From 8671aa26e1f65340c41f6b2c6f3ef2d6d80a6567 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Mon, 21 Nov 2022 17:33:23 +0100
Subject: [PATCH] Added support for thin space

https://en.wikipedia.org/wiki/Thin_space
---
 CHANGELOG.md                   |  1 +
 crates/epaint/CHANGELOG.md     |  3 ++-
 crates/epaint/src/text/font.rs | 17 +++++++++++++++++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c2ba1e13..80ed7f1a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,7 @@ NOTE: [`epaint`](crates/epaint/CHANGELOG.md), [`eframe`](crates/eframe/CHANGELOG
 * Added possibility to enable text wrap for the selected text of `egui::ComboBox` ([#2272](https://github.com/emilk/egui/pull/2244))
 * Added `Area::constrain` and `Window::constrain` which constrains area to the screen bounds. ([#2270](https://github.com/emilk/egui/pull/2270)).
 * Added `Area::pivot` and `Window::pivot` which controls what part of the window to position. ([#2303](https://github.com/emilk/egui/pull/2303)).
+* Added support for [thin space](https://en.wikipedia.org/wiki/Thin_space).
 
 ### Changed 🔧
 * Panels always have a separator line, but no stroke on other sides. Their spacing has also changed slightly ([#2261](https://github.com/emilk/egui/pull/2261)).
diff --git a/crates/epaint/CHANGELOG.md b/crates/epaint/CHANGELOG.md
index 1bf8fb01..a5b06d8e 100644
--- a/crates/epaint/CHANGELOG.md
+++ b/crates/epaint/CHANGELOG.md
@@ -5,7 +5,8 @@ All notable changes to the epaint crate will be documented in this file.
 ## Unreleased
 * ⚠️ BREAKING: Fix text being too small ([#2069](https://github.com/emilk/egui/pull/2069)).
 * ⚠️ BREAKING: epaint now expects integrations to do all color blending in gamma space ([#2071](https://github.com/emilk/egui/pull/2071)).
-* Add `Fonts::has_glyph(s)` for querying if a glyph is supported ([#2202](https://github.com/emilk/egui/pull/2202)).
+* Added `Fonts::has_glyph(s)` for querying if a glyph is supported ([#2202](https://github.com/emilk/egui/pull/2202)).
+* Added support for [thin space](https://en.wikipedia.org/wiki/Thin_space).
 
 
 ## 0.19.0 - 2022-08-20
diff --git a/crates/epaint/src/text/font.rs b/crates/epaint/src/text/font.rs
index ee0574ae..e93356ab 100644
--- a/crates/epaint/src/text/font.rs
+++ b/crates/epaint/src/text/font.rs
@@ -156,6 +156,23 @@ impl FontImpl {
             }
         }
 
+        if c == '\u{2009}' {
+            // Thin space, often used as thousands deliminator: 1 234 567 890
+            // https://www.compart.com/en/unicode/U+2009
+            // https://en.wikipedia.org/wiki/Thin_space
+
+            if let Some(space) = self.glyph_info(' ') {
+                let em = self.height_in_points; // TODO(emilk): is this right?
+                let advance_width = f32::min(em / 6.0, space.advance_width * 0.5);
+                let glyph_info = GlyphInfo {
+                    advance_width,
+                    ..GlyphInfo::default()
+                };
+                self.glyph_info_cache.write().insert(c, glyph_info);
+                return Some(glyph_info);
+            }
+        }
+
         // Add new character:
         use ab_glyph::Font as _;
         let glyph_id = self.ab_glyph_font.glyph_id(c);