Make TextStyle !Copy

egui/src/menu.rs

@@ -414,7 +414,8 @@ impl SubMenuButton {
         let button_padding = ui.spacing().button_padding;
         let total_extra = button_padding + button_padding;
         let text_available_width = ui.available_width() - total_extra.x;
-        let text_galley = text.into_galley(ui, Some(true), text_available_width, text_style);
+        let text_galley =
+            text.into_galley(ui, Some(true), text_available_width, text_style.clone());
 
         let icon_available_width = text_available_width - text_galley.size().x;
         let icon_galley = icon.into_galley(ui, Some(true), icon_available_width, text_style);

egui/src/style.rs

@@ -581,8 +581,9 @@ impl Style {
         crate::Grid::new("_options").show(ui, |ui| {
             ui.label("Default body text style:");
             ui.horizontal(|ui| {
-                for &style in &[TextStyle::Body, TextStyle::Monospace] {
+                for style in [TextStyle::Body, TextStyle::Monospace] {
-                    let text = crate::RichText::new(format!("{:?}", style)).text_style(style);
+                    let text =
+                        crate::RichText::new(format!("{:?}", style)).text_style(style.clone());
                     ui.radio_value(body_text_style, style, text);
                 }
             });
@@ -597,7 +598,8 @@ impl Style {
                 .show_ui(ui, |ui| {
                     ui.selectable_value(override_text_style, None, "None");
                     for style in TextStyle::all() {
-                        let text = crate::RichText::new(format!("{:?}", style)).text_style(style);
+                        let text =
+                            crate::RichText::new(format!("{:?}", style)).text_style(style.clone());
                         ui.selectable_value(override_text_style, Some(style), text);
                     }
                 });

egui/src/widget_text.rs

@@ -173,9 +173,10 @@ impl RichText {
     pub fn font_height(&self, ctx: &Context) -> f32 {
         let text_style = self
             .text_style
-            .or(ctx.style().override_text_style)
+            .clone()
-            .unwrap_or(ctx.style().body_text_style);
+            .or_else(|| ctx.style().override_text_style.clone())
-        ctx.fonts().row_height(text_style)
+            .unwrap_or_else(|| ctx.style().body_text_style.clone());
+        ctx.fonts().row_height(&text_style)
     }
 
     fn into_text_job(
@@ -205,7 +206,7 @@ impl RichText {
         let text_color = text_color.unwrap_or(crate::Color32::TEMPORARY_COLOR);
 
         let text_style = text_style
-            .or(style.override_text_style)
+            .or_else(|| style.override_text_style.clone())
             .unwrap_or(default_text_style);
 
         let mut background_color = background_color;

egui/src/widgets/label.rs

@@ -82,9 +82,9 @@ impl Label {
         }
 
         let valign = ui.layout().vertical_align();
-        let mut text_job = self
+        let mut text_job =
-            .text
+            self.text
-            .into_text_job(ui.style(), ui.style().body_text_style, valign);
+                .into_text_job(ui.style(), ui.style().body_text_style.clone(), valign);
 
         let should_wrap = self.wrap.unwrap_or_else(|| ui.wrap_text());
         let available_width = ui.available_width();

egui/src/widgets/plot/items/mod.rs

@@ -684,7 +684,7 @@ impl PlotItem for Text {
         let pos = transform.position_from_value(&self.position);
         let galley = ui
             .fonts()
-            .layout_no_wrap(self.text.clone(), self.style, color);
+            .layout_no_wrap(self.text.clone(), self.style.clone(), color);
         let rect = self
             .anchor
             .anchor_rect(Rect::from_min_size(pos, galley.size()));

egui/src/widgets/plot/legend.rs

@@ -29,7 +29,7 @@ impl Corner {
 }
 
 /// The configuration for a plot legend.
-#[derive(Clone, Copy, PartialEq)]
+#[derive(Clone, PartialEq)]
 pub struct Legend {
     pub text_style: TextStyle,
     pub background_alpha: f32,
@@ -89,9 +89,11 @@ impl LegendEntry {
             hovered,
         } = self;
 
-        let galley =
+        let galley = ui.fonts().layout_delayed_color(
-            ui.fonts()
+            text,
-                .layout_delayed_color(text, ui.style().body_text_style, f32::INFINITY);
+            ui.style().body_text_style.clone(),
+            f32::INFINITY,
+        );
 
         let icon_size = galley.size().y;
         let icon_spacing = icon_size / 5.0;
@@ -236,7 +238,7 @@ impl Widget for &mut LegendWidget {
         let mut legend_ui = ui.child_ui(legend_rect, layout);
         legend_ui
             .scope(|ui| {
-                ui.style_mut().body_text_style = config.text_style;
+                ui.style_mut().body_text_style = config.text_style.clone();
                 let background_frame = Frame {
                     margin: vec2(8.0, 4.0),
                     corner_radius: ui.style().visuals.window_corner_radius,

egui/src/widgets/plot/mod.rs

@@ -741,7 +741,7 @@ impl PreparedPlot {
                 let color = color_from_alpha(ui, text_alpha);
                 let text = emath::round_to_decimals(value_main, 5).to_string(); // hack
 
-                let galley = ui.painter().layout_no_wrap(text, text_style, color);
+                let galley = ui.painter().layout_no_wrap(text, text_style.clone(), color);
 
                 let mut text_pos = pos_in_gui + vec2(1.0, -galley.size().y);
 

egui/src/widgets/slider.rs

@@ -469,7 +469,7 @@ impl<'a> Slider<'a> {
         let text_style = TextStyle::Button;
         let perpendicular = ui
             .fonts()
-            .row_height(text_style)
+            .row_height(&text_style)
             .at_least(ui.spacing().interact_size.y);
         let slider_response = self.allocate_slider_space(ui, perpendicular);
         self.slider_ui(ui, &slider_response);

egui/src/widgets/text_edit/builder.rs

@@ -351,9 +351,9 @@ impl<'t> TextEdit<'t> {
 
         let prev_text = text.as_ref().to_owned();
         let text_style = text_style
-            .or(ui.style().override_text_style)
+            .or_else(|| ui.style().override_text_style.clone())
-            .unwrap_or_else(|| ui.style().body_text_style);
+            .unwrap_or_else(|| ui.style().body_text_style.clone());
-        let row_height = ui.fonts().row_height(text_style);
+        let row_height = ui.fonts().row_height(&text_style);
         const MIN_WIDTH: f32 = 24.0; // Never make a `TextEdit` more narrow than this.
         let available_width = ui.available_width().at_least(MIN_WIDTH);
         let desired_width = desired_width.unwrap_or_else(|| ui.spacing().text_edit_width);
@@ -363,12 +363,13 @@ impl<'t> TextEdit<'t> {
             desired_width.min(available_width)
         };
 
+        let text_style_clone = text_style.clone();
         let mut default_layouter = move |ui: &Ui, text: &str, wrap_width: f32| {
             let text = mask_if_password(password, text);
             ui.fonts().layout_job(if multiline {
-                LayoutJob::simple(text, text_style, text_color, wrap_width)
+                LayoutJob::simple(text, text_style_clone.clone(), text_color, wrap_width)
             } else {
-                LayoutJob::simple_singleline(text, text_style, text_color)
+                LayoutJob::simple_singleline(text, text_style_clone.clone(), text_color)
             })
         };
 

egui_demo_lib/src/apps/demo/code_editor.rs

@@ -71,7 +71,7 @@ impl super::View for CodeEditor {
         ui.collapsing("Theme", |ui| {
             ui.group(|ui| {
                 theme.ui(ui);
-                theme.store_in_memory(ui.ctx());
+                theme.clone().store_in_memory(ui.ctx());
             });
         });
 

egui_demo_lib/src/apps/demo/code_example.rs

@@ -98,7 +98,7 @@ impl CodeExample {
         );
 
         ui.horizontal(|ui| {
-            let indentation = 8.0 * ui.fonts().glyph_width(egui::TextStyle::Monospace, ' ');
+            let indentation = 8.0 * ui.fonts().glyph_width(&egui::TextStyle::Monospace, ' ');
             let item_spacing = ui.spacing_mut().item_spacing;
             ui.add_space(indentation - item_spacing.x);
 

egui_demo_lib/src/apps/demo/font_book.rs

@@ -55,7 +55,11 @@ impl super::View for FontBook {
             .selected_text(format!("{:?}", self.text_style))
             .show_ui(ui, |ui| {
                 for style in egui::TextStyle::all() {
-                    ui.selectable_value(&mut self.text_style, style, format!("{:?}", style));
+                    ui.selectable_value(
+                        &mut self.text_style,
+                        style.clone(),
+                        format!("{:?}", style),
+                    );
                 }
             });
 
@@ -68,13 +72,16 @@ impl super::View for FontBook {
             }
         });
 
-        let text_style = self.text_style;
+        let text_style = self.text_style.clone();
         let filter = &self.filter;
-        let named_chars = self.named_chars.entry(text_style).or_insert_with(|| {
+        let named_chars = self
+            .named_chars
+            .entry(text_style.clone())
+            .or_insert_with(|| {
                 ui.fonts()
                     .lock()
                     .fonts
-                .font_mut(text_style)
+                    .font_mut(&text_style)
                     .characters()
                     .iter()
                     .filter(|chr| !chr.is_whitespace() && !chr.is_ascii_control())
@@ -91,12 +98,14 @@ impl super::View for FontBook {
                 for (&chr, name) in named_chars {
                     if filter.is_empty() || name.contains(filter) || *filter == chr.to_string() {
                         let button = egui::Button::new(
-                            egui::RichText::new(chr.to_string()).text_style(text_style),
+                            egui::RichText::new(chr.to_string()).text_style(text_style.clone()),
                         )
                         .frame(false);
 
                         let tooltip_ui = |ui: &mut egui::Ui| {
-                            ui.label(egui::RichText::new(chr.to_string()).text_style(text_style));
+                            ui.label(
+                                egui::RichText::new(chr.to_string()).text_style(text_style.clone()),
+                            );
                             ui.label(format!("{}\nU+{:X}\n\nClick to copy", name, chr as u32));
                         };
 

egui_demo_lib/src/apps/demo/misc_demo_window.rs

@@ -140,7 +140,7 @@ impl Widgets {
 
         ui.horizontal_wrapped(|ui| {
             // Trick so we don't have to add spaces in the text below:
-            let width = ui.fonts().glyph_width(TextStyle::Body, ' ');
+            let width = ui.fonts().glyph_width(&TextStyle::Body, ' ');
             ui.spacing_mut().item_spacing.x = width;
 
             ui.label(RichText::new("Text can have").color(Color32::from_rgb(110, 255, 110)));

egui_demo_lib/src/apps/demo/plot_demo.rs

@@ -262,7 +262,11 @@ impl Widget for &mut LegendDemo {
             ui.label("Text style:");
             ui.horizontal(|ui| {
                 TextStyle::all().for_each(|style| {
-                    ui.selectable_value(&mut config.text_style, style, format!("{:?}", style));
+                    ui.selectable_value(
+                        &mut config.text_style,
+                        style.clone(),
+                        format!("{:?}", style),
+                    );
                 });
             });
             ui.end_row();
@@ -284,7 +288,9 @@ impl Widget for &mut LegendDemo {
             ui.end_row();
         });
 
-        let legend_plot = Plot::new("legend_demo").legend(*config).data_aspect(1.0);
+        let legend_plot = Plot::new("legend_demo")
+            .legend(config.clone())
+            .data_aspect(1.0);
         legend_plot
             .show(ui, |plot_ui| {
                 plot_ui.line(LegendDemo::line_with_slope(0.5).name("lines"));

egui_demo_lib/src/apps/demo/scrolling.rs

@@ -81,7 +81,7 @@ fn huge_content_lines(ui: &mut egui::Ui) {
     ui.add_space(4.0);
 
     let text_style = TextStyle::Body;
-    let row_height = ui.fonts().row_height(text_style);
+    let row_height = ui.fonts().row_height(&text_style);
     let num_rows = 10_000;
     ScrollArea::vertical().auto_shrink([false; 2]).show_rows(
         ui,
@@ -102,7 +102,7 @@ fn huge_content_painter(ui: &mut egui::Ui) {
     ui.add_space(4.0);
 
     let text_style = TextStyle::Body;
-    let row_height = ui.fonts().row_height(text_style) + ui.spacing().item_spacing.y;
+    let row_height = ui.fonts().row_height(&text_style) + ui.spacing().item_spacing.y;
     let num_rows = 10_000;
 
     ScrollArea::vertical()
@@ -130,7 +130,7 @@ fn huge_content_painter(ui: &mut egui::Ui) {
                     pos2(x, y),
                     Align2::LEFT_TOP,
                     text,
-                    text_style,
+                    text_style.clone(),
                     ui.visuals().text_color(),
                 );
                 used_rect = used_rect.union(text_rect);
@@ -265,7 +265,7 @@ impl super::View for ScrollStickTo {
         ui.add_space(4.0);
 
         let text_style = TextStyle::Body;
-        let row_height = ui.fonts().row_height(text_style);
+        let row_height = ui.fonts().row_height(&text_style);
         ScrollArea::vertical().stick_to_bottom().show_rows(
             ui,
             row_height,

egui_demo_lib/src/easy_mark/easy_mark_viewer.rs

@@ -18,7 +18,7 @@ pub fn easy_mark_it<'em>(ui: &mut Ui, items: impl Iterator<Item = easy_mark::Ite
 
     ui.allocate_ui_with_layout(initial_size, layout, |ui| {
         ui.spacing_mut().item_spacing.x = 0.0;
-        let row_height = ui.fonts().row_height(TextStyle::Body);
+        let row_height = ui.fonts().row_height(&TextStyle::Body);
         ui.set_row_height(row_height);
 
         for item in items {
@@ -28,7 +28,7 @@ pub fn easy_mark_it<'em>(ui: &mut Ui, items: impl Iterator<Item = easy_mark::Ite
 }
 
 pub fn item_ui(ui: &mut Ui, item: easy_mark::Item<'_>) {
-    let row_height = ui.fonts().row_height(TextStyle::Body);
+    let row_height = ui.fonts().row_height(&TextStyle::Body);
     let one_indent = row_height / 2.0;
 
     match item {
@@ -134,7 +134,7 @@ fn rich_text_from_style(text: &str, style: &easy_mark::Style) -> RichText {
 }
 
 fn bullet_point(ui: &mut Ui, width: f32) -> Response {
-    let row_height = ui.fonts().row_height(TextStyle::Body);
+    let row_height = ui.fonts().row_height(&TextStyle::Body);
     let (rect, response) = ui.allocate_exact_size(vec2(width, row_height), Sense::hover());
     ui.painter().circle_filled(
         rect.center(),
@@ -145,7 +145,7 @@ fn bullet_point(ui: &mut Ui, width: f32) -> Response {
 }
 
 fn numbered_point(ui: &mut Ui, width: f32, number: &str) -> Response {
-    let row_height = ui.fonts().row_height(TextStyle::Body);
+    let row_height = ui.fonts().row_height(&TextStyle::Body);
     let (rect, response) = ui.allocate_exact_size(vec2(width, row_height), Sense::hover());
     let text = format!("{}.", number);
     let text_color = ui.visuals().strong_text_color();

egui_demo_lib/src/syntax_highlighting.rs

@@ -116,7 +116,7 @@ impl SyntectTheme {
     }
 }
 
-#[derive(Clone, Copy, Hash, PartialEq)]
+#[derive(Clone, Hash, PartialEq)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 #[cfg_attr(feature = "serde", serde(default))]
 pub struct CodeTheme {
@@ -158,15 +158,15 @@ impl CodeTheme {
         }
     }
 
-    pub fn store_in_memory(&self, ctx: &egui::Context) {
+    pub fn store_in_memory(self, ctx: &egui::Context) {
         if self.dark_mode {
             ctx.memory()
                 .data
-                .insert_persisted(egui::Id::new("dark"), *self);
+                .insert_persisted(egui::Id::new("dark"), self);
         } else {
             ctx.memory()
                 .data
-                .insert_persisted(egui::Id::new("light"), *self);
+                .insert_persisted(egui::Id::new("light"), self);
         }
     }
 }
@@ -206,12 +206,12 @@ impl CodeTheme {
         Self {
             dark_mode: true,
             formats: enum_map::enum_map![
-                TokenType::Comment => TextFormat::simple(text_style, Color32::from_gray(120)),
+                TokenType::Comment => TextFormat::simple(text_style.clone(), Color32::from_gray(120)),
-                TokenType::Keyword => TextFormat::simple(text_style, Color32::from_rgb(255, 100, 100)),
+                TokenType::Keyword => TextFormat::simple(text_style.clone(), Color32::from_rgb(255, 100, 100)),
-                TokenType::Literal => TextFormat::simple(text_style, Color32::from_rgb(87, 165, 171)),
+                TokenType::Literal => TextFormat::simple(text_style.clone(), Color32::from_rgb(87, 165, 171)),
-                TokenType::StringLiteral => TextFormat::simple(text_style, Color32::from_rgb(109, 147, 226)),
+                TokenType::StringLiteral => TextFormat::simple(text_style.clone(), Color32::from_rgb(109, 147, 226)),
-                TokenType::Punctuation => TextFormat::simple(text_style, Color32::LIGHT_GRAY),
+                TokenType::Punctuation => TextFormat::simple(text_style.clone(), Color32::LIGHT_GRAY),
-                TokenType::Whitespace => TextFormat::simple(text_style, Color32::TRANSPARENT),
+                TokenType::Whitespace => TextFormat::simple(text_style.clone(), Color32::TRANSPARENT),
             ],
         }
     }
@@ -223,12 +223,12 @@ impl CodeTheme {
             dark_mode: false,
             #[cfg(not(feature = "syntect"))]
             formats: enum_map::enum_map![
-                TokenType::Comment => TextFormat::simple(text_style, Color32::GRAY),
+                TokenType::Comment => TextFormat::simple(text_style.clone(), Color32::GRAY),
-                TokenType::Keyword => TextFormat::simple(text_style, Color32::from_rgb(235, 0, 0)),
+                TokenType::Keyword => TextFormat::simple(text_style.clone(), Color32::from_rgb(235, 0, 0)),
-                TokenType::Literal => TextFormat::simple(text_style, Color32::from_rgb(153, 134, 255)),
+                TokenType::Literal => TextFormat::simple(text_style.clone(), Color32::from_rgb(153, 134, 255)),
-                TokenType::StringLiteral => TextFormat::simple(text_style, Color32::from_rgb(37, 203, 105)),
+                TokenType::StringLiteral => TextFormat::simple(text_style.clone(), Color32::from_rgb(37, 203, 105)),
-                TokenType::Punctuation => TextFormat::simple(text_style, Color32::DARK_GRAY),
+                TokenType::Punctuation => TextFormat::simple(text_style.clone(), Color32::DARK_GRAY),
-                TokenType::Whitespace => TextFormat::simple(text_style, Color32::TRANSPARENT),
+                TokenType::Whitespace => TextFormat::simple(text_style.clone(), Color32::TRANSPARENT),
             ],
         }
     }
@@ -259,7 +259,7 @@ impl CodeTheme {
                         // (TokenType::Whitespace, "whitespace"),
                     ] {
                         let format = &mut self.formats[tt];
-                        ui.style_mut().override_text_style = Some(format.style);
+                        ui.style_mut().override_text_style = Some(format.style.clone());
                         ui.visuals_mut().override_text_color = Some(format.color);
                         ui.radio_value(&mut selected_tt, tt, tt_name);
                     }
@@ -412,7 +412,7 @@ impl Highligher {
         while !text.is_empty() {
             if text.starts_with("//") {
                 let end = text.find('\n').unwrap_or_else(|| text.len());
-                job.append(&text[..end], 0.0, theme.formats[TokenType::Comment]);
+                job.append(&text[..end], 0.0, theme.formats[TokenType::Comment].clone());
                 text = &text[end..];
             } else if text.starts_with('"') {
                 let end = text[1..]
@@ -420,7 +420,11 @@ impl Highligher {
                     .map(|i| i + 2)
                     .or_else(|| text.find('\n'))
                     .unwrap_or_else(|| text.len());
-                job.append(&text[..end], 0.0, theme.formats[TokenType::StringLiteral]);
+                job.append(
+                    &text[..end],
+                    0.0,
+                    theme.formats[TokenType::StringLiteral].clone(),
+                );
                 text = &text[end..];
             } else if text.starts_with(|c: char| c.is_ascii_alphanumeric()) {
                 let end = text[1..]
@@ -432,19 +436,27 @@ impl Highligher {
                 } else {
                     TokenType::Literal
                 };
-                job.append(word, 0.0, theme.formats[tt]);
+                job.append(word, 0.0, theme.formats[tt].clone());
                 text = &text[end..];
             } else if text.starts_with(|c: char| c.is_ascii_whitespace()) {
                 let end = text[1..]
                     .find(|c: char| !c.is_ascii_whitespace())
                     .map_or_else(|| text.len(), |i| i + 1);
-                job.append(&text[..end], 0.0, theme.formats[TokenType::Whitespace]);
+                job.append(
+                    &text[..end],
+                    0.0,
+                    theme.formats[TokenType::Whitespace].clone(),
+                );
                 text = &text[end..];
             } else {
                 let mut it = text.char_indices();
                 it.next();
                 let end = it.next().map_or(text.len(), |(idx, _chr)| idx);
-                job.append(&text[..end], 0.0, theme.formats[TokenType::Punctuation]);
+                job.append(
+                    &text[..end],
+                    0.0,
+                    theme.formats[TokenType::Punctuation].clone(),
+                );
                 text = &text[end..];
             }
         }

epaint/src/text/font.rs

@@ -270,8 +270,8 @@ impl Font {
     }
 
     #[inline(always)]
-    pub fn text_style(&self) -> TextStyle {
+    pub fn text_style(&self) -> &TextStyle {
-        self.text_style
+        &self.text_style
     }
 
     #[inline(always)]

epaint/src/text/fonts.rs

@@ -11,7 +11,7 @@ use crate::{
 
 // TODO: rename
 /// One of a few categories of styles of text, e.g. body, button or heading.
-#[derive(Copy, Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 #[cfg_attr(feature = "serde", serde(rename_all = "snake_case"))]
 pub enum TextStyle {
@@ -37,7 +37,7 @@ impl TextStyle {
             TextStyle::Monospace,
         ]
         .iter()
-        .copied()
+        .cloned()
     }
 }
 
@@ -270,13 +270,13 @@ impl Fonts {
 
     /// Width of this character in points.
     #[inline]
-    pub fn glyph_width(&self, text_style: TextStyle, c: char) -> f32 {
+    pub fn glyph_width(&self, text_style: &TextStyle, c: char) -> f32 {
         self.lock().fonts.glyph_width(text_style, c)
     }
 
     /// Height of one row of text. In points
     #[inline]
-    pub fn row_height(&self, text_style: TextStyle) -> f32 {
+    pub fn row_height(&self, text_style: &TextStyle) -> f32 {
         self.lock().fonts.row_height(text_style)
     }
 
@@ -398,17 +398,17 @@ impl FontsImpl {
         let fonts = definitions
             .family_and_size
             .iter()
-            .map(|(&text_style, &(family, scale_in_points))| {
+            .map(|(text_style, (family, scale_in_points))| {
-                let fonts = &definitions.fonts_for_family.get(&family);
+                let fonts = &definitions.fonts_for_family.get(family);
                 let fonts = fonts.unwrap_or_else(|| {
                     panic!("FontFamily::{:?} is not bound to any fonts", family)
                 });
                 let fonts: Vec<Arc<FontImpl>> = fonts
                     .iter()
-                    .map(|font_name| font_impl_cache.font_impl(font_name, scale_in_points))
+                    .map(|font_name| font_impl_cache.font_impl(font_name, *scale_in_points))
                     .collect();
 
-                (text_style, Font::new(text_style, fonts))
+                (text_style.clone(), Font::new(text_style.clone(), fonts))
             })
             .collect();
 
@@ -430,18 +430,18 @@ impl FontsImpl {
     }
 
     #[inline]
-    pub fn font_mut(&mut self, text_style: TextStyle) -> &mut Font {
+    pub fn font_mut(&mut self, text_style: &TextStyle) -> &mut Font {
-        self.fonts.get_mut(&text_style).unwrap()
+        self.fonts.get_mut(text_style).unwrap()
     }
 
     /// Width of this character in points.
-    fn glyph_width(&mut self, text_style: TextStyle, c: char) -> f32 {
+    fn glyph_width(&mut self, text_style: &TextStyle, c: char) -> f32 {
         self.font_mut(text_style).glyph_width(c)
     }
 
     /// Height of one row of text. In points
-    fn row_height(&self, text_style: TextStyle) -> f32 {
+    fn row_height(&mut self, text_style: &TextStyle) -> f32 {
-        self.fonts[&text_style].row_height()
+        self.font_mut(text_style).row_height()
     }
 }
 

epaint/src/text/text_layout.rs

@@ -86,7 +86,7 @@ fn layout_section(
         byte_range,
         format,
     } = section;
-    let font = fonts.font_mut(format.style);
+    let font = fonts.font_mut(&format.style);
     let font_height = font.row_height();
 
     let mut paragraph = out_paragraphs.last_mut().unwrap();

epaint/src/text/text_layout_types.rs

@@ -156,7 +156,7 @@ impl LayoutJob {
     pub fn font_height(&self, fonts: &crate::Fonts) -> f32 {
         let mut max_height = 0.0_f32;
         for section in &self.sections {
-            max_height = max_height.max(fonts.row_height(section.format.style));
+            max_height = max_height.max(fonts.row_height(&section.format.style));
         }
         max_height
     }
@@ -213,7 +213,7 @@ impl std::hash::Hash for LayoutSection {
 
 // ----------------------------------------------------------------------------
 
-#[derive(Copy, Clone, Debug, Hash, PartialEq)]
+#[derive(Clone, Debug, Hash, PartialEq)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct TextFormat {
     pub style: TextStyle,