--- a/functions.h	Sat Dec 24 13:22:38 2005 +0000
+++ b/functions.h	Sat Dec 24 15:01:17 2005 +0000
@@ -191,9 +191,9 @@
 /* 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);
 

--- a/gui.h	Sat Dec 24 13:22:38 2005 +0000
+++ b/gui.h	Sat Dec 24 15:01:17 2005 +0000
@@ -126,7 +126,7 @@
 
 /* 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);

--- a/network_gui.c	Sat Dec 24 13:22:38 2005 +0000
+++ b/network_gui.c	Sat Dec 24 15:01:17 2005 +0000
@@ -1397,7 +1397,7 @@
 	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;
 

--- a/window.c	Sat Dec 24 13:22:38 2005 +0000
+++ b/window.c	Sat Dec 24 15:01:17 2005 +0000
@@ -1553,7 +1553,7 @@
 	return -1;
 }
 
-void InvalidateWindow(byte cls, WindowNumber number)
+void InvalidateWindow(WindowClass cls, WindowNumber number)
 {
 	const Window* w;
 
@@ -1572,7 +1572,7 @@
 	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 InvalidateWindowClasses(byte cls)
+void InvalidateWindowClasses(WindowClass cls)
 {
 	const Window* w;
 

--- a/window.h	Sat Dec 24 13:22:38 2005 +0000
+++ b/window.h	Sat Dec 24 15:01:17 2005 +0000
@@ -212,8 +212,8 @@
 
 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;