feat: add UI translation system (i18n) with live language switching#735
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foXaCe wants to merge 17 commits into
Open
feat: add UI translation system (i18n) with live language switching#735foXaCe wants to merge 17 commits into
foXaCe wants to merge 17 commits into
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Adds a runtime translation layer so all user-facing strings can be
localized without restarting the app. English ships as the reference
language; French is bundled as a complete second locale (425 keys).
## Architecture
- New `workspace/all/common/i18n.{c,h}` — minimal i18n core:
- Hash table (FNV-1a, 1024 buckets, 32 KB arena)
- Parser for plain `key=value` `.lang` files (no JSON dep)
- Lookup `T(key)` returns the translated string, or the input
verbatim when no entry matches → safe fallback
- `I18N_init(code)` called from `GFX_init`; `I18N_reload(code)`
hot-swaps the table at runtime
- New `skeleton/SYSTEM/res/lang/{en,fr}.lang` (425 key pairs)
- `NextUISettings.language[8]` persisted in `minuisettings.txt`
(defaults to "en"; backward-compatible read)
## Coverage
All user-visible strings are passed through `T()`:
- Launcher: `workspace/all/nextui/nextui.c`
- In-game menu: `workspace/all/minarch/{ma_menu,ma_frontend_opts,
ma_saves,ra_integration}.c`
- Settings UI (`workspace/all/settings/*.cpp/hpp`): main menus,
Appearance, Display, Audio, System, FN switch, In-Game,
RetroAchievements (including sync overlay messages), About,
Bluetooth, WiFi, color picker, keyboard prompt
- Hardware hints in `workspace/all/common/api.c`
- Tools: `battery`, `clock`, `gametime`, `ledcontrol`, `minput`,
`bootlogo` (button hints + on-screen labels)
## Hot-reload (Settings only)
`Settings → System → Language` switches locale live without exit:
- `AbstractMenuItem::getName/getDesc` and `MenuItem::getLabel/getLabels`
now call `T()` at each access (storing i18n keys, not pre-translated
strings)
- `ScopedOverlay` and `MenuList::showOverlay` apply `T()` internally
- `getRawName()` added for `selectByName` so selection survives a
language change
- Other apps (launcher, minarch, tools) load the active language on
startup — since they're short-lived processes relaunched per action,
no hot-reload is required there
## Build
- `i18n.c` linked into every app that calls `T()`: `nextui`, `minarch`,
`settings`, `battery`, `clock`, `gametime`, `ledcontrol`, `minput`,
`bootlogo` (9 makefiles updated)
- Pure C module; safe to include from C++ via `extern "C"` (already
done in `settings/menu.hpp`)
## Compatibility
- Default behavior unchanged: with no `.lang` files installed or
`language=en`, every `T(key)` falls back to the literal key — which
for legacy strings is the original English text → zero regression
- New `language=` line appended to `minuisettings.txt` (older
consumers can simply ignore it)
- Adding a new locale = drop `<code>.lang` into `.system/res/lang/`;
it is auto-discovered by Settings via `discoverLanguages()`
Covers the ~30 options of the in-game Frontend menu (MENU → Options →
Frontend during gameplay) plus their option-value labels. Adds ~90 new
key pairs to en.lang and fr.lang (total: 514 keys).
## Changes
- workspace/all/minarch/ma_config.c
- Replace literal English strings in .name / .desc with i18n keys
(e.g. `"Screen Scaling"` → `"frontend.opt.screen_scaling"`)
- Replace label arrays (onoff_labels, scaling_labels, resample_labels,
rewind_enable_labels, rewind_compression_accel_labels,
ambient_labels, effect_labels, overlay_labels) with key-based
entries
- getScreenScalingDesc() returns a key instead of a literal
- workspace/all/minarch/ma_menu.c
- Wrap rendering sites in T() so the displayed text is translated at
each frame (live-reloadable):
- item->name (3 sites)
- item->values[item->value] (1 site)
- item->values[j] (size calc, 1 site)
- list/item->desc footer (size + blit, 2 sites)
- skeleton/SYSTEM/res/lang/en.lang
- skeleton/SYSTEM/res/lang/fr.lang
- +~90 paired keys covering option names, descriptions, and value
labels for the Frontend menu
…ollections)
The main launcher built its root menu through Entry_new(path, ENTRY_DIR),
which derives the displayed name from the directory path
(getDisplayName()), bypassing translation. Switch those root entries to
Entry_newNamed with i18n keys so the labels render in the active
language.
## Changes
- workspace/all/nextui/nextui.c
- getRoot(): Tools / Recently Played / Collections now built with
Entry_newNamed + T() keys
- getQuickEntries(): same fix for the Quickswitcher entries
- skeleton/SYSTEM/res/lang/en.lang
- skeleton/SYSTEM/res/lang/fr.lang
- +3 paired keys: launcher.tools, launcher.recently_played,
launcher.collections
Brings total to 517 paired keys.
Open
8 tasks
Pass the derived display name through T() in Entry_new so well-known
pak and folder names (Settings, Updater, Pak Store, ...) can be
localised via the .lang files without renaming the actual directories
on disk.
Behaviour:
- en.lang lists each key with the original English value as its value,
so English users see no change (T() returns "Settings" → "Settings").
- fr.lang translates the entries that have a natural French equivalent
(Settings → Réglages, Updater → Mise à jour, USB Mass Storage →
Stockage USB, ...). Proper nouns (Pak Store, ScrapeGoat, LED'oh!)
are deliberately left untranslated.
- ROM folders, custom paks, and any name not present in the .lang fall
back to the raw input — zero risk of regression for third-party
content.
Extending the list = one line per locale (e.g. `MyPak=Mon Pak` in
fr.lang). No code change needed.
Brings total to 534 paired keys.
## Files
- workspace/all/nextui/nextui.c
- Entry_new now wraps the getDisplayName() result with T()
- skeleton/SYSTEM/res/lang/en.lang
- skeleton/SYSTEM/res/lang/fr.lang
- +17 pak / tool folder name keys covering the bundled and most
popular community paks
Third-party pak names are their authors' identity — translating them
would be confusing and would diverge from how the rest of the ecosystem
(Discord, README, screenshots) refers to them. Restrict Entry_new's
T() fallthrough to NextUI-bundled paks only:
Kept (NextUI core, workspace/all/*):
Settings, Battery, Clock, Game Tracker, Bootlogo, Input, LedControl
+ USB Mass Storage (third-party but a generic technical term)
Removed (third-party — keep author name):
Updater, Aesthetics, Pak Store, Files, Gallery, Remove Loading,
Artwork Scraper, Another Cheat Downloader, ScrapeGoat, LED'oh!, ...
Behaviour unchanged for these: T("Aesthetics") has no entry → falls
back to "Aesthetics" verbatim, so they render exactly as before.
The Battery tool's hints were already translated but the on-screen
labels (Since Charge, Current, Remaining, Longest), the zoom title
(Battery usage: Last N hours) and the "calculating" placeholder were
still rendered with hard-coded English strings.
## Changes
- workspace/all/battery/battery.c
- Format strings (battery.{since_charge,current,remaining,longest}_fmt)
are now resolved via T() so each label is translated at draw time.
- The zoom title goes through T("battery.usage_fmt") with the time
range itself (T("battery.range.{4h,8h,16h}")) as the format arg.
- The "calculating" placeholder in session_left is refreshed from
T("battery.calculating") right after GFX_init has loaded the
language. Buffer grown from 12 to 32 bytes to hold longer
translations.
- skeleton/SYSTEM/res/lang/{en,fr}.lang
- +9 new keys (battery.*).
- French range labels deliberately kept short ("4 dern. h" instead of
"4 dernières heures") so they fit in the title pill alongside the
"Utilisation batterie :" prefix.
… batterie') The Battery tool already shows a battery icon in the corner — having the word 'batterie' in the title is redundant in French and pushed the time- range suffix off-screen. Dropping it lets 'Utilisation : 16 dernières heures' fit on a single line, no abbreviation needed.
Refined the previous rule. Brand names (Aesthetics, ScrapeGoat, LED'oh!, Pak Store, Updater) stay untouched, but generic descriptive names that map 1:1 across languages and read as function labels (Files → Fichiers, Gallery → Galerie) should follow translation like the other system tools.
minui-presenter is shared by several third-party paks (Gallery, Artwork Scraper, Another Cheat Downloader, ...) that pass English UI labels (EXIT, OK, CANCEL, ...) via the --action-text / --cancel-text options. With i18n now wired into minui-presenter (https://github.com/josegonzalez/minui-presenter PR pending), those literals can be re-mapped to localised strings without modifying each pak's launch.sh — provided the lang file lists a key with the literal's exact spelling. Adds the matching keys to NextUI's central en/fr lang files.
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minui-presenter is shared by many third-party MinUI/NextUI paks (Gallery, Artwork Scraper, Another Cheat Downloader, ...) and the button labels it draws were hard-coded English. With NextUI now shipping an i18n system (see LoveRetro/NextUI#735), the presenter can read the same `language=` setting and localise its labels — both the built-in defaults and the strings passed by paks via --action-text/--cancel-text/... ## What it does - Reads `/mnt/SDCARD/.userdata/shared/minuisettings.txt` once at startup to discover the active language (`language=fr`, `language=en`, ...); falls back to English if the file or the key is missing. - Loads the matching `<code>.lang` file from `/mnt/SDCARD/.system/res/lang/` into a small open-addressed hash table (FNV-1a, 4096 buckets, 256 KB arena). Lookups are ~80 ns on a Cortex-A53. - Replaces the default button text constants (ACTION / SELECT / BACK / OTHER) with `T()` calls using `mp.btn.*` keys. - **Bonus**: after argv parsing, runs the caller-provided button texts through `T()` as well. So a pak that already passes `--cancel-text "EXIT"` doesn't need to change anything — as soon as the lang file contains `EXIT=QUITTER`, the bottom-right button reads "QUITTER" on a French system. ## Files - `include/i18n/i18n.{c,h}` — pure-C i18n core (adapted from the NextUI PR — same parser, same hash table, same fallback semantics). Depends only on `defines.h` (already in the include path via the toolchain's shared common/) for `SDCARD_PATH` and `MAX_PATH`. - `lang/en.lang`, `lang/fr.lang` — reference + French. Translators can copy en.lang to `<code>.lang` and translate the values; no code change needed. - `Makefile` — adds `include/i18n/i18n.c` to both the macOS and the Linux build SOURCE lines. - `minui-presenter.c` — bootstraps i18n right after `GFX_init`, swaps default labels for keys, and re-translates argv-provided labels with a small `MP_RETRANSLATE` macro. ## Compatibility - No-op on systems without the lang files: missing keys fall through to the input literal, so behaviour is identical to today's binary. - Behaviour is identical for paks that pass localised strings already (no matching key → no replacement). - No new dependencies; the hash table and arena are `static` BSS, so the binary grows by ~350 KB of *uninitialised* memory (i.e. not on disk) and the file size delta is just the parser code (~3 KB). ## Test plan - [x] Cross-compiled for `tg5040` via the upstream `savant/minui-toolchain:tg5040` Docker image (same path as CI) - [x] Deployed via ADB to a TrimUI Brick running NextUI v6.11.2 with `language=fr` in `minuisettings.txt` - [x] Gallery pak: bottom-right button now reads "QUITTER" (was "EXIT") - [x] Falls back cleanly to English when `language=en` or no lang files present - [ ] Other platforms: not validated on hardware (identical code path) Companion PRs: - NextUI core i18n + 534 keys: LoveRetro/NextUI#735 - NextUI Updater pak FR: LoveRetro/nextui-updater-pak#18
foXaCe
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May 23, 2026
minui-presenter is shared by many third-party MinUI/NextUI paks (Gallery, Artwork Scraper, Another Cheat Downloader, ...) and the button labels it draws were hard-coded English. With NextUI now shipping an i18n system (see LoveRetro/NextUI#735), the presenter can read the same `language=` setting and localise its labels — both the built-in defaults and the strings passed by paks via --action-text/--cancel-text/... ## What it does - Reads `/mnt/SDCARD/.userdata/shared/minuisettings.txt` once at startup to discover the active language (`language=fr`, `language=en`, ...); falls back to English if the file or the key is missing. - Loads the matching `<code>.lang` file from `/mnt/SDCARD/.system/res/lang/` into a small open-addressed hash table (FNV-1a, 4096 buckets, 256 KB arena). Lookups are ~80 ns on a Cortex-A53. - Replaces the default button text constants (ACTION / SELECT / BACK / OTHER) with `T()` calls using `mp.btn.*` keys. - **Bonus**: after argv parsing, runs the caller-provided button texts through `T()` as well. So a pak that already passes `--cancel-text "EXIT"` doesn't need to change anything — as soon as the lang file contains `EXIT=QUITTER`, the bottom-right button reads "QUITTER" on a French system. ## Files - `include/i18n/i18n.{c,h}` — pure-C i18n core (adapted from the NextUI PR — same parser, same hash table, same fallback semantics). Depends only on `defines.h` (already in the include path via the toolchain's shared common/) for `SDCARD_PATH` and `MAX_PATH`. - `lang/en.lang`, `lang/fr.lang` — reference + French. Translators can copy en.lang to `<code>.lang` and translate the values; no code change needed. - `Makefile` — adds `include/i18n/i18n.c` to both the macOS and the Linux build SOURCE lines. - `minui-presenter.c` — bootstraps i18n right after `GFX_init`, swaps default labels for keys, and re-translates argv-provided labels with a small `MP_RETRANSLATE` macro. ## Compatibility - No-op on systems without the lang files: missing keys fall through to the input literal, so behaviour is identical to today's binary. - Behaviour is identical for paks that pass localised strings already (no matching key → no replacement). - No new dependencies; the hash table and arena are `static` BSS, so the binary grows by ~350 KB of *uninitialised* memory (i.e. not on disk) and the file size delta is just the parser code (~3 KB). ## Test plan - [x] Cross-compiled for `tg5040` via the upstream `savant/minui-toolchain:tg5040` Docker image (same path as CI) - [x] Deployed via ADB to a TrimUI Brick running NextUI v6.11.2 with `language=fr` in `minuisettings.txt` - [x] Gallery pak: bottom-right button now reads "QUITTER" (was "EXIT") - [x] Falls back cleanly to English when `language=en` or no lang files present - [ ] Other platforms: not validated on hardware (identical code path) Companion PRs: - NextUI core i18n + 534 keys: LoveRetro/NextUI#735 - NextUI Updater pak FR: LoveRetro/nextui-updater-pak#18
5 tasks
Adds OK, BACK and two --message strings (No screenshots found, Screenshots directory not found) so paks using minui-presenter for status messages inherit French automatically once the upstream PR lands.
foXaCe
added a commit
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May 23, 2026
minui-presenter is shared by many third-party MinUI/NextUI paks (Gallery, Artwork Scraper, Another Cheat Downloader, ...) and the button labels it draws were hard-coded English. With NextUI now shipping an i18n system (see LoveRetro/NextUI#735), the presenter can read the same `language=` setting and localise its labels — both the built-in defaults and the strings passed by paks via --action-text/--cancel-text/... ## What it does - Reads `/mnt/SDCARD/.userdata/shared/minuisettings.txt` once at startup to discover the active language (`language=fr`, `language=en`, ...); falls back to English if the file or the key is missing. - Loads the matching `<code>.lang` file from `/mnt/SDCARD/.system/res/lang/` into a small open-addressed hash table (FNV-1a, 4096 buckets, 256 KB arena). Lookups are ~80 ns on a Cortex-A53. - Replaces the default button text constants (ACTION / SELECT / BACK / OTHER) with `T()` calls using `mp.btn.*` keys. - **Bonus**: after argv parsing, runs the caller-provided button texts through `T()` as well. So a pak that already passes `--cancel-text "EXIT"` doesn't need to change anything — as soon as the lang file contains `EXIT=QUITTER`, the bottom-right button reads "QUITTER" on a French system. ## Files - `include/i18n/i18n.{c,h}` — pure-C i18n core (adapted from the NextUI PR — same parser, same hash table, same fallback semantics). Depends only on `defines.h` (already in the include path via the toolchain's shared common/) for `SDCARD_PATH` and `MAX_PATH`. - `lang/en.lang`, `lang/fr.lang` — reference + French. Translators can copy en.lang to `<code>.lang` and translate the values; no code change needed. - `Makefile` — adds `include/i18n/i18n.c` to both the macOS and the Linux build SOURCE lines. - `minui-presenter.c` — bootstraps i18n right after `GFX_init`, swaps default labels for keys, and re-translates argv-provided labels with a small `MP_RETRANSLATE` macro. ## Compatibility - No-op on systems without the lang files: missing keys fall through to the input literal, so behaviour is identical to today's binary. - Behaviour is identical for paks that pass localised strings already (no matching key → no replacement). - No new dependencies; the hash table and arena are `static` BSS, so the binary grows by ~350 KB of *uninitialised* memory (i.e. not on disk) and the file size delta is just the parser code (~3 KB). ## Test plan - [x] Cross-compiled for `tg5040` via the upstream `savant/minui-toolchain:tg5040` Docker image (same path as CI) - [x] Deployed via ADB to a TrimUI Brick running NextUI v6.11.2 with `language=fr` in `minuisettings.txt` - [x] Gallery pak: bottom-right button now reads "QUITTER" (was "EXIT") - [x] Falls back cleanly to English when `language=en` or no lang files present - [ ] Other platforms: not validated on hardware (identical code path) Companion PRs: - NextUI core i18n + 534 keys: LoveRetro/NextUI#735 - NextUI Updater pak FR: LoveRetro/nextui-updater-pak#18
The Clock pak hard-coded the YYYY/MM/DD field order in both the rendering and the cursor positioning. Drives this from a new clock.date_order key (YMD/DMY/MDY); en defaults to YMD (ISO), fr uses DMY. The cursor still navigates the logical sequence (year/month/day), just the on-screen positions follow the locale's order. Hour/minute/ second positions are unchanged since the date block keeps the same total width (100 px @1x) regardless of order.
Adds 80 ps.* keys consumed by the companion PR on LoveRetro/nextui-pak-store. Includes button labels, screen titles, settings, info screen, install/uninstall/update flows, storefront categories and the splash text. Companion PR: <pak-store-pr-url>
Adds ~150 sg.* keys consumed by the companion PR on Helaas/nextui-scrapegoat-pak. Covers main menu, library list, ROM detail, queue/progress screens, settings, dialogs, warnings. The parser now decodes \\n / \\t / \\\\ escapes so multi-line dialog strings (cancel-all confirmation, background-scraping warning, ...) can sit on a single .lang line. Existing single-line keys are unaffected. Also localises btn.up_down / btn.left_right (was hardcoded U/D and L/R literals in gametime/bootlogo/battery/ledcontrol) so the button hints render as H/B and G/D in French. New gametime.title_fmt key for the Game Tracker top title. Companion PRs: - Helaas/nextui-scrapegoat-pak#9 - Helaas/Apostrophe#47 (queue widget i18n hook)
Short labels rendered as inline status badges in ScrapeGoat's ROM list (queued / searching / downloading / cloning / matching) and as the type tags (art / cht / pdf). Companion to Helaas/nextui-scrapegoat-pak#9 review fix.
3 tasks
- ~80 ae.* keys for the Aesthetics pak (companion PR pending on redria7/nextui-aesthetics) covering main menu, settings, theme components, decoration browser, dialogs. - 6 ps.* keys for the gabagool download manager footer (Close / Cancel Download / Cancel All Downloads / Show Speed / Hide Speed) + the download title. Consumed by the updated PR on LoveRetro/nextui-pak-store and the gabagool fork BrandonKowalski/gabagool#18 that adds the override hooks.
4 tasks
Adds 30 ae.* keys (15 per locale × 2) for the Aesthetics theme
manager surface that was left untranslated by the initial i18n
pass:
- ae.btn.{details,hide_theme,unhide_theme,trash_it}
- ae.dl.{refresh_catalog,hidden_themes,help_no_entries,help_a,help_x}
- ae.msg.{delete_theme,deleted,delete_failed,error_prefix,
name_exists,theme_renamed,select_one_component,
delete_components,delete_components_failed,
delete_components_done,update_error,updates_done,
download_failed,clear_deco,deleted_path,
delete_path_failed,unsupported_action,delete_deco,
copy_image_to,copy_failed,copy_success}
Covers the download catalog screen (browse / hide / details flow),
the theme delete/rename/copy actions, and the bulk component editor
messages. French translations keep the project's tutoiement style
and reuse the existing terminology choices (« Supprimer », « Échec »,
« Sélectionner », …).
Companion to nextui-scrapegoat-pak commit 1ead06e which routed 9 more ui.c strings through T(). Adds the matching translations here so the runtime can resolve them — without these, T() returns the bare key (e.g. "sg.cheat.fallback_name_fmt") as the visible label. New sg.* keys (149 → 149 EN ↔ FR parity preserved): - sg.cheat.fallback_name_fmt Code %d / Cheat %d - sg.cheat.list_title_fmt Codes triche (%d) / Cheats (%d) - sg.tag.disabled [désactivé] / [disabled] - sg.error.cache_inspect_failed_fmt - sg.error.cache_open_failed_fmt - sg.error.cache_rmdir_failed_fmt - sg.error.cache_unlink_failed_fmt - sg.error.cheat_cache_open_failed_fmt - sg.error.cheat_cache_rmdir_failed_fmt Also rewrites 7 existing FR strings from vouvoiement to tutoiement for style consistency with the rest of the file: - sg.error.queue_active_clear Attendez → Attends - sg.error.cache_cleared_stale Redémarrez → Redémarre - sg.error.bg_start_failed Essayez → Essaie - sg.warn.bg_still_active Fermez/rouvrez → Ferme/rouvre - sg.warn.no_internet Connectez-vous → Connecte-toi - sg.warn.no_credentials allez/ajoutez vos → va/ajoute tes - sg.warn.no_manual_dir Allez/configurez/Il vous faudra → Va/configure/Il te faudra All %s/%d placeholders preserved; encoding UTF-8 clean.
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Summary
Adds a runtime translation layer so all user-facing strings can be localized without restarting the app. English ships as the reference language; French is bundled as a complete second locale (425 keys).
The default behavior is unchanged for existing installs: with no
.langfiles present orlanguage=en, everyT(key)falls back to the literal — which for legacy strings is the original English text → zero regression.Architecture
workspace/all/common/i18n.{c,h}— minimal i18n corekey=value.langfiles (no JSON dependency)T(key)returns the translation, or the input verbatim when no entry matches (safe fallback)I18N_init(code)called fromGFX_init;I18N_reload(code)hot-swaps the table at runtimeskeleton/SYSTEM/res/lang/{en,fr}.lang(425 paired keys)NextUISettings.language[8]persisted inminuisettings.txt(defaults to\"en\"; backward-compatible read)Coverage
All user-visible strings flow through
T():nextui.cminarch/{ma_menu,ma_frontend_opts,ma_saves,ra_integration}.csettings/*.cpp/hpp): Appearance, Display, Audio, System, FN switch, In-Game, RetroAchievements (incl. sync overlay), About, Bluetooth, WiFi, color picker, keyboard promptcommon/api.cbattery,clock,gametime,ledcontrol,minput,bootlogoHot-reload (Settings only)
`Settings → System → Language` switches locale live without exit:
Other apps (launcher, minarch, tools) load the active language on startup — they are short-lived processes relaunched per action, so per-app hot-reload is unnecessary.
Build
`i18n.c` linked into every app that calls `T()`: nextui, minarch, settings, battery, clock, gametime, ledcontrol, minput, bootlogo (9 makefiles updated). Pure C module; safe to include from C++ via the existing `extern "C"` block in `settings/menu.hpp`.
Resource impact:
Compatibility
.langfiles installed — behavior identical to before this PR.lang` into `.system/res/lang/`; auto-discovered by Settings via `discoverLanguages()`Test plan
.lang` and translate valuesNotes
Happy to split this into smaller PRs (core i18n, launcher, settings, tools…) if that's preferred for review.