Add font reloading button.

Penumbra/Interop/FontReloader.cs

@@ -0,0 +1,56 @@
+using Dalamud.Logging;
+using FFXIVClientStructs.FFXIV.Client.System.Framework;
+using FFXIVClientStructs.FFXIV.Component.GUI;
+
+namespace Penumbra.Interop;
+
+// Handle font reloading via 
+public static unsafe class FontReloader
+{
+    private static readonly AtkModule*                                        AtkModule       = null;
+    private static readonly delegate* unmanaged<AtkModule*, bool, bool, void> ReloadFontsFunc = null;
+
+    public static bool Valid
+        => ReloadFontsFunc != null;
+
+    public static void Reload()
+    {
+        if( Valid )
+        {
+            ReloadFontsFunc( AtkModule, false, true ); 
+        }
+        else
+        {
+            PluginLog.Error( "Could not reload fonts, function could not be found." );
+        }
+    }
+
+    static FontReloader()
+    {
+        if( ReloadFontsFunc != null )
+        {
+            return;
+        }
+
+        var framework = Framework.Instance();
+        if( framework == null )
+        {
+            return;
+        }
+
+        var uiModule = framework->GetUiModule();
+        if( uiModule == null )
+        {
+            return;
+        }
+
+        var atkModule = uiModule->GetRaptureAtkModule();
+        if( atkModule == null )
+        {
+            return;
+        }
+
+        AtkModule       = &atkModule->AtkModule;
+        ReloadFontsFunc = ( ( delegate* unmanaged< AtkModule*, bool, bool, void >* )AtkModule->vtbl )[ 43 ];
+    }
+}

Penumbra/UI/ConfigWindow.SettingsTab.Advanced.cs

@@ -1,8 +1,10 @@
+using System.Numerics;
 using Dalamud.Interface;
 using ImGuiNET;
 using OtterGui;
 using OtterGui.Raii;
 using Penumbra.GameData.ByteString;
+using Penumbra.Interop;
 using Penumbra.UI.Classes;
 
 namespace Penumbra.UI;
@@ -24,6 +26,7 @@ public partial class ConfigWindow
             DrawEnableDebugModeBox();
             DrawEnableFullResourceLoggingBox();
             DrawReloadResourceButton();
+            DrawReloadFontsButton();
             ImGui.NewLine();
         }
 
@@ -168,5 +171,13 @@ public partial class ConfigWindow
             ImGuiUtil.HoverTooltip( "Reload some specific files that the game keeps in memory at all times.\n"
               + "You usually should not need to do this." );
         }
+
+        private static void DrawReloadFontsButton()
+        {
+            if( ImGuiUtil.DrawDisabledButton( "Reload Fonts", Vector2.Zero, "Force the game to reload its font files.", !FontReloader.Valid ) )
+            {
+                FontReloader.Reload();
+            }
+        }
     }
 }