Add firmware font size setting

Modules/lvgl-module/include/tactility/lvgl_fonts.h

@@ -14,6 +14,15 @@ enum LvglFontSize {
     FONT_SIZE_LARGE,
 };
 
+enum LvglFontScale {
+    FONT_SCALE_SMALL,
+    FONT_SCALE_DEFAULT,
+    FONT_SCALE_LARGE,
+};
+
+void lvgl_set_text_font_scale(enum LvglFontScale font_scale);
+enum LvglFontScale lvgl_get_text_font_scale(void);
+
 const lv_font_t* lvgl_get_shared_icon_font();
 uint32_t lvgl_get_shared_icon_font_height();
 

Modules/lvgl-module/source/lvgl_fonts.c

@@ -13,8 +13,30 @@ extern const lv_font_t TT_LVGL_LAUNCHER_FONT_ICON_SYMBOL;
 extern const lv_font_t TT_LVGL_STATUSBAR_FONT_ICON_SYMBOL;
 extern const lv_font_t TT_LVGL_SHARED_FONT_ICON_SYMBOL;
 
+static enum LvglFontScale text_font_scale = FONT_SCALE_DEFAULT;
+
+void lvgl_set_text_font_scale(enum LvglFontScale font_scale) {
+    check(font_scale >= FONT_SCALE_SMALL && font_scale <= FONT_SCALE_LARGE);
+    text_font_scale = font_scale;
+}
+
+enum LvglFontScale lvgl_get_text_font_scale(void) {
+    return text_font_scale;
+}
+
+static enum LvglFontSize resolve_text_font_size(enum LvglFontSize font_size) {
+    int resolved = (int)font_size + (int)text_font_scale - (int)FONT_SCALE_DEFAULT;
+    if (resolved < FONT_SIZE_SMALL) {
+        return FONT_SIZE_SMALL;
+    }
+    if (resolved > FONT_SIZE_LARGE) {
+        return FONT_SIZE_LARGE;
+    }
+    return (enum LvglFontSize)resolved;
+}
+
 uint32_t lvgl_get_text_font_height(enum LvglFontSize font_size) {
-    switch (font_size) {
+    switch (resolve_text_font_size(font_size)) {
         case FONT_SIZE_SMALL: return TT_LVGL_TEXT_FONT_SMALL_SIZE;
         case FONT_SIZE_DEFAULT: return TT_LVGL_TEXT_FONT_DEFAULT_SIZE;
         case FONT_SIZE_LARGE: return TT_LVGL_TEXT_FONT_LARGE_SIZE;
@@ -22,7 +44,7 @@ uint32_t lvgl_get_text_font_height(enum LvglFontSize font_size) {
     }
 }
 const lv_font_t* lvgl_get_text_font(enum LvglFontSize font_size) {
-    switch (font_size) {
+    switch (resolve_text_font_size(font_size)) {
         case FONT_SIZE_SMALL: return &TT_LVGL_TEXT_FONT_SMALL_SYMBOL;
         case FONT_SIZE_DEFAULT: return &TT_LVGL_TEXT_FONT_DEFAULT_SYMBOL;
         case FONT_SIZE_LARGE: return &TT_LVGL_TEXT_FONT_LARGE_SYMBOL;

Modules/lvgl-module/source/symbols.c

@@ -13,6 +13,8 @@ const struct ModuleSymbol lvgl_module_symbols[] = {
     DEFINE_MODULE_SYMBOL(lvgl_is_running),
     DEFINE_MODULE_SYMBOL(lvgl_get_ui_density),
     // lvgl_fonts
+    DEFINE_MODULE_SYMBOL(lvgl_set_text_font_scale),
+    DEFINE_MODULE_SYMBOL(lvgl_get_text_font_scale),
     DEFINE_MODULE_SYMBOL(lvgl_get_shared_icon_font),
     DEFINE_MODULE_SYMBOL(lvgl_get_shared_icon_font_height),
     DEFINE_MODULE_SYMBOL(lvgl_get_text_font),

Tactility/Include/Tactility/lvgl/Lvgl.h

@@ -1,5 +1,9 @@
 #pragma once
 
+namespace tt::settings::display {
+enum class FontSize;
+}
+
 namespace tt::lvgl {
 
 #ifdef ESP_PLATFORM
@@ -12,6 +16,9 @@ static constexpr auto* PATH_PREFIX = "A:/";
 
 bool isStarted();
 
+/** Applies the selected semantic text size to the LVGL theme and future widgets. */
+void applyFontSize(settings::display::FontSize fontSize);
+
 void start();
 
 void stop();

Tactility/Include/Tactility/settings/DisplaySettings.h

@@ -22,8 +22,16 @@ enum class ScreensaverType {
     Count           // Sentinel for bounds checking - must be last
 };
 
+enum class FontSize {
+    Small,
+    Default,
+    Large,
+    Count
+};
+
 struct DisplaySettings {
     Orientation orientation;
+    FontSize fontSize = FontSize::Default;
     uint8_t gammaCurve;
     uint8_t backlightDuty;
     bool backlightTimeoutEnabled;

Tactility/Source/app/display/Display.cpp

@@ -8,6 +8,7 @@
 
 #include <Tactility/app/App.h>
 #include <Tactility/hal/display/DisplayDevice.h>
+#include <Tactility/lvgl/Lvgl.h>
 #include <Tactility/lvgl/Toolbar.h>
 #include <Tactility/settings/DisplaySettings.h>
 
@@ -74,6 +75,21 @@ class HalDisplayApp final : public App {
         }
     }
 
+    static void onFontSizeChanged(lv_event_t* event) {
+        auto* app = static_cast<HalDisplayApp*>(lv_event_get_user_data(event));
+        auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
+        uint32_t selected_index = lv_dropdown_get_selected(dropdown);
+        if (selected_index >= static_cast<uint32_t>(settings::display::FontSize::Count)) {
+            return;
+        }
+        auto selected_size = static_cast<settings::display::FontSize>(selected_index);
+        if (selected_size != app->displaySettings.fontSize) {
+            app->displaySettings.fontSize = selected_size;
+            app->displaySettingsUpdated = true;
+            lvgl::applyFontSize(selected_size);
+        }
+    }
+
     static void onDisableWhenChargingChanged(lv_event_t* event) {
         auto* app = static_cast<HalDisplayApp*>(lv_event_get_user_data(event));
         auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
@@ -224,6 +240,23 @@ public:
         // Set the dropdown to match current orientation enum
         lv_dropdown_set_selected(orientation_dropdown, static_cast<uint16_t>(displaySettings.orientation));
 
+        // Font size
+
+        auto* font_size_wrapper = lv_obj_create(main_wrapper);
+        lv_obj_set_size(font_size_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+        lv_obj_set_style_pad_all(font_size_wrapper, 0, LV_STATE_DEFAULT);
+        lv_obj_set_style_border_width(font_size_wrapper, 0, LV_STATE_DEFAULT);
+
+        auto* font_size_label = lv_label_create(font_size_wrapper);
+        lv_label_set_text(font_size_label, "Font size");
+        lv_obj_align(font_size_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+        auto* font_size_dropdown = lv_dropdown_create(font_size_wrapper);
+        lv_dropdown_set_options(font_size_dropdown, "Small\nDefault\nLarge");
+        lv_obj_align(font_size_dropdown, LV_ALIGN_RIGHT_MID, 0, 0);
+        lv_obj_add_event_cb(font_size_dropdown, onFontSizeChanged, LV_EVENT_VALUE_CHANGED, this);
+        lv_dropdown_set_selected(font_size_dropdown, static_cast<uint16_t>(displaySettings.fontSize));
+
         // Screen timeout
 
         if (hal_display->supportsBacklightDuty()) {

Tactility/Source/app/kerneldisplay/KernelDisplay.cpp

@@ -11,6 +11,7 @@
 #include <Tactility/service/displayidle/DisplayIdleService.h>
 #endif
 #include <Tactility/app/App.h>
+#include <Tactility/lvgl/Lvgl.h>
 #include <Tactility/lvgl/Toolbar.h>
 #include <Tactility/settings/DisplaySettings.h>
 
@@ -69,6 +70,21 @@ class KernelDisplayApp final : public App {
         }
     }
 
+    static void onFontSizeChanged(lv_event_t* event) {
+        auto* app = static_cast<KernelDisplayApp*>(lv_event_get_user_data(event));
+        auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
+        uint32_t selected_index = lv_dropdown_get_selected(dropdown);
+        if (selected_index >= static_cast<uint32_t>(settings::display::FontSize::Count)) {
+            return;
+        }
+        auto selected_size = static_cast<settings::display::FontSize>(selected_index);
+        if (selected_size != app->displaySettings.fontSize) {
+            app->displaySettings.fontSize = selected_size;
+            app->displaySettingsUpdated = true;
+            lvgl::applyFontSize(selected_size);
+        }
+    }
+
     static void onTimeoutSwitch(lv_event_t* event) {
         auto* app = static_cast<KernelDisplayApp*>(lv_event_get_user_data(event));
         auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
@@ -183,6 +199,23 @@ public:
         // Set the dropdown to match current orientation enum
         lv_dropdown_set_selected(orientation_dropdown, static_cast<uint16_t>(displaySettings.orientation));
 
+        // Font size
+
+        auto* font_size_wrapper = lv_obj_create(main_wrapper);
+        lv_obj_set_size(font_size_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+        lv_obj_set_style_pad_all(font_size_wrapper, 0, LV_STATE_DEFAULT);
+        lv_obj_set_style_border_width(font_size_wrapper, 0, LV_STATE_DEFAULT);
+
+        auto* font_size_label = lv_label_create(font_size_wrapper);
+        lv_label_set_text(font_size_label, "Font size");
+        lv_obj_align(font_size_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+        auto* font_size_dropdown = lv_dropdown_create(font_size_wrapper);
+        lv_dropdown_set_options(font_size_dropdown, "Small\nDefault\nLarge");
+        lv_obj_align(font_size_dropdown, LV_ALIGN_RIGHT_MID, 0, 0);
+        lv_obj_add_event_cb(font_size_dropdown, onFontSizeChanged, LV_EVENT_VALUE_CHANGED, this);
+        lv_dropdown_set_selected(font_size_dropdown, static_cast<uint16_t>(displaySettings.fontSize));
+
         // Screen timeout
         // Note: DisplayIdleService doesn't act on these settings for kernel-driver displays yet
         // (it only looks up the deprecated tt::hal::display::DisplayDevice), so these currently

Tactility/Source/lvgl/Lvgl.cpp

@@ -13,6 +13,7 @@
 #include <tactility/device.h>
 #include <tactility/drivers/backlight.h>
 #include <tactility/log.h>
+#include <tactility/lvgl_fonts.h>
 #include <tactility/lvgl_module.h>
 #include <tactility/lvgl_pointer.h>
 #include <tactility/module.h>
@@ -27,6 +28,49 @@ bool isStarted() {
     return module_is_started(&lvgl_module);
 }
 
+void applyFontSize(settings::display::FontSize fontSize) {
+    LvglFontScale scale;
+    switch (fontSize) {
+        using enum settings::display::FontSize;
+        case Small:
+            scale = FONT_SCALE_SMALL;
+            break;
+        case Large:
+            scale = FONT_SCALE_LARGE;
+            break;
+        case Default:
+        default:
+            scale = FONT_SCALE_DEFAULT;
+            break;
+    }
+
+    lvgl_set_text_font_scale(scale);
+    const lv_font_t* font = lvgl_get_text_font(FONT_SIZE_DEFAULT);
+
+    for (lv_display_t* display = lv_display_get_next(nullptr);
+         display != nullptr;
+         display = lv_display_get_next(display)) {
+#if LV_USE_THEME_DEFAULT
+        if (lv_display_get_theme(display) == lv_theme_default_get()) {
+            lv_obj_t* screen = lv_display_get_screen_active(display);
+            lv_theme_default_init(
+                display,
+                lv_theme_get_color_primary(screen),
+                lv_theme_get_color_secondary(screen),
+                LV_THEME_DEFAULT_DARK,
+                font
+            );
+        }
+#endif
+        // The display layers are independent inheritance roots. Updating all of them makes
+        // the new size visible immediately in regular screens, overlays, and the status bar.
+        lv_obj_set_style_text_font(lv_display_get_screen_active(display), font, LV_PART_MAIN);
+        lv_obj_set_style_text_font(lv_display_get_layer_top(display), font, LV_PART_MAIN);
+        lv_obj_set_style_text_font(lv_display_get_layer_sys(display), font, LV_PART_MAIN);
+        lv_obj_set_style_text_font(lv_display_get_layer_bottom(display), font, LV_PART_MAIN);
+    }
+}
+
 void attachDevices() {
     LOG_I(TAG, "Adding devices");
 
@@ -55,6 +99,7 @@ void attachDevices() {
         if (rotation != lv_display_get_rotation(primary_lvgl_display)) {
             lv_display_set_rotation(primary_lvgl_display, rotation);
         }
+        applyFontSize(settings.fontSize);
     }
 
     // Start touch

Tactility/Source/settings/DisplaySettings.cpp

@@ -17,6 +17,7 @@ static std::string getSettingsFilePath() {
 }
 
 constexpr auto* SETTINGS_KEY_ORIENTATION = "orientation";
+constexpr auto* SETTINGS_KEY_FONT_SIZE = "fontSize";
 constexpr auto* SETTINGS_KEY_GAMMA_CURVE = "gammaCurve";
 constexpr auto* SETTINGS_KEY_BACKLIGHT_DUTY = "backlightDuty";
 constexpr auto* SETTINGS_KEY_TIMEOUT_ENABLED = "backlightTimeoutEnabled";
@@ -71,6 +72,34 @@ static bool fromString(const std::string& str, Orientation& orientation) {
     }
 }
 
+static std::string toString(FontSize font_size) {
+    switch (font_size) {
+        using enum FontSize;
+        case Small:
+            return "Small";
+        case Default:
+            return "Default";
+        case Large:
+            return "Large";
+        default:
+            std::unreachable();
+    }
+}
+
+static bool fromString(const std::string& str, FontSize& font_size) {
+    if (str == "Small") {
+        font_size = FontSize::Small;
+        return true;
+    } else if (str == "Default") {
+        font_size = FontSize::Default;
+        return true;
+    } else if (str == "Large") {
+        font_size = FontSize::Large;
+        return true;
+    }
+    return false;
+}
+
 static std::string toString(ScreensaverType type) {
     switch (type) {
         using enum ScreensaverType;
@@ -132,6 +161,12 @@ bool load(DisplaySettings& settings) {
         orientation = getDefaultOrientation();
     }
 
+    auto font_size_entry = map.find(SETTINGS_KEY_FONT_SIZE);
+    FontSize font_size = FontSize::Default;
+    if (font_size_entry != map.end()) {
+        fromString(font_size_entry->second, font_size);
+    }
+
     auto gamma_entry = map.find(SETTINGS_KEY_GAMMA_CURVE);
     int gamma_curve = 0;
     if (gamma_entry != map.end()) {
@@ -172,6 +207,7 @@ bool load(DisplaySettings& settings) {
     }
 
     settings.orientation = orientation;
+    settings.fontSize = font_size;
     settings.gammaCurve = gamma_curve;
     settings.backlightDuty = backlight_duty;
     settings.backlightTimeoutEnabled = timeout_enabled;
@@ -185,6 +221,7 @@ bool load(DisplaySettings& settings) {
 DisplaySettings getDefault() {
     return DisplaySettings {
         .orientation = getDefaultOrientation(),
+        .fontSize = FontSize::Default,
         .gammaCurve = 1,
         .backlightDuty = 200,
         .backlightTimeoutEnabled = false,
@@ -207,6 +244,7 @@ bool save(const DisplaySettings& settings) {
     map[SETTINGS_KEY_BACKLIGHT_DUTY] = std::to_string(settings.backlightDuty);
     map[SETTINGS_KEY_GAMMA_CURVE] = std::to_string(settings.gammaCurve);
     map[SETTINGS_KEY_ORIENTATION] = toString(settings.orientation);
+    map[SETTINGS_KEY_FONT_SIZE] = toString(settings.fontSize);
     map[SETTINGS_KEY_TIMEOUT_ENABLED] = settings.backlightTimeoutEnabled ? "1" : "0";
     map[SETTINGS_KEY_TIMEOUT_MS] = std::to_string(settings.backlightTimeoutMs);
     map[SETTINGS_KEY_SCREENSAVER_TYPE] = toString(settings.screensaverType);