiers,
+            classes,
         };
 
         let mut ui = Ui {
@@ -268,7 +266,7 @@ impl Ui {
             style,
             sense,
             accessibility_parent,
-            classes: modifiers,
+            classes,
         } = ui_builder;
 
         let mut painter = self.painter.clone();
@@ -286,7 +284,7 @@ impl Ui {
         let sizing_pass = self.sizing_pass || sizing_pass;
         let style = style.unwrap_or_else(|| Arc::clone(&self.style));
         let sense = sense.unwrap_or_else(Sense::hover);
-        let modifiers = modifiers.unwrap_or_default();
+        let classes = classes.unwrap_or_default();
 
         if sizing_pass {
             // During the sizing pass we want widgets to use up as little space as possible,
@@ -318,7 +316,7 @@ impl Ui {
             parent: Some(Arc::clone(&self.stack)),
             min_rect: placer.min_rect(),
             max_rect: placer.max_rect(),
-            classes: modifiers,
+            classes,
         };
 
         let mut child_ui = Ui {
diff --git a/crates/egui/src/widget_style.rs b/crates/egui/src/widget_style.rs
index 24add2b6d..eb8a5dbe7 100644
--- a/crates/egui/src/widget_style.rs
+++ b/crates/egui/src/widget_style.rs
@@ -202,6 +202,8 @@ impl Style {
     }
 }
 
+pub const ROOT_CLASS: &str = "root";
+
 pub type ClassName = Cow<'static, str>;
 
 #[derive(Debug, Default, Clone)]
@@ -280,31 +282,8 @@ pub trait HasClasses {
         self
     }
 
-    /// Return true if the modifier is present in the list
+    /// Return true if the class is present in the list
     fn has(&self, class: impl Into<ClassName>) -> bool {
         self.classes().classes.contains(&class.into())
     }
 }
-
-/// Add a shortcut to add modifiers. The syntax is `add_modifiers`!(Name: (modifier1, modifier2, modifier3,)) for any number of modifiers
-#[macro_export]
-macro_rules! define_modifiers {
-    ($trait_name:ident: ($( $name:ident )+),?) => {
-
-        pub trait $trait_name {
-            $(
-                fn $name(self) -> Self;
-            )*
-        }
-
-        impl<T> $trait_name for T
-        where
-            T: HasModifiers,
-        {
-                #[inline]
-                $(fn $name(mut self) -> Self {
-                    self.with_class(stringify!($name))
-                })?
-        }
-    };
-}
diff --git a/examples/styling_engine/src/main.rs b/examples/styling_engine/src/main.rs
index eb311fde5..4a2ee6dc7 100644
--- a/examples/styling_engine/src/main.rs
+++ b/examples/styling_engine/src/main.rs
@@ -49,7 +49,9 @@ fn main() -> eframe::Result {
                                         while let Some(p) = parent {
                                             text.push(format!(
                                                 "{}{}class : '{}', kind : {:?}",
-                                                " ".repeat((2 * 0_i32.max(i - 1)) as usize),
+                                                " ".repeat(
+                                                    (2 * 0_i32.max(i - 1) + 1.min(i)) as usize
+                                                ),
                                                 if i > 0 { "\\- " } else { "" },
                                                 p.classes,
                                                 p.kind()
@@ -58,7 +60,7 @@ fn main() -> eframe::Result {
                                             parent = p.parent.as_ref();
                                         }
                                         ui.label(format!(
-                                            "Current hierarchy :\n{}",
+                                            "Current hierarchy (child to root):\n{}",
                                             text.join("\n")
                                         ));
                                     },