feat(ui): boot / loading splash at startup

CHANGELOG.md

@@ -5,6 +5,18 @@ All notable, behaviour-affecting changes land here. Format follows
 uses lightweight semantic-ish versioning (bumped on any user-visible
 change, not on every commit).
 
+## v0.29.9 — 2026-06
+
+### Added
+
+- **Boot / "loading" splash.** On power-up the device now shows a "Bamboard"
+  splash — a spinner over a status line that walks the boot phases (Connecting
+  to Wi-Fi… → Checking for updates… → Connecting to Bambuddy…) — instead of a
+  frozen, data-less dashboard during the ~20-30 s it takes to join Wi-Fi, run
+  the boot-time OTA check and pull the first data. It dismisses itself the
+  moment printer data arrives, or after a 25 s grace period so an unreachable
+  Bambuddy can't pin it. All five UI languages.
+
 ## v0.29.8 — 2026-06
 
 ### Fixed

firmware/src/config.h

@@ -87,6 +87,11 @@ constexpr uint32_t DIM_AFTER_MS = 60UL * 1000UL;
 // Ambient idle clock: floats over the current screen once the panel has been
 // untouched this long AND the whole farm is quiet (nothing printing/faulted).
 constexpr uint32_t AMBIENT_AFTER_MS = 45UL * 1000UL;
+
+// Boot "loading" splash: the longest it stays up before giving way to the
+// (possibly offline) dashboard, so an unreachable Bambuddy can't pin it forever.
+// Covers the worst case: Wi-Fi connect (~15 s) + boot-time OTA check (~8 s).
+constexpr uint32_t BOOT_SPLASH_MAX_MS = 25UL * 1000UL;
 constexpr uint8_t  BL_FULL = 255;
 constexpr uint8_t  BL_DIM  = 40;
 

firmware/src/main.cpp

@@ -967,6 +967,8 @@ void setup() {
     // current / GitHub down all fall through quickly so the device still
     // boots. Dev-sentinel builds skip it so a USB-flashed work-in-progress
     // isn't immediately pulled back to the published release.
+    ui::screens::boot_overlay_set_status(::i18n::tr(::i18n::Str::BOOT_UPDATE));
+    lv_timer_handler();
 #if BAMBOARD_OTA_AUTOCHECK
     if (!BAMBOARD_VERSION_IS_DEV) {
         run_boot_update();
@@ -978,6 +980,11 @@ void setup() {
     bambuddy::g_client.begin(g_cfg_bambuddy_url, g_cfg_api_key,
                              g_cfg_cf_id, g_cfg_cf_secret);
 
+    // Final boot phase: the net task (started just below) reaches Bambuddy. Show
+    // it on the splash; the UI manager dismisses the splash once data lands.
+    ui::screens::boot_overlay_set_status(::i18n::tr(::i18n::Str::BOOT_CONNECT));
+    lv_timer_handler();
+
     // Arm the task watchdog (10 s, panic+reboot on timeout) before the UI task
     // subscribes itself. Best-effort: if the Arduino runtime already initialised
     // the TWDT this is a no-op and the existing timeout stands — the UI loop

firmware/src/ui/i18n.cpp

@@ -109,6 +109,10 @@ static const char* const T[][(int)Lang::COUNT] = {
     /*CONFIRM_REMOVE*/{"Tap again to remove (3 s)", "Toca otra vez para quitar (3 s)", "Touchez encore pour retirer (3 s)", "Toque novamente p/ remover (3 s)", "Nochmal zum Entfernen (3 s)"},
     /*AMBIENT_ALL_IDLE*/ {"All idle", "Todo inactivo", "Tout au repos", "Tudo parado", "Alles im Leerlauf"},
     /*AMBIENT_NEXT*/  {"Next", "Siguiente", "Suivant", "Próximo", "Nächste"},
+    // -- boot splash --
+    /*BOOT_WIFI*/     {"Connecting to Wi-Fi...", "Conectando al Wi-Fi...", "Connexion au Wi-Fi...", "A ligar ao Wi-Fi...", "Verbinde mit WLAN..."},
+    /*BOOT_UPDATE*/   {"Checking for updates...", "Buscando actualizaciones...", "Recherche de mises à jour...", "A procurar atualizações...", "Suche nach Updates..."},
+    /*BOOT_CONNECT*/  {"Connecting to Bambuddy...", "Conectando a Bambuddy...", "Connexion à Bambuddy...", "A ligar ao Bambuddy...", "Verbinde mit Bambuddy..."},
 };
 
 static_assert(sizeof(T) / sizeof(T[0]) == (size_t)Str::_COUNT,

firmware/src/ui/i18n.h

@@ -56,6 +56,8 @@ enum class Str : uint16_t {
     QUEUE_EMPTY, QUEUE_POS, QUEUE_REMOVED, QUEUE_REMOVE_FAILED, CONFIRM_REMOVE,
     // ambient idle clock
     AMBIENT_ALL_IDLE, AMBIENT_NEXT,
+    // boot splash status
+    BOOT_WIFI, BOOT_UPDATE, BOOT_CONNECT,
     _COUNT
 };
 

firmware/src/ui/screens.h

@@ -77,6 +77,16 @@ void      ota_set_error   (const char* msg);
 void      ota_apply       ();
 bool      ota_is_active   ();
 
+// Full-screen boot / "loading" splash — the Bamboard wordmark, a spinner and a
+// status line. Built visible at startup and dismissed by the UI manager once
+// the device has printer data (or after BOOT_SPLASH_MAX_MS), so the user sees a
+// clear "starting up" screen instead of a frozen, dataless dashboard.
+// boot_overlay_set_status() is UI/setup-task only (called during boot phases).
+lv_obj_t* build_boot_overlay(lv_obj_t* parent);
+void      boot_overlay_set_status(const char* msg);
+void      boot_overlay_hide();
+bool      boot_overlay_is_visible();
+
 // Full-screen camera snapshot overlay. Opened by tapping the dashboard
 // progress ring; while it's open the net task fetches + decodes JPEG frames
 // (camera_decode_frame, called ON the net task), camera_apply() (UI task)

firmware/src/ui/screens/overlays.cpp

@@ -850,4 +850,70 @@ void temp_graph_close() {
 }
 bool temp_graph_is_open() { return s_tg_open; }
 
+// ---------------------------------------------------------------------------
+// Boot / "loading" splash
+// ---------------------------------------------------------------------------
+//
+// Full-screen overlay shown from power-on while Wi-Fi connects, the boot-time
+// OTA check runs and the first Bambuddy data arrives — so the user sees an
+// obvious "starting up" screen (brand wordmark + spinner + a per-phase status
+// line) instead of a frozen, data-less dashboard. Built LAST in
+// ui::Manager::begin() so it z-orders above everything and — unlike the other
+// overlays — starts VISIBLE. ui::Manager::refresh() calls boot_overlay_hide()
+// once a printer snapshot lands (or BOOT_SPLASH_MAX_MS elapses).
+
+static lv_obj_t* s_boot_overlay = nullptr;
+static lv_obj_t* s_boot_status  = nullptr;
+
+lv_obj_t* build_boot_overlay(lv_obj_t* parent) {
+    ensure_styles();
+    s_boot_overlay = lv_obj_create(parent);
+    lv_obj_remove_style_all(s_boot_overlay);
+    lv_obj_set_size(s_boot_overlay, LV_HOR_RES, LV_VER_RES);
+    lv_obj_align(s_boot_overlay, LV_ALIGN_TOP_LEFT, 0, 0);
+    lv_obj_set_style_bg_color(s_boot_overlay, lv_color_hex(::ui::C_BG), 0);
+    lv_obj_set_style_bg_opa(s_boot_overlay, LV_OPA_COVER, 0);
+    lv_obj_clear_flag(s_boot_overlay, LV_OBJ_FLAG_SCROLLABLE);
+
+    // Brand wordmark — "board" recoloured in accent, same as the header.
+    lv_obj_t* mark = lv_label_create(s_boot_overlay);
+    lv_label_set_recolor(mark, true);
+    lv_label_set_text(mark, "Bam#00B7C3 board#");
+    lv_obj_set_style_text_font(mark, &bb_font_36, 0);
+    lv_obj_set_style_text_color(mark, lv_color_hex(::ui::C_TEXT), 0);
+    lv_obj_align(mark, LV_ALIGN_CENTER, 0, -44);
+
+    // Spinner — advances whenever lv_timer_handler() runs (the Wi-Fi-connect
+    // wait and once the UI task is up; it pauses during the single blocking
+    // OTA-check call, which the status line covers).
+    lv_obj_t* spin = lv_spinner_create(s_boot_overlay, 1000, 60);
+    lv_obj_set_size(spin, 46, 46);
+    lv_obj_align(spin, LV_ALIGN_CENTER, 0, 16);
+    lv_obj_set_style_arc_color(spin, lv_color_hex(::ui::C_PANEL_HI), LV_PART_MAIN);
+    lv_obj_set_style_arc_width(spin, 5, LV_PART_MAIN);
+    lv_obj_set_style_arc_color(spin, lv_color_hex(::ui::C_ACCENT), LV_PART_INDICATOR);
+    lv_obj_set_style_arc_width(spin, 5, LV_PART_INDICATOR);
+
+    s_boot_status = lv_label_create(s_boot_overlay);
+    lv_label_set_text(s_boot_status, i18n::tr(i18n::Str::BOOT_WIFI));
+    lv_obj_set_style_text_font(s_boot_status, &bb_font_14, 0);
+    lv_obj_set_style_text_color(s_boot_status, lv_color_hex(::ui::C_TEXT_DIM), 0);
+    lv_obj_align(s_boot_status, LV_ALIGN_CENTER, 0, 70);
+
+    // Starts visible (no HIDDEN flag) — it's the power-on state.
+    return s_boot_overlay;
+}
+
+void boot_overlay_set_status(const char* msg) {
+    if (s_boot_status && msg) lv_label_set_text(s_boot_status, msg);
+}
+
+void boot_overlay_hide() {
+    if (s_boot_overlay) lv_obj_add_flag(s_boot_overlay, LV_OBJ_FLAG_HIDDEN);
+}
+
+bool boot_overlay_is_visible() {
+    return s_boot_overlay && !lv_obj_has_flag(s_boot_overlay, LV_OBJ_FLAG_HIDDEN);
+}
+
 }  // namespace ui::screens

firmware/src/ui/ui.cpp

@@ -83,6 +83,10 @@ void Manager::begin() {
     // Live temperature graph — likewise a hidden overlay floated on demand.
     screens::build_temp_graph_overlay(s_root);
 
+    // Boot / "loading" splash — built LAST so it covers every screen + overlay,
+    // and (uniquely) starts VISIBLE. refresh() dismisses it once data lands.
+    screens::build_boot_overlay(s_root);
+
     // Show the initial screen directly. We can't use go_to() here: current_
     // already starts at Dashboard, so go_to(Dashboard) would early-return on
     // its `s == current_` guard and leave the screen hidden (the loop above
@@ -137,6 +141,14 @@ void Manager::refresh() {
         selected_printer_id_ = ps[0].id;
     }
 
+    // Dismiss the boot/loading splash once we have printer data (or after a
+    // grace period, so an unreachable Bambuddy can't pin it) — revealing the
+    // dashboard underneath instead of a frozen, data-less screen.
+    if (screens::boot_overlay_is_visible() &&
+        (n > 0 || millis() > ::display::BOOT_SPLASH_MAX_MS)) {
+        screens::boot_overlay_hide();
+    }
+
     // Fire a one-shot toast when any printer leaves a printing state for
     // Finish (✓) or Failed/Error. Skipped on the first sight of a printer
     // (no known previous state) so an already-finished job doesn't toast at boot.

sim/lv_conf.h

@@ -66,7 +66,9 @@
 #define LV_USE_MSGBOX     0
 #define LV_USE_SPAN       0
 #define LV_USE_SPINBOX    0
-#define LV_USE_SPINNER    0
+/* SPINNER on: the boot/loading splash (overlays.cpp build_boot_overlay) uses
+   lv_spinner; the firmware lv_conf enables it too. Depends on LV_USE_ARC (above). */
+#define LV_USE_SPINNER    1
 #define LV_USE_TABVIEW    0
 #define LV_USE_TILEVIEW   0
 #define LV_USE_WIN        0

sim/main.cpp

@@ -89,6 +89,13 @@ static void render_fixtures(const std::string& out) {
     auto& C = bambuddy::g_client;
     JsonDocument d;
 
+    // Boot / "loading" splash — rendered before any data is injected, so the
+    // overlay (built visible in ui::Manager::begin) is still up. Draw it with
+    // lv_timer_handler() directly, NOT pump(): pump() calls ui.refresh(), whose
+    // hide logic would dismiss the splash the moment it sees no printers.
+    lv_timer_handler(); lv_timer_handler();
+    dump_png(out, "boot");
+
     // A small farm: #1 (focused) mid-print with a chained AMS — first unit
     // drying; #2 also printing; #3 idle.
     demo_status(1,