Add Korean translation (#234)

* Create ko.json

* Update ko.json

* Update i18n.rs

* Fonts: add a Hangul fallback so Korean doesn't render as boxes

Only the first CJK font found was loaded, and on Windows and macOS that is
a Japanese font without Hangul (Meiryo, Hiragino). Load the first readable
font of each group: the existing CJK list, then Malgun Gothic (Windows),
Apple SD Gothic Neo (macOS) or Nanum Gothic (Linux). Also rustfmt the
Korean catalog test.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RjGw4gA5ZvKrU8MQP6sBgT

---------

Co-authored-by: bherbruck <brennen.herbruck@gmail.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

crates/ui-egui/src/fonts.rs

@@ -1,13 +1,18 @@
-//! System font loading and fallback setup for multi-language (CJK/Japanese) support.
+//! System font loading and fallback setup for multi-language (CJK: Japanese, Chinese, Korean) support.
 //!
-//! The UI's Latin font always comes first; a CJK font is only ever appended as a fallback, so
-//! English text renders exactly as before and only glyphs the Latin font lacks use the CJK face.
+//! The UI's Latin font always comes first; a CJK font (then a Hangul font) is only ever appended as
+//! a fallback, so English text renders exactly as before and only glyphs the Latin font lacks use
+//! the CJK face. The Hangul fallback covers Korean where the CJK font found (Meiryo, Hiragino)
+//! lacks Hangul.
 
 use std::sync::Arc;
 
 /// Name of the CJK fallback entry in [`egui::FontDefinitions`].
 pub const CJK_FALLBACK: &str = "cjk_fallback";
 
+/// Name of the Hangul fallback entry in [`egui::FontDefinitions`], after [`CJK_FALLBACK`].
+pub const HANGUL_FALLBACK: &str = "hangul_fallback";
+
 /// UI languages whose text needs the CJK font. The web app's bundled font covers Japanese only;
 /// add Chinese or Korean here together with a font that covers them.
 pub const CJK_LANGUAGES: &[&str] = &["ja"];
@@ -19,13 +24,19 @@ pub fn needs_cjk_font(language: &str) -> bool {
 
 /// `fonts` with `bytes` appended as the last fallback of the Proportional and Monospace
 /// families, after the Latin UI font. `None` when the bytes are not a font.
-pub fn with_cjk_fallback(mut fonts: egui::FontDefinitions, bytes: Vec<u8>) -> Option<egui::FontDefinitions> {
+pub fn with_cjk_fallback(fonts: egui::FontDefinitions, bytes: Vec<u8>) -> Option<egui::FontDefinitions> {
+    with_fallback(fonts, CJK_FALLBACK, bytes)
+}
+
+/// `fonts` with `bytes` appended under `name` as the last fallback of the Proportional and
+/// Monospace families. `None` when the bytes are not a font.
+fn with_fallback(mut fonts: egui::FontDefinitions, name: &str, bytes: Vec<u8>) -> Option<egui::FontDefinitions> {
     ttf_parser::Face::parse(&bytes, 0).ok()?;
-    fonts.font_data.insert(CJK_FALLBACK.to_owned(), Arc::new(egui::FontData::from_owned(bytes)));
+    fonts.font_data.insert(name.to_owned(), Arc::new(egui::FontData::from_owned(bytes)));
     for family in [egui::FontFamily::Proportional, egui::FontFamily::Monospace] {
         let list = fonts.families.entry(family).or_default();
-        list.retain(|name| name != CJK_FALLBACK);
-        list.push(CJK_FALLBACK.to_owned());
+        list.retain(|entry| entry != name);
+        list.push(name.to_owned());
     }
     Some(fonts)
 }
@@ -183,6 +194,20 @@ const FONT_CANDIDATES: &[&str] = &[
     "/usr/share/fonts/cjkuni-uming/uming.ttc",
 ];
 
+/// Hangul fonts, appended after the CJK fallback so Korean renders even when the CJK font found
+/// is a Japanese one without Hangul (Meiryo, Hiragino).
+#[cfg(not(target_arch = "wasm32"))]
+const HANGUL_FONT_CANDIDATES: &[&str] = &[
+    // Windows: Malgun Gothic
+    "C:\\Windows\\Fonts\\malgun.ttf",
+    // macOS: Apple SD Gothic Neo
+    "/System/Library/Fonts/AppleSDGothicNeo.ttc",
+    "/System/Library/Fonts/Supplemental/AppleGothic.ttf",
+    // Linux: Nanum Gothic (Noto Sans CJK already covers Hangul)
+    "/usr/share/fonts/truetype/nanum/NanumGothic.ttf",
+    "/usr/share/fonts/nanum/NanumGothic.ttf",
+];
+
 #[cfg(not(target_arch = "wasm32"))]
 fn try_read_font(path: &std::path::Path) -> Option<Vec<u8>> {
     if let Ok(bytes) = std::fs::read(path)
@@ -298,11 +323,22 @@ fn find_system_cjk_font() -> Option<Vec<u8>> {
     None
 }
 
-/// Configure font definitions with system CJK fallback if available.
+/// Configure font definitions with system CJK and Hangul fallbacks where available.
 #[cfg(not(target_arch = "wasm32"))]
 pub fn setup_fonts(ctx: &egui::Context) {
-    if let Some(bytes) = find_system_cjk_font() {
-        install_cjk_font(ctx, bytes);
+    let mut fonts = egui::FontDefinitions::default();
+    let mut found = false;
+    if let Some(cjk) = find_system_cjk_font().and_then(|bytes| with_cjk_fallback(fonts.clone(), bytes)) {
+        fonts = cjk;
+        found = true;
+    }
+    let hangul = HANGUL_FONT_CANDIDATES.iter().find_map(|path| try_read_font(std::path::Path::new(path)));
+    if let Some(with_hangul) = hangul.and_then(|bytes| with_fallback(fonts.clone(), HANGUL_FALLBACK, bytes)) {
+        fonts = with_hangul;
+        found = true;
+    }
+    if found {
+        ctx.set_fonts(fonts);
     }
 }
 
@@ -339,6 +375,18 @@ mod tests {
         assert!(with_cjk_fallback(defaults, b"not a font".to_vec()).is_none());
     }
 
+    #[test]
+    fn hangul_font_falls_back_after_the_cjk_font() {
+        let defaults = egui::FontDefinitions::default();
+        let cjk = with_cjk_fallback(defaults.clone(), latin_font_bytes()).unwrap();
+        let fonts = with_fallback(cjk, HANGUL_FALLBACK, latin_font_bytes()).unwrap();
+        for family in [egui::FontFamily::Proportional, egui::FontFamily::Monospace] {
+            let list = &fonts.families[&family];
+            assert_eq!(list.first(), defaults.families[&family].first(), "the Latin UI font stays first");
+            assert_eq!(&list[list.len() - 2..], [CJK_FALLBACK, HANGUL_FALLBACK], "Hangul follows the CJK fallback");
+        }
+    }
+
     #[test]
     fn directory_scan_matches_cjk_fonts_only() {
         for cjk in [

crates/ui-egui/src/i18n.rs

@@ -34,7 +34,8 @@ impl Catalog {
 static ENGLISH: Catalog = Catalog::new("en", "English", include_str!("locales/en.json"));
 static JAPANESE: Catalog = Catalog::new("ja", "日本語", include_str!("locales/ja.json"));
 static GERMAN: Catalog = Catalog::new("de", "Deutsch", include_str!("locales/de.json"));
-pub const LOCALES: &[&Catalog] = &[&ENGLISH, &JAPANESE, &GERMAN];
+static KOREAN: Catalog = Catalog::new("ko", "한국어", include_str!("locales/ko.json"));
+pub const LOCALES: &[&Catalog] = &[&ENGLISH, &JAPANESE, &GERMAN, &KOREAN];
 
 pub fn is_supported(id: &str) -> bool {
     LOCALES.iter().any(|catalog| catalog.id == id)
@@ -250,6 +251,27 @@ mod tests {
         assert_eq!(Locale::for_language("en").dynamic("Sketch1"), "Sketch1");
     }
 
+    #[test]
+    fn korean_catalog_translates_keys_labels_and_browser_patterns() {
+        let ko = Locale::for_language("ko");
+        assert_eq!(ko.name(), "한국어");
+        assert!(is_supported("ko"));
+        assert_eq!(ko.text("ui.preferences"), "환경 설정");
+        assert_eq!(ko.label("Extrude"), "돌출");
+        assert_eq!(ko.label("CREATE SKETCH"), "스케치 만들기");
+        assert_eq!(ko.label("NonExistentKey"), "NonExistentKey");
+        assert_eq!(ko.format("document.save_changes", &[("name", "My {design}")]), "My {design}의 변경 사항을 저장하시겠습니까?");
+        assert_eq!(ko.format("dialog.selected_count", &[("count", "2")]), "↖ 2개 선택됨");
+        assert_eq!(ko.dynamic("Sketch1"), "스케치1");
+        assert_eq!(ko.dynamic("Body2"), "바디2");
+        assert_eq!(ko.dynamic("Component12"), "컴포넌트12");
+        assert_eq!(ko.dynamic("Units: mm"), "단위: mm");
+        assert_eq!(ko.dynamic("Precision: 3"), "정밀도: 3");
+        assert_eq!(ko.dynamic("Parameters (5)"), "매개변수 (5)");
+        assert_eq!(ko.dynamic("4 degrees of freedom"), "자유도 4개");
+        assert_eq!(ko.dynamic("Sketch of bracket"), "Sketch of bracket");
+    }
+
     #[test]
     fn render_scopes_restore_the_previous_language() {
         let _english = scope("en");

crates/ui-egui/src/locales/ko.json

@@ -0,0 +1,296 @@
+{
+  "browser.body_name": "바디{number}",
+  "browser.component_name": "컴포넌트{number}",
+  "browser.parameters": "매개변수 ({count})",
+  "browser.precision": "정밀도: {precision}",
+  "browser.sketch_name": "스케치{number}",
+  "browser.units": "단위: {units}",
+  "dialog.custom_axis": "↖ 사용자 정의 축",
+  "dialog.edit_title": "{title} 편집",
+  "dialog.select": "↖ 선택",
+  "dialog.selected_count": "↖ {count}개 선택됨",
+  "document.save_changes": "{name}의 변경 사항을 저장하시겠습니까?",
+  "document.unsaved_changes": "{name}에 저장되지 않은 변경 사항이 있습니다. 저장하지 않으면 변경 사항이 사라집니다.",
+  "sketch.degrees_of_freedom": "자유도 {count}개",
+  "sketch.draw_curves": "{linetype} 곡선 그리기",
+  "sketch.make_selection": "선택 항목을 {linetype}(으)로 변경",
+  "ui.1_degree_of_freedom": "자유도 1개",
+  "ui.3d_sketch": "3D 스케치",
+  "ui.about": "정보",
+  "ui.activate": "활성화",
+  "ui.active_component": "활성 컴포넌트",
+  "ui.agent_cursor": "에이전트 커서",
+  "ui.agent_cursor_speed": "에이전트 커서 속도",
+  "ui.all": "모두",
+  "ui.angle": "각도",
+  "ui.angle_decimals": "각도 소수점 자릿수",
+  "ui.animate_view_changes": "뷰 변경 애니메이션",
+  "ui.animation": "애니메이션",
+  "ui.animation_speed": "애니메이션 속도",
+  "ui.apply": "적용",
+  "ui.arc": "호",
+  "ui.assemble": "조립",
+  "ui.autosave_every": "자동 저장 간격",
+  "ui.axes": "축",
+  "ui.axis": "축",
+  "ui.bodies": "바디",
+  "ui.box": "박스",
+  "ui.break": "끊기",
+  "ui.cancel": "취소",
+  "ui.canvases": "캔버스",
+  "ui.centerline": "중심선",
+  "ui.chamfer": "모따기",
+  "ui.change_workspace": "작업 공간 변경",
+  "ui.chord_length": "현 길이",
+  "ui.circle": "원",
+  "ui.circular_pattern": "원형 패턴",
+  "ui.clear_recent": "최근 항목 지우기",
+  "ui.clear_the_selection": "선택 해제",
+  "ui.close": "닫기",
+  "ui.coil": "코일",
+  "ui.coincident": "일치",
+  "ui.collapse": "접기",
+  "ui.collinear": "동일 선상",
+  "ui.combine": "결합",
+  "ui.coming_later": "추후 지원 예정",
+  "ui.concentric": "동심",
+  "ui.conic_curve": "원뿔 곡선",
+  "ui.constant": "상수",
+  "ui.constraints_conflict": "구속 조건 충돌",
+  "ui.construct": "구성",
+  "ui.construction": "구성선",
+  "ui.copy": "복사",
+  "ui.counterbore": "카운터보어",
+  "ui.countersink": "카운터싱크",
+  "ui.create": "만들기",
+  "ui.create_sketch": "스케치 만들기",
+  "ui.current": "현재",
+  "ui.curvature": "곡률",
+  "ui.cut": "잘라내기",
+  "ui.cylinder": "원통",
+  "ui.dark": "어둡게",
+  "ui.default_modelling_orientation": "기본 모델링 방향",
+  "ui.degrees_of_freedom": "자유도",
+  "ui.delete": "삭제",
+  "ui.depth": "깊이",
+  "ui.design": "디자인",
+  "ui.diameter": "지름",
+  "ui.dimension": "치수",
+  "ui.direction": "방향",
+  "ui.distance": "거리",
+  "ui.distance_1": "거리 1",
+  "ui.distance_2": "거리 2",
+  "ui.document_settings": "문서 설정",
+  "ui.don_t_save": "저장 안 함",
+  "ui.draft": "구배",
+  "ui.drawing": "도면",
+  "ui.drill_point": "드릴 선단",
+  "ui.edit": "편집",
+  "ui.ellipse": "타원",
+  "ui.end_radius": "끝 반지름",
+  "ui.equal": "동일",
+  "ui.expand": "펼치기",
+  "ui.export_ellipsis": "내보내기...",
+  "ui.extend": "연장",
+  "ui.extent_type": "범위 유형",
+  "ui.extrude": "돌출",
+  "ui.features": "피처",
+  "ui.file": "파일",
+  "ui.fillet": "필렛",
+  "ui.finish_sketch": "스케치 종료",
+  "ui.fix_unfix": "고정/고정 해제",
+  "ui.flat": "플랫",
+  "ui.flip": "뒤집기",
+  "ui.front": "정면",
+  "ui.fully_constrained": "완전 구속",
+  "ui.general": "일반",
+  "ui.generative_design": "제너레이티브 디자인",
+  "ui.graphics": "그래픽",
+  "ui.heading_assemble": "조립",
+  "ui.heading_box": "박스",
+  "ui.heading_chamfer": "모따기",
+  "ui.heading_circular_pattern": "원형 패턴",
+  "ui.heading_coil": "코일",
+  "ui.heading_combine": "결합",
+  "ui.heading_construct": "구성",
+  "ui.heading_create": "만들기",
+  "ui.heading_create_sketch": "스케치 만들기",
+  "ui.heading_cylinder": "원통",
+  "ui.heading_design": "디자인",
+  "ui.heading_draft": "구배",
+  "ui.heading_edit": "편집",
+  "ui.heading_extrude": "돌출",
+  "ui.heading_fillet": "필렛",
+  "ui.heading_finish_sketch": "스케치 종료",
+  "ui.heading_front": "정면",
+  "ui.heading_hole": "구멍",
+  "ui.heading_home": "홈",
+  "ui.heading_insert": "삽입",
+  "ui.heading_inspect": "검사",
+  "ui.heading_loft": "로프트",
+  "ui.heading_measure": "측정",
+  "ui.heading_mesh": "메시",
+  "ui.heading_mirror": "대칭 복사",
+  "ui.heading_modify": "수정",
+  "ui.heading_move": "이동",
+  "ui.heading_offset_plane": "오프셋 평면",
+  "ui.heading_ok": "확인",
+  "ui.heading_parameters": "매개변수",
+  "ui.heading_pattern_on_path": "경로 패턴",
+  "ui.heading_pipe": "파이프",
+  "ui.heading_plane_at_angle": "각도 평면",
+  "ui.heading_plastic": "플라스틱",
+  "ui.heading_rectangular_pattern": "직사각형 패턴",
+  "ui.heading_revolve": "회전",
+  "ui.heading_right": "우측면",
+  "ui.heading_scale": "축척",
+  "ui.heading_section_analysis": "단면 분석",
+  "ui.heading_select": "선택",
+  "ui.heading_sheet_metal": "판금",
+  "ui.heading_shell": "쉘",
+  "ui.heading_sketch": "스케치",
+  "ui.heading_sketch_palette": "스케치 팔레트",
+  "ui.heading_solid": "솔리드",
+  "ui.heading_sphere": "구",
+  "ui.heading_split_body": "바디 분할",
+  "ui.heading_surface": "서피스",
+  "ui.heading_sweep": "스윕",
+  "ui.heading_thread": "나사산",
+  "ui.heading_top": "상면",
+  "ui.heading_torus": "토러스",
+  "ui.help": "도움말",
+  "ui.hide": "숨기기",
+  "ui.hole": "구멍",
+  "ui.hole_tap_type": "탭 유형",
+  "ui.hole_type": "구멍 유형",
+  "ui.home": "홈",
+  "ui.horizontal_vertical": "수평/수직",
+  "ui.insert": "삽입",
+  "ui.inspect": "검사",
+  "ui.intersect": "교차",
+  "ui.join": "접합",
+  "ui.joints": "조인트",
+  "ui.keyboard_shortcuts": "키보드 단축키",
+  "ui.language": "언어",
+  "ui.length_decimals": "길이 소수점 자릿수",
+  "ui.light": "밝게",
+  "ui.line": "선",
+  "ui.linetype": "선 종류",
+  "ui.loft": "로프트",
+  "ui.look_at": "바라보기",
+  "ui.manufacture": "제조",
+  "ui.measure": "측정",
+  "ui.midpoint": "중간점",
+  "ui.mirror": "대칭 복사",
+  "ui.modify": "수정",
+  "ui.move": "이동",
+  "ui.multiple": "다중",
+  "ui.named_views": "명명된 뷰",
+  "ui.navigation": "탐색",
+  "ui.new_body": "새 바디",
+  "ui.new_design": "새 디자인",
+  "ui.normal": "일반",
+  "ui.object_type": "객체 유형",
+  "ui.objects": "객체",
+  "ui.offer_to_stand_up_y_up_files": "Y-up 파일을 Z-up으로 세우도록 제안",
+  "ui.offset": "오프셋",
+  "ui.offset_plane": "오프셋 평면",
+  "ui.one_side": "한 방향",
+  "ui.open": "열기",
+  "ui.open_ellipsis": "열기...",
+  "ui.open_recent": "최근 항목 열기",
+  "ui.operation": "작업",
+  "ui.options": "옵션",
+  "ui.orbit_around": "궤도 회전 기준",
+  "ui.origin": "원점",
+  "ui.pan_zoom_orbit": "이동, 확대/축소, 궤도 회전",
+  "ui.parallel": "평행",
+  "ui.parameters": "매개변수",
+  "ui.paste": "붙여넣기",
+  "ui.path": "경로",
+  "ui.pattern_on_path": "경로 패턴",
+  "ui.perpendicular": "수직",
+  "ui.pipe": "파이프",
+  "ui.placement": "배치",
+  "ui.plane": "평면",
+  "ui.plane_at_angle": "각도 평면",
+  "ui.point": "점",
+  "ui.point_under_the_cursor": "커서 아래의 점",
+  "ui.points": "점",
+  "ui.polygon": "다각형",
+  "ui.preferences": "환경 설정",
+  "ui.profile": "프로파일",
+  "ui.profile_plane": "프로파일 평면",
+  "ui.profiles": "프로파일",
+  "ui.project": "투영",
+  "ui.quit": "종료",
+  "ui.radius": "반지름",
+  "ui.radius_type": "반지름 유형",
+  "ui.rectangle": "직사각형",
+  "ui.rectangular_pattern": "직사각형 패턴",
+  "ui.redo": "다시 실행",
+  "ui.render": "렌더",
+  "ui.reset_the_settings_on_this_page": "이 페이지의 설정 초기화",
+  "ui.restore_defaults": "기본값 복원",
+  "ui.reverse_zoom_direction": "확대/축소 방향 반전",
+  "ui.revolve": "회전",
+  "ui.right": "우측면",
+  "ui.save": "저장",
+  "ui.save_as": "다른 이름으로 저장",
+  "ui.save_as_ellipsis": "다른 이름으로 저장...",
+  "ui.scale": "축척",
+  "ui.section_analysis": "단면 분석",
+  "ui.select": "선택",
+  "ui.selection": "선택",
+  "ui.shell": "쉘",
+  "ui.show": "표시",
+  "ui.show_constraints": "구속 조건 표시",
+  "ui.show_dimensions": "치수 표시",
+  "ui.show_points": "점 표시",
+  "ui.show_profile": "프로파일 표시",
+  "ui.show_projected_geometries": "투영된 형상 표시",
+  "ui.simple": "단순",
+  "ui.simulation": "시뮬레이션",
+  "ui.single": "단일",
+  "ui.sketch": "스케치",
+  "ui.sketch_dimension": "스케치 치수",
+  "ui.sketch_grid": "스케치 격자",
+  "ui.sketch_scale": "스케치 축척",
+  "ui.sketches": "스케치",
+  "ui.slice": "슬라이스",
+  "ui.slot": "슬롯",
+  "ui.smooth": "부드럽게",
+  "ui.snap": "스냅",
+  "ui.sphere": "구",
+  "ui.spline": "스플라인",
+  "ui.split_body": "바디 분할",
+  "ui.start": "시작",
+  "ui.start_radius": "시작 반지름",
+  "ui.sweep": "스윕",
+  "ui.symmetric": "대칭",
+  "ui.symmetry": "대칭",
+  "ui.system": "시스템",
+  "ui.tangent": "접선",
+  "ui.taper_angle": "테이퍼 각도",
+  "ui.tapped": "탭",
+  "ui.text": "텍스트",
+  "ui.theme": "테마",
+  "ui.thickness": "두께",
+  "ui.thread": "나사산",
+  "ui.tip_angle": "선단 각도",
+  "ui.to_object": "객체까지",
+  "ui.top": "상면",
+  "ui.torus": "토러스",
+  "ui.trim": "트림",
+  "ui.two_sides": "양방향",
+  "ui.ui_scale": "UI 배율",
+  "ui.undo": "실행 취소",
+  "ui.units": "단위",
+  "ui.units_of_new_designs": "새 디자인의 단위",
+  "ui.untitled": "제목 없음",
+  "ui.variable": "가변",
+  "ui.view_centre": "뷰 중심",
+  "ui.visual_style": "시각 스타일",
+  "ui.workspace": "작업 공간",
+  "ui.zoom_to_the_cursor": "커서 위치로 확대/축소"
+}