Add setting for UI scale (#2326)

src/dusk/settings.cpp

@@ -1,6 +1,7 @@
 #include "dusk/settings.h"
 #include <aurora/aurora.h>
 #include "dusk/config.hpp"
+#include "dusk/ui/ui.hpp"
 #include "dusk/game_mode.hpp"
 
 namespace dusk {
@@ -16,6 +17,7 @@ UserSettings g_userSettings = {
         .rememberWindowSize {"video.rememberWindowSize", false},
         .lastWindowWidth {"video.lastWindowWidth", 0},
         .lastWindowHeight {"video.lastWindowHeight", 0},
+        .uiScale {"video.uiScale", 100},
     },
 
     .audio = {
@@ -228,6 +230,8 @@ void registerSettings() {
     Register(g_userSettings.video.rememberWindowSize);
     Register(g_userSettings.video.lastWindowWidth);
     Register(g_userSettings.video.lastWindowHeight);
+    Register(g_userSettings.video.uiScale, 
+        [](const int&, const int&) { dusk::ui::apply_scale(); });
 
     // Audio
     Register(g_userSettings.audio.masterVolume);

src/dusk/settings.h

@@ -145,6 +145,7 @@ struct UserSettings {
         ConfigVar<bool> rememberWindowSize;
         ConfigVar<int> lastWindowWidth;
         ConfigVar<int> lastWindowHeight;
+        ConfigVar<int> uiScale;
     } video;
 
     struct {

src/dusk/ui/settings.cpp

@@ -770,6 +770,12 @@ SettingsWindow::SettingsWindow(bool prelaunch) : mPrelaunch(prelaunch) {
                     },
                 .isDisabled = [] { return IsMobile; },
             });
+
+        config_int_select(leftPane, rightPane, getSettings().video.uiScale,
+            "UI Scale", 
+            "Scales the Dusklight interface relative to the display's DPI scale. Has no effect on the game's UI and HUD.",
+            50, 200, 25, {}, {}, "%");
+
         leftPane.add_section("Resolution");
         graphics_tuner_control(*this, leftPane, rightPane,
             getSettings().game.internalResolutionScale,

src/dusk/ui/ui.cpp

@@ -214,6 +214,8 @@ void handle_event(const SDL_Event& event) noexcept {
             });
         }
         sConnectedGamepads.erase(event.gdevice.which);
+    } else if (event.type == SDL_EVENT_WINDOW_DISPLAY_SCALE_CHANGED) {
+        apply_scale();
     }
     input::handle_event(event);
 }
@@ -491,4 +493,14 @@ bool consume_menu_notification_request() noexcept {
     return requested;
 }
 
+void apply_scale() noexcept {
+    const auto userScale = getSettings().video.uiScale.getValue();
+    auto scale = 0.0f;
+    if (userScale != 0) {
+        const auto displayScale = aurora::window::get_window_size().scale;
+        scale = static_cast<float>(userScale) / 100.0f * (displayScale > 0.0f ? displayScale : 1.0f);
+    }
+    aurora::rmlui::set_ui_scale(scale);
+}
+
 }  // namespace dusk::ui

src/dusk/ui/ui.hpp

@@ -114,4 +114,6 @@ bool consume_menu_notification_request() noexcept;
 const char* battery_icon(SDL_PowerState state, int level) noexcept;
 const char* connection_state_icon(SDL_JoystickConnectionState state) noexcept;
 
+void apply_scale() noexcept;
+
 }  // namespace dusk::ui

src/m_Do/m_Do_main.cpp

@@ -776,6 +776,7 @@ int game_main(int argc, char* argv[]) {
 
     dusk::texture_replacements::reload();
     dusk::ui::initialize();
+    dusk::ui::apply_scale();
     dusk::ui::push_document(std::make_unique<dusk::ui::Overlay>(), true, true);
     dusk::ui::push_document(std::make_unique<dusk::ui::TouchControls>(), false, true);
     dusk::ui::push_document(std::make_unique<dusk::ui::MenuBar>(), false);