5 files changed, 10 insertions, 10 deletions
diff --git a/functions.h b/functions.h
index 39cbb5dfb..3395961a7 100644
--- a/functions.h
+++ b/functions.h
@@ -191,9 +191,9 @@ uint ConvertIntDate(uint date);
 /* misc functions */
 void MarkTileDirty(int x, int y);
 void MarkTileDirtyByTile(TileIndex tile);
-void InvalidateWindow(byte cls, WindowNumber number);
-void InvalidateWindowWidget(byte cls, WindowNumber number, byte widget_index);
-void InvalidateWindowClasses(byte cls);
+void InvalidateWindow(WindowClass cls, WindowNumber number);
+void InvalidateWindowWidget(WindowClass cls, WindowNumber number, byte widget_index);
+void InvalidateWindowClasses(WindowClass cls);
 void DeleteWindowById(WindowClass cls, WindowNumber number);
 void DeleteWindowByClass(WindowClass cls);
 
diff --git a/gui.h b/gui.h
index 3a5938a0b..7a4d4f4d8 100644
--- a/gui.h
+++ b/gui.h
@@ -126,7 +126,7 @@ extern const byte _fios_colors[];
 
 /* network gui */
 void ShowNetworkGameWindow(void);
-void ShowChatWindow(StringID str, StringID caption, int maxlen, int maxwidth, byte window_class, uint16 window_number);
+void ShowChatWindow(StringID str, StringID caption, int maxlen, int maxwidth, WindowClass window_class, WindowNumber window_number);
 
 /* bridge_gui.c */
 void ShowBuildBridgeWindow(uint start, uint end, byte type);
diff --git a/network_gui.c b/network_gui.c
index 5c755dbd2..e63811fcd 100644
--- a/network_gui.c
+++ b/network_gui.c
@@ -1397,7 +1397,7 @@ static const WindowDesc _chat_window_desc = {
 	ChatWindowWndProc
 };
 
-void ShowChatWindow(StringID str, StringID caption, int maxlen, int maxwidth, byte window_class, uint16 window_number)
+void ShowChatWindow(StringID str, StringID caption, int maxlen, int maxwidth, WindowClass window_class, WindowNumber window_number)
 {
 	Window *w;
 
diff --git a/window.c b/window.c
index 3398081a8..f87af6fe3 100644
--- a/window.c
+++ b/window.c
@@ -1553,7 +1553,7 @@ int GetMenuItemIndex(const Window *w, int x, int y)
 	return -1;
 }
 
-void InvalidateWindow(byte cls, WindowNumber number)
+void InvalidateWindow(WindowClass cls, WindowNumber number)
 {
 	const Window* w;
 
@@ -1572,7 +1572,7 @@ void InvalidateWidget(const Window* w, byte widget_index)
 	SetDirtyBlocks(w->left + wi->left, w->top + wi->top, w->left + wi->right + 1, w->top + wi->bottom + 1);
 }
 
-void InvalidateWindowWidget(byte cls, WindowNumber number, byte widget_index)
+void InvalidateWindowWidget(WindowClass cls, WindowNumber number, byte widget_index)
 {
 	const Window* w;
 
@@ -1583,7 +1583,7 @@ void InvalidateWindowWidget(byte cls, WindowNumber number, byte widget_index)
 	}
 }
 
-void InvalidateWindowClasses(byte cls)
+void InvalidateWindowClasses(WindowClass cls)
 {
 	const Window* w;
 
diff --git a/window.h b/window.h
index f23906a14..1a0bf3e87 100644
--- a/window.h
+++ b/window.h
@@ -212,8 +212,8 @@ enum WindowKeyCodes {
 
 typedef struct WindowDesc {
 	int16 left, top, width, height;
-	byte cls;
-	byte parent_cls;
+	WindowClass cls;
+	WindowClass parent_cls;
 	uint32 flags;
 	const Widget *widgets;
 	WindowProc *proc;