(svn r6619) -Codechange: Use accessors for disabled_state.
authorbelugas
Tue, 03 Oct 2006 02:08:15 +0000
changeset 4709 eff35edfb653
parent 4708 5129e3add448
child 4710 a663b32b9f96
(svn r6619) -Codechange: Use accessors for disabled_state.
Another step toward merging XTDwidget.
The only two files not converted (window.h and widget.c) will be done at the very last commit)
aircraft_gui.c
airport_gui.c
depot_gui.c
genworld_gui.c
graph_gui.c
main_gui.c
music_gui.c
network_gui.c
news_gui.c
order_gui.c
player_gui.c
rail_gui.c
road_gui.c
roadveh_gui.c
settings_gui.c
ship_gui.c
smallmap_gui.c
station_gui.c
town_gui.c
train_gui.c
vehicle_gui.c
--- a/aircraft_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/aircraft_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -121,7 +121,7 @@
 		byte acc_planes;
 
 		if (tile == 0) {
-			SETBIT(w->disabled_state, 5);
+			DisableWindowWidget(w, 5);
 			acc_planes = ALL;
 		} else {
 			acc_planes = GetAirport(GetStationByTile(tile)->airport_type)->acc_planes;
@@ -269,9 +269,11 @@
 	case WE_PAINT: {
 		const Vehicle *v = GetVehicle(w->window_number);
 
-		w->disabled_state = v->owner == _local_player ? 0 : (1 << 2);
-		if (!_patches.servint_aircraft) // disable service-scroller when interval is set to disabled
-			w->disabled_state |= (1 << 5) | (1 << 6);
+		SetWindowWidgetDisabledState(w, 2, v->owner != _local_player);
+
+		/* Disable service-scroller when interval is set to disabled */
+		SetWindowWidgetDisabledState(w, 5, !_patches.servint_aircraft);
+		SetWindowWidgetDisabledState(w, 6, !_patches.servint_aircraft);
 
 		SetDParam(0, v->string_id);
 		SetDParam(1, v->unitnumber);
@@ -451,13 +453,11 @@
 	switch (e->event) {
 	case WE_PAINT: {
 		const Vehicle *v = GetVehicle(w->window_number);
-		uint32 disabled = 1 << 8;
 		StringID str;
 
-		if (IsAircraftInHangarStopped(v)) disabled = 0;
+		SetWindowWidgetDisabledState(w, 7, v->owner != _local_player);
+		SetWindowWidgetDisabledState(w, 8, !IsAircraftInHangarStopped(v) || v->owner != _local_player);
 
-		if (v->owner != _local_player) disabled |= 1 << 8 | 1 << 7;
-		w->disabled_state = disabled;
 
 		/* draw widgets & caption */
 		SetDParam(0, v->string_id);
--- a/airport_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/airport_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -143,6 +143,7 @@
 {
 	switch (e->event) {
 	case WE_PAINT: {
+		int i; // airport enabling loop
 		int sel;
 		int rad = 4; // default catchment radious
 		uint32 avail_airports;
@@ -156,10 +157,13 @@
 		if (!HASBIT(avail_airports, 0) && sel == AT_SMALL) sel = AT_LARGE;
 		if (!HASBIT(avail_airports, 1) && sel == AT_LARGE) sel = AT_SMALL;
 
-		/* 'Country Airport' starts at widget 3, and if its bit is set, it is
-		 * available, so take its opposite value to set the disabled_state. There
-		 * are 9 buildable airports, so XOR with 0x01FF (1 1111 1111) */
-		w->disabled_state = (avail_airports ^ 0x01FF) << 7;
+		/* 'Country Airport' starts at widget 7, and if its bit is set, it is
+		 * available, so take its opposite value to set the disabled state.
+		 * There are 9 buildable airports
+		 * XXX TODO : all airports should be held in arrays, with all relevant data.
+		 * This should be part of newgrf-airports, i suppose
+		 */
+		for (i = 0; i < 9; i++) SetWindowWidgetDisabledState(w, i + 7, !HASBIT(avail_airports, i));
 
 		_selected_airport_type = sel;
 		// select default the coverage area to 'Off' (16)
--- a/depot_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/depot_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -258,17 +258,20 @@
 static void DrawDepotWindow(Window *w)
 {
 	Vehicle **vl = WP(w, depot_d).vehicle_list;
-	TileIndex tile;
+	TileIndex tile = w->window_number;
 	int x, y, i, hnum, max;
 	uint16 num = WP(w, depot_d).engine_count;
-
-	tile = w->window_number;
+	bool is_localplayer = IsTileOwner(tile, _local_player);
 
 	/* setup disabled buttons */
-	w->disabled_state =
-		IsTileOwner(tile, _local_player) ? 0 : ( (1 << DEPOT_WIDGET_STOP_ALL) | (1 << DEPOT_WIDGET_START_ALL) |
-			(1 << DEPOT_WIDGET_SELL) | (1 << DEPOT_WIDGET_SELL_CHAIN) | (1 << DEPOT_WIDGET_SELL_ALL) |
-			(1 << DEPOT_WIDGET_BUILD) | (1 << DEPOT_WIDGET_CLONE) | (1 << DEPOT_WIDGET_AUTOREPLACE));
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_STOP_ALL,    !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_START_ALL,   !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_SELL,        !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_SELL_CHAIN,  !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_SELL_ALL,    !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_BUILD,       !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_CLONE,       !is_localplayer);
+	SetWindowWidgetDisabledState(w, DEPOT_WIDGET_AUTOREPLACE, !is_localplayer);
 
 	/* determine amount of items for scroller */
 	if (WP(w, depot_d).type == VEH_Train) {
@@ -740,14 +743,14 @@
 				} break;
 
 				case DEPOT_WIDGET_SELL: case DEPOT_WIDGET_SELL_CHAIN:
-					if (!HASBIT(w->disabled_state, DEPOT_WIDGET_SELL) &&
+					if (!IsWindowWidgetDisabled(w, DEPOT_WIDGET_SELL) &&
 						WP(w, depot_d).sel != INVALID_VEHICLE) {
 						Vehicle *v;
 						uint command;
 						int sell_cmd;
 						bool is_engine;
 
-						if (HASBIT(w->disabled_state, e->we.click.widget)) return;
+						if (IsWindowWidgetDisabled(w, e->we.click.widget)) return;
 						if (WP(w, depot_d).sel == INVALID_VEHICLE) return;
 
 						HandleButtonClick(w, e->we.click.widget);
--- a/genworld_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/genworld_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -209,7 +209,6 @@
 
 	switch (e->event) {
 	case WE_PAINT:
-		w->disabled_state = 0;
 		/* TODO -- Above and below you see some lines commented out with '//' in
 		 *  front of it. This is because currently the widget system can't handle
 		 *  more than 32 widgets per window, and we need 34. Therefor we draw
@@ -223,18 +222,23 @@
 
 		/* You can't select smoothness if not terragenesis */
 //		if (_patches_newgame.land_generator == 0) w->disabled_state |= (1 << 32 | 1 << 33);
-		if (_patches_newgame.land_generator == 0) w->disabled_state |= (1 << 30 | 1 << 31);
+		SetWindowWidgetDisabledState(w, 30, _patches_newgame.land_generator == 0);
+		SetWindowWidgetDisabledState(w, 31, _patches_newgame.land_generator == 0);
 		/* Disable snowline if not hilly */
-		if (_opt_newgame.landscape != LT_HILLY)   w->disabled_state |= (1 << 21 | 1 << 22 | 1 << 23);
+		SetWindowWidgetDisabledState(w, 22, _opt_newgame.landscape != LT_HILLY);
 		/* Disable town and industry in SE */
-		if (_game_mode == GM_EDITOR)              w->disabled_state |= (1 << 11 | 1 << 12 | 1 << 13 | 1 << 14 | 1 << 24 | 1 << 25);
+		SetWindowWidgetDisabledState(w, 11, _game_mode == GM_EDITOR);
+		SetWindowWidgetDisabledState(w, 12, _game_mode == GM_EDITOR);
+		SetWindowWidgetDisabledState(w, 13, _game_mode == GM_EDITOR);
+		SetWindowWidgetDisabledState(w, 14, _game_mode == GM_EDITOR);
+		SetWindowWidgetDisabledState(w, 24, _game_mode == GM_EDITOR);
+		SetWindowWidgetDisabledState(w, 25, _game_mode == GM_EDITOR);
 
-		if (_patches_newgame.starting_year <= MIN_YEAR) SETBIT(w->disabled_state, 18);
-		if (_patches_newgame.starting_year >= MAX_YEAR) SETBIT(w->disabled_state, 20);
-		if (_patches_newgame.snow_line_height <= 2 )    SETBIT(w->disabled_state, 21);
-		if (_patches_newgame.snow_line_height >= 13)    SETBIT(w->disabled_state, 23);
+		SetWindowWidgetDisabledState(w, 18, _patches_newgame.starting_year <= MIN_YEAR);
+		SetWindowWidgetDisabledState(w, 20, _patches_newgame.starting_year >= MAX_YEAR);
+		SetWindowWidgetDisabledState(w, 21, _patches_newgame.snow_line_height <= 2 || _opt_newgame.landscape != LT_HILLY);
+		SetWindowWidgetDisabledState(w, 23, _patches_newgame.snow_line_height >= 13 || _opt_newgame.landscape != LT_HILLY);
 
-		w->click_state = (w->click_state & ~(0xF << 3)) | (1 << (_opt_newgame.landscape + 3));
 		DrawWindowWidgets(w);
 
 		y = (mode == GLWP_HEIGHTMAP) ? 22 : 0;
@@ -576,11 +580,10 @@
 
 	switch (e->event) {
 	case WE_PAINT:
-		w->disabled_state = 0;
-		if (_patches_newgame.starting_year <= MIN_YEAR)  SETBIT(w->disabled_state, 14);
-		if (_patches_newgame.starting_year >= MAX_YEAR)  SETBIT(w->disabled_state, 16);
-		if (_patches_newgame.se_flat_world_height <= 0)  SETBIT(w->disabled_state, 17);
-		if (_patches_newgame.se_flat_world_height >= 15) SETBIT(w->disabled_state, 19);
+		SetWindowWidgetDisabledState(w, 14, _patches_newgame.starting_year <= MIN_YEAR);
+		SetWindowWidgetDisabledState(w, 16, _patches_newgame.starting_year >= MAX_YEAR);
+		SetWindowWidgetDisabledState(w, 17, _patches_newgame.se_flat_world_height <= 0);
+		SetWindowWidgetDisabledState(w, 19, _patches_newgame.se_flat_world_height >= 15);
 
 		w->click_state = (w->click_state & ~(0xF << 3)) | (1 << (_opt_newgame.landscape + 3));
 		DrawWindowWidgets(w);
--- a/graph_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/graph_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -899,9 +899,9 @@
 			for (i = 0; i < MAX_PLAYERS; i++) {
 				if (!GetPlayer(i)->is_active) {
 					// Check if we have the player as an active player
-					if (!(w->disabled_state & (1 << (i + 13)))) {
+					if (!IsWindowWidgetDisabled(w, i + 13)) {
 						// Bah, player gone :(
-						w->disabled_state += 1 << (i + 13);
+						DisableWindowWidget(w, i + 13);
 						// Is this player selected? If so, select first player (always save? :s)
 						if (w->click_state == 1U << (i + 13)) w->click_state = 1 << 13;
 						// We need a repaint
@@ -911,9 +911,9 @@
 				}
 
 				// Check if we have the player marked as inactive
-				if (w->disabled_state & (1 << (i + 13))) {
+				if (IsWindowWidgetDisabled(w, i + 13)) {
 					// New player! Yippie :p
-					w->disabled_state -= 1 << (i + 13);
+					EnableWindowWidget(w, i + 13);
 					// We need a repaint
 					SetWindowDirty(w);
 				}
@@ -1000,7 +1000,7 @@
 			// Check which button is clicked
 			if (IS_INT_INSIDE(e->we.click.widget, 13, 21)) {
 				// Is it no on disable?
-				if ((w->disabled_state & (1 << e->we.click.widget)) == 0) {
+				if (!IsWindowWidgetDisabled(w, e->we.click.widget)) {
 					w->click_state = 1 << e->we.click.widget;
 					SetWindowDirty(w);
 				}
@@ -1011,11 +1011,9 @@
 			int i;
 			Player *p2;
 
-			w->disabled_state = 0;
-
-			// Hide the player who are not active
+			/* Disable the players who are not active */
 			for (i = 0; i < MAX_PLAYERS; i++) {
-				if (!GetPlayer(i)->is_active) w->disabled_state += 1 << (i + 13);
+				SetWindowWidgetDisabledState(w, i + 13, !GetPlayer(i)->is_active);
 			}
 			// Update all player stats with the current data
 			//  (this is because _score_info is not saved to a savegame)
--- a/main_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/main_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -107,7 +107,7 @@
 {
 	uint32 mask = 1 << widget;
 
-	if (w->disabled_state & mask) return false;
+	if (IsWindowWidgetDisabled(w, widget)) return false;
 
 	SndPlayFx(SND_15_BEEP);
 	SetWindowDirty(w);
@@ -869,12 +869,9 @@
 		assert(wt);
 
 		// update the toolbar button too
-		CLRBIT(wt->disabled_state, button);
-		CLRBIT(wt->disabled_state, button + 1);
-		switch (vp->zoom) {
-			case 0: SETBIT(wt->disabled_state, button); break;
-			case 2: SETBIT(wt->disabled_state, button + 1); break;
-		}
+		SetWindowWidgetDisabledState(wt, button, vp->zoom == 0);
+		SetWindowWidgetDisabledState(wt, button + 1, vp->zoom == 2);
+
 		SetWindowDirty(wt);
 	}
 
@@ -1754,24 +1751,27 @@
 {
 	switch (e->event) {
 	case WE_PAINT: {
+		bool is_spectator = _current_player == OWNER_SPECTATOR;
 
 		// Draw brown-red toolbar bg.
 		GfxFillRect(0, 0, w->width-1, w->height-1, 0xB2);
 		GfxFillRect(0, 0, w->width-1, w->height-1, 0xB4 | PALETTE_MODIFIER_GREYOUT);
 
-		// if spectator, disable things
-		if (_current_player == OWNER_SPECTATOR){
-			w->disabled_state |= (1 << 19) | (1<<20) | (1<<21) | (1<<22) | (1<<23);
-		} else {
-			w->disabled_state &= ~((1 << 19) | (1<<20) | (1<<21) | (1<<22) | (1<<23));
-		}
+		/* If spectator, disable all construction buttons
+		 * ie : Build road, rail, ships, airports and landscaping
+		 * Since enabled state is the default, just disable when needed */
+		SetWindowWidgetDisabledState(w, 19, is_spectator);
+		SetWindowWidgetDisabledState(w, 20, is_spectator);
+		SetWindowWidgetDisabledState(w, 21, is_spectator);
+		SetWindowWidgetDisabledState(w, 22, is_spectator);
+		SetWindowWidgetDisabledState(w, 23, is_spectator);
 
 		DrawWindowWidgets(w);
 		break;
 	}
 
 	case WE_CLICK: {
-		if (_game_mode != GM_MENU && !HASBIT(w->disabled_state, e->we.click.widget))
+		if (_game_mode != GM_MENU && !IsWindowWidgetDisabled(w, e->we.click.widget))
 			_toolbar_button_procs[e->we.click.widget](w);
 	} break;
 
@@ -1961,16 +1961,8 @@
 {
 	switch (e->event) {
 	case WE_PAINT:
-		if (_patches_newgame.starting_year <= MIN_YEAR) {
-			SETBIT(w->disabled_state, 6);
-		} else {
-			CLRBIT(w->disabled_state, 6);
-		}
-		if (_patches_newgame.starting_year >= MAX_YEAR) {
-			SETBIT(w->disabled_state, 7);
-		} else {
-			CLRBIT(w->disabled_state, 7);
-		}
+		SetWindowWidgetDisabledState(w, 6, _patches_newgame.starting_year <= MIN_YEAR);
+		SetWindowWidgetDisabledState(w, 7, _patches_newgame.starting_year >= MAX_YEAR);
 
 		// Draw brown-red toolbar bg.
 		GfxFillRect(0, 0, w->width-1, w->height-1, 0xB2);
@@ -2368,19 +2360,15 @@
 
 	if (_game_mode != GM_EDITOR) {
 		w = AllocateWindowDesc(&_toolb_normal_desc);
-		w->disabled_state = 1 << 18;
+		DisableWindowWidget(w, 18);
 	} else {
 		w = AllocateWindowDesc(&_toolb_scen_desc);
-		w->disabled_state = 1 << 10;
+		DisableWindowWidget(w, 10);
 	}
 	CLRBITS(w->flags4, WF_WHITE_BORDER_MASK);
 
-	if (_networking) {
-		/* If networking, disable fast-forward button */
-		SETBIT(w->disabled_state, 1);
-		/* If not server, disable pause button */
-		if (!_network_server) SETBIT(w->disabled_state, 0);
-	}
+	SetWindowWidgetDisabledState(w, 0, _networking && !_network_server); // if not server, disable pause button
+	SetWindowWidgetDisabledState(w, 1, _networking); // if networking, disable fast-forward button
 
 	/* 'w' is for sure a WC_MAIN_TOOLBAR */
 	PositionMainToolbar(w);
--- a/music_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/music_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -199,7 +199,7 @@
 		uint i;
 		int y;
 
-		w->disabled_state = (msf.playlist  <= 3) ? (1 << 11) : 0;
+		SetWindowWidgetDisabledState(w, 11, msf.playlist <= 3);
 		w->click_state |= 0x18;
 		DrawWindowWidgets(w);
 
--- a/network_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/network_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -238,18 +238,12 @@
 		}
 		if (ld->flags & VL_RESORT) SortNetworkGameList(&WP(w, network_ql_d));
 
-		w->disabled_state = 0;
-
-		if (sel == NULL) {
-			SETBIT(w->disabled_state, 16); SETBIT(w->disabled_state, 17);
-		} else if (!sel->online) {
-			SETBIT(w->disabled_state, 16); // Server offline, join button disabled
-		} else if (sel->info.clients_on >= sel->info.clients_max) {
-			SETBIT(w->disabled_state, 16); // Server full, join button disabled
-		} else if (!sel->info.compatible) {
-			// revisions don't match, check if server has no revision; then allow connection
-			SETBIT(w->disabled_state, 16); // Revision mismatch, join button disabled
-		}
+		SetWindowWidgetDisabledState(w, 17, sel == NULL);
+		/* Join Button disabling conditions */
+		SetWindowWidgetDisabledState(w, 16, sel == NULL || // no Selected Server
+				!sel->online || // Server offline
+				sel->info.clients_on >= sel->info.clients_max || // Server full
+				!sel->info.compatible); // Revision mismatch
 
 		SetDParam(0, 0x00);
 		SetDParam(7, _lan_internet_types_dropdown[_network_lan_internet]);
@@ -823,14 +817,12 @@
 		const NetworkGameInfo *gi = &nd->server->info;
 		int y = NET_PRC__OFFSET_TOP_WIDGET_COMPANY, pos;
 
-		w->disabled_state = 0;
-
-		if (nd->company == (byte)-1) SETBIT(w->disabled_state, 7);
-		if (gi->companies_on >= gi->companies_max) SETBIT(w->disabled_state, 8);
-		if (gi->spectators_on >= gi->spectators_max) SETBIT(w->disabled_state, 9);
+		SetWindowWidgetDisabledState(w, 7, nd->company == (byte)-1);
+		SetWindowWidgetDisabledState(w, 8, gi->companies_on >= gi->companies_max);
 		/* You can not join a server as spectator when it has no companies active..
 		 * it causes some nasty crashes */
-		if (gi->companies_on == 0) SETBIT(w->disabled_state, 9);
+		SetWindowWidgetDisabledState(w, 9, gi->spectators_on >= gi->spectators_max ||
+				gi->companies_on == 0);
 
 		DrawWindowWidgets(w);
 
--- a/news_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/news_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -685,32 +685,14 @@
 static void SetMessageButtonStates(Window *w, byte value, int element)
 {
 	element *= 2;
-	switch (value) {
-	case 0: /* Off */
-		SETBIT(w->disabled_state, element + 3);
-		CLRBIT(w->disabled_state, element + 3 + 1);
-		break;
-	case 1: /* Summary */
-		CLRBIT(w->disabled_state, element + 3);
-		CLRBIT(w->disabled_state, element + 3 + 1);
-		break;
-	case 2: /* Full */
-		SETBIT(w->disabled_state, element + 3 + 1);
-		CLRBIT(w->disabled_state, element + 3);
-		break;
-	default: NOT_REACHED();
-	}
+
+	SetWindowWidgetDisabledState(w, element + 3, value == 0);
+	SetWindowWidgetDisabledState(w, element + 3 + 1, value == 2);
 }
 
 static void MessageOptionsWndProc(Window *w, WindowEvent *e)
 {
 	static const StringID message_opt[] = {STR_OFF, STR_SUMMARY, STR_FULL, INVALID_STRING_ID};
-	static const uint32 message_val[] = {0x0, 0x55555555, 0xAAAAAAAA}; // 0x555.. = 01010101010101010101 (all summary), 286.. 1010... (full)
-	static const uint32 message_dis[] = {
-		(1 << 3) | (1 << 5) | (1 << 7) | (1 << 9)  | (1 << 11) | (1 << 13) | (1 << 15) | (1 << 17) | (1 << 19) | (1 << 21),
-		0,
-		(1 << 4) | (1 << 6) | (1 << 8) | (1 << 10) | (1 << 12) | (1 << 14) | (1 << 16) | (1 << 18) | (1 << 20) | (1 << 22),
-	};
 
 	/* WP(w, def_d).data_1 are stores the clicked state of the fake widgets
 	 * WP(w, def_d).data_2 stores state of the ALL on/off/summary button */
@@ -784,18 +766,23 @@
 		} break;
 		} break;
 
-	case WE_DROPDOWN_SELECT: /* Select all settings for newsmessages */
+	case WE_DROPDOWN_SELECT: {/* Select all settings for newsmessages */
+		int i;
+
 		WP(w, def_d).data_2 = e->we.dropdown.index;
-		_news_display_opt = message_val[WP(w, def_d).data_2];
-		w->disabled_state = message_dis[WP(w, def_d).data_2];
+
+		for (i = 0; i != 10; i++) {
+			SB(_news_display_opt, i*2, 2, e->we.dropdown.index);
+			SetMessageButtonStates(w, e->we.dropdown.index, i);
+		}
 		SetWindowDirty(w);
 		break;
+		}
 
 	case WE_TIMEOUT: /* XXX - Hack to animate 'fake' buttons */
 		WP(w, def_d).data_1 = 0;
 		SetWindowDirty(w);
 		break;
-
 	}
 }
 
--- a/order_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/order_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -57,22 +57,13 @@
 	int sel;
 	int y, i;
 	bool shared_orders;
+	bool not_localplayer;
 	byte color;
 
 	v = GetVehicle(w->window_number);
-
-	w->disabled_state = (v->owner == _local_player) ? 0 : (
-		1 << 4 |   //skip
-		1 << 5 |   //delete
-		1 << 6 |   //non-stop
-		1 << 7 |   //go-to
-		1 << 8 |   //full load
-		1 << 9 |   //unload
-		1 << 10    //transfer
-		);
+	not_localplayer = v->owner != _local_player;
 
 	if (v->type != VEH_Train) {
-		SETBIT(w->disabled_state, 6); // Disable non-stop for non-trains
 		switch (v->type) {
 			case VEH_Road:     w->widget[11].data = STR_LORRY; break;
 			case VEH_Ship:     w->widget[11].data = STR_SHIP;  break;
@@ -83,16 +74,6 @@
 
 	shared_orders = IsOrderListShared(v);
 
-	if (!shared_orders || v->orders == NULL) {
-		SETBIT(w->disabled_state, 11); // Disable list of vehicles with the same shared orders if there are no list
-	}
-
-	if ((uint)v->num_orders + (shared_orders?1:0) <= (uint)WP(w,order_d).sel)
-		SETBIT(w->disabled_state, 5); /* delete */
-
-	if (v->num_orders == 0)
-		SETBIT(w->disabled_state, 4); /* skip */
-
 	SetVScrollCount(w, v->num_orders + 1);
 
 	sel = OrderGetSel(w);
@@ -100,33 +81,44 @@
 
 	order = GetVehicleOrder(v, sel);
 
+	/* skip */
+	SetWindowWidgetDisabledState(w,  4, not_localplayer || v->num_orders == 0);
+
+	/* delete */
+	SetWindowWidgetDisabledState(w,  5, not_localplayer ||
+			(uint)v->num_orders + (shared_orders ? 1 : 0) <= (uint)WP(w, order_d).sel);
+
+	/* non-stop only for trains */
+	SetWindowWidgetDisabledState(w,  6, not_localplayer || v->type != VEH_Train
+			|| order == NULL);
+	SetWindowWidgetDisabledState(w,  7, not_localplayer); // go-to
+	SetWindowWidgetDisabledState(w,  8, not_localplayer || order == NULL); // full load
+	SetWindowWidgetDisabledState(w,  9, not_localplayer || order == NULL); // unload
+	SetWindowWidgetDisabledState(w, 10, not_localplayer || order == NULL); // transfer
+	SetWindowWidgetDisabledState(w, 11, !shared_orders || v->orders == NULL); // Disable list of vehicles with the same shared orders if there are no list
+
 	if (order != NULL) {
 		switch (order->type) {
 			case OT_GOTO_STATION:
 				break;
 
 			case OT_GOTO_DEPOT:
-				SETBIT(w->disabled_state, 9);  /* unload */
-				SETBIT(w->disabled_state, 10); /* transfer */
+				DisableWindowWidget(w,  9);
+				DisableWindowWidget(w, 10);
 				SetDParam(2,STR_SERVICE);
 				break;
 
 			case OT_GOTO_WAYPOINT:
-				SETBIT(w->disabled_state, 8);  /* full load */
-				SETBIT(w->disabled_state, 9);  /* unload */
-				SETBIT(w->disabled_state, 10); /* transfer */
+				DisableWindowWidget(w,  8);
+				DisableWindowWidget(w,  9);
+				DisableWindowWidget(w, 10);
 				break;
 
-			default:
-				SETBIT(w->disabled_state, 6);  /* nonstop */
-				SETBIT(w->disabled_state, 8);  /* full load */
-				SETBIT(w->disabled_state, 9);  /* unload */
+			default: // every other orders
+				DisableWindowWidget(w, 6);
+				DisableWindowWidget(w, 8);
+				DisableWindowWidget(w, 9);
 		}
-	} else {
-		SETBIT(w->disabled_state, 6);          /* nonstop */
-		SETBIT(w->disabled_state, 8);          /* full load */
-		SETBIT(w->disabled_state, 9);          /* unload */
-		SETBIT(w->disabled_state, 10);         /* transfer */
 	}
 
 	SetDParam(0, v->string_id);
@@ -477,7 +469,7 @@
 			if (e->we.keypress.keycode == _order_keycodes[i]) {
 				e->we.keypress.cont = false;
 				//see if the button is disabled
-				if (!HASBIT(w->disabled_state, i + 4)) _order_button_proc[i](w, v);
+				if (!IsWindowWidgetDisabled(w, i + 4)) _order_button_proc[i](w, v);
 				break;
 			}
 		}
--- a/player_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/player_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -154,7 +154,7 @@
 		PlayerID player = w->window_number;
 		const Player *p = GetPlayer(player);
 
-		w->disabled_state = p->current_loan != 0 ? 0 : (1 << 7);
+		SetWindowWidgetDisabledState(w, 7, p->current_loan == 0);
 
 		SetDParam(0, p->name_1);
 		SetDParam(1, p->name_2);
@@ -322,11 +322,13 @@
 			LiveryScheme scheme = LS_DEFAULT;
 			int y = 51;
 
-			if ((WP(w, livery_d).sel == 0)) {
-				/* Disable dropdown controls if no scheme is selected */
-				w->disabled_state = 1 << 9 | 1 << 10 | 1 << 11 | 1 << 12;
-			} else {
-				w->disabled_state = 0;
+			/* Disable dropdown controls if no scheme is selected */
+			SetWindowWidgetDisabledState(w,  9, (WP(w, livery_d).sel == 0));
+			SetWindowWidgetDisabledState(w, 10, (WP(w, livery_d).sel == 0));
+			SetWindowWidgetDisabledState(w, 11, (WP(w, livery_d).sel == 0));
+			SetWindowWidgetDisabledState(w, 12, (WP(w, livery_d).sel == 0));
+
+			if (!(WP(w, livery_d).sel == 0)) {
 				for (scheme = 0; scheme < LS_END; scheme++) {
 					if (HASBIT(WP(w, livery_d).sel, scheme)) break;
 				}
@@ -649,29 +651,29 @@
 	switch (e->event) {
 	case WE_PAINT: {
 		const Player *p = GetPlayer(w->window_number);
-		uint32 dis = 0;
 
 		if (!IsWindowOfPrototype(w, _other_player_company_widgets)) {
 			AssignWidgetToWindow(w, (p->location_of_house != 0) ? _my_player_company_bh_widgets : _my_player_company_widgets);
 
 			SetWindowWidgetHiddenState(w, 11, !_networking); // Hide company-password widget
 		} else {
-			if (p->location_of_house == 0) SETBIT(dis, 7);
+			SetWindowWidgetDisabledState(w, 7, p->location_of_house == 0);
 
-			if (_patches.allow_shares) { /* shares are allowed */
+			if (_patches.allow_shares) { // Shares are allowed
 				/* If all shares are owned by someone (none by nobody), disable buy button */
-				if (GetAmountOwnedBy(p, OWNER_SPECTATOR) == 0) SETBIT(dis, 9);
-
-				/* Only 25% left to buy. If the player is human, disable buying it up.. TODO issues! */
-				if (GetAmountOwnedBy(p, OWNER_SPECTATOR) == 1 && !p->is_ai) SETBIT(dis, 9);
+				SetWindowWidgetDisabledState(w, 9, GetAmountOwnedBy(p, OWNER_SPECTATOR) == 0 ||
+						/* Only 25% left to buy. If the player is human, disable buying it up.. TODO issues! */
+						(GetAmountOwnedBy(p, OWNER_SPECTATOR) == 1 && !p->is_ai) ||
+						/* Spectators cannot do anything of course */
+						_local_player == OWNER_SPECTATOR);
 
 				/* If the player doesn't own any shares, disable sell button */
-				if (GetAmountOwnedBy(p, _local_player) == 0) SETBIT(dis, 10);
-
-				/* Spectators cannot do anything of course */
-				if (_local_player == OWNER_SPECTATOR) dis |= (1 << 9) | (1 << 10);
-			} else { /* shares are not allowed, disable buy/sell buttons */
-				dis |= (1 << 9) | (1 << 10);
+				SetWindowWidgetDisabledState(w, 10, (GetAmountOwnedBy(p, _local_player) == 0) ||
+						/* Spectators cannot do anything of course */
+						_local_player == OWNER_SPECTATOR);
+			} else { // Shares are not allowed, disable buy/sell buttons
+				DisableWindowWidget(w,  9);
+				DisableWindowWidget(w, 10);
 			}
 		}
 
@@ -679,7 +681,6 @@
 		SetDParam(1, p->name_2);
 		SetDParam(2, GetPlayerNameString((byte)w->window_number, 3));
 
-		w->disabled_state = dis;
 		DrawWindowWidgets(w);
 
 		SetDParam(0, p->inaugurated_year);
--- a/rail_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/rail_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -292,7 +292,7 @@
 
 static void BuildRailClick_Remove(Window *w)
 {
-	if (HASBIT(w->disabled_state, 16)) return;
+	if (IsWindowWidgetDisabled(w, 16)) return;
 	SetWindowDirty(w);
 	SndPlayFx(SND_15_BEEP);
 
@@ -405,24 +405,25 @@
 };
 
 
+static void UpdateRemoveWidgetStatus(Window *w, int clicked_widget)
+{
+	switch (clicked_widget) {
+		case 4: case 5: case 6: case 7: case 8: case 11: case 12: case 13: EnableWindowWidget(w, 16); break;
+		default: DisableWindowWidget(w, 16); w->click_state &= ~(1 << 16); break;
+	}
+}
+
 static void BuildRailToolbWndProc(Window *w, WindowEvent *e)
 {
 	switch (e->event) {
-	case WE_PAINT:
-		w->disabled_state &= ~(1 << 16);
-		if (!(w->click_state & ((1<<4)|(1<<5)|(1<<6)|(1<<7)|(1<<8)|(1<<11)|(1<<12)|(1<<13)))) {
-			w->disabled_state |= (1 << 16);
-			w->click_state &= ~(1<<16);
-		}
-		DrawWindowWidgets(w);
-		break;
-
+	case WE_PAINT: DrawWindowWidgets(w); break;
 	case WE_CLICK:
 		if (e->we.click.widget >= 4) {
 			_remove_button_clicked = false;
 			_build_railroad_button_proc[e->we.click.widget - 4](w);
 		}
-	break;
+		UpdateRemoveWidgetStatus(w, e->we.click.widget);
+		break;
 
 	case WE_KEYPRESS: {
 		uint i;
@@ -432,6 +433,7 @@
 				e->we.keypress.cont = false;
 				_remove_button_clicked = false;
 				_build_railroad_button_proc[i](w);
+				UpdateRemoveWidgetStatus(w, i);
 				break;
 			}
 		}
@@ -651,10 +653,9 @@
 			SetTileSelectBigSize(-rad, -rad, 2 * rad, 2 * rad);
 
 		/* Update buttons for correct spread value */
-		w->disabled_state = 0;
 		for (bits = _patches.station_spread; bits < 7; bits++) {
-			SETBIT(w->disabled_state, bits + 5);
-			SETBIT(w->disabled_state, bits + 12);
+			DisableWindowWidget(w, bits + 5);
+			DisableWindowWidget(w, bits + 12);
 		}
 
 		if (newstations) {
@@ -662,8 +663,8 @@
 
 			if (statspec != NULL) {
 				for (bits = 0; bits < 7; bits++) {
-					if (HASBIT(statspec->disallowed_platforms, bits)) SETBIT(w->disabled_state, bits +  5);
-					if (HASBIT(statspec->disallowed_lengths,   bits)) SETBIT(w->disabled_state, bits + 12);
+					SetWindowWidgetDisabledState(w, bits +  5, HASBIT(statspec->disallowed_platforms, bits));
+					SetWindowWidgetDisabledState(w, bits + 12, HASBIT(statspec->disallowed_lengths,   bits));
 				}
 			}
 		}
--- a/road_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/road_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -155,7 +155,7 @@
 
 static void BuildRoadClick_Remove(Window *w)
 {
-	if (HASBIT(w->disabled_state, 11)) return;
+	if (IsWindowWidgetDisabled(w, 11)) return;
 	SetWindowDirty(w);
 	SndPlayFx(SND_15_BEEP);
 	TOGGLEBIT(w->click_state, 11);
@@ -184,10 +184,11 @@
 {
 	switch (e->event) {
 	case WE_PAINT:
-		w->disabled_state &= ~(1 << 11);
 		if (!(w->click_state & ((1<<3)|(1<<4)))) {
-			w->disabled_state |= (1 << 11);
+			DisableWindowWidget(w, 11);
 			w->click_state &= ~(1<<11);
+		} else {
+			EnableWindowWidget(w, 11);
 		}
 		DrawWindowWidgets(w);
 		break;
--- a/roadveh_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/roadveh_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -86,9 +86,10 @@
 		const Vehicle *v = GetVehicle(w->window_number);
 		StringID str;
 
-		w->disabled_state = v->owner == _local_player ? 0 : (1 << 2);
+		SetWindowWidgetDisabledState(w, 2, v->owner != _local_player);
 		// disable service-scroller when interval is set to disabled
-		if (!_patches.servint_roadveh) w->disabled_state |= (1 << 5) | (1 << 6);
+		SetWindowWidgetDisabledState(w, 5, !_patches.servint_roadveh);
+		SetWindowWidgetDisabledState(w, 6, !_patches.servint_roadveh);
 
 		SetDParam(0, v->string_id);
 		SetDParam(1, v->unitnumber);
@@ -236,10 +237,11 @@
 		Vehicle *v = GetVehicle(w->window_number);
 		StringID str;
 
-		w->disabled_state = (v->owner != _local_player) ? (1 << 8 | 1 << 7 | 1 << 12) : 0;
-
+		SetWindowWidgetDisabledState(w, 7, v->owner != _local_player);
+		SetWindowWidgetDisabledState(w, 8, v->owner != _local_player);
 		/* Disable refit button if vehicle not refittable */
-		if (_engine_info[v->engine_type].refit_mask == 0) SETBIT(w->disabled_state, 12);
+		SetWindowWidgetDisabledState(w, 12, v->owner != _local_player ||
+				_engine_info[v->engine_type].refit_mask == 0);
 
 		/* draw widgets & caption */
 		SetDParam(0, v->string_id);
@@ -403,7 +405,7 @@
 	int sel;
 	int y;
 
-	if (w->window_number == 0) w->disabled_state = 1 << 5;
+	SetWindowWidgetDisabledState(w, 5, w->window_number == 0);
 
 	count = 0;
 	for (e = ROAD_ENGINES_INDEX; e < ROAD_ENGINES_INDEX + NUM_ROAD_ENGINES; e++) {
@@ -541,3 +543,4 @@
 	}
 }
 
+
--- a/settings_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/settings_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -95,7 +95,9 @@
 	case WE_PAINT: {
 		int i;
 		StringID str = STR_02BE_DEFAULT;
-		w->disabled_state = (_vehicle_design_names & 1) ? (++str, 0) : (1 << 21);
+
+		SetWindowWidgetDisabledState(w, 21, !(_vehicle_design_names & 1));
+		if (!IsWindowWidgetDisabled(w, 21)) str = STR_02BF_CUSTOM;
 		SetDParam(0, str);
 		SetDParam(1, _currency_specs[_opt_ptr->currency].name);
 		SetDParam(2, STR_UNITS_IMPERIAL + _opt_ptr->units);
@@ -381,17 +383,15 @@
 static void GameDifficultyWndProc(Window *w, WindowEvent *e)
 {
 	switch (e->event) {
-		case WE_CREATE: /* Setup disabled buttons when creating window */
-		// disable all other difficulty buttons during gameplay except for 'custom'
-		w->disabled_state = (_game_mode != GM_NORMAL) ? 0 : (1 << 3) | (1 << 4) | (1 << 5) | (1 << 6);
+	case WE_CREATE: // Setup disabled buttons when creating window
+		/* disable all other difficulty buttons during gameplay except for 'custom' */
+		SetWindowWidgetDisabledState(w,  3, _game_mode == GM_NORMAL);
+		SetWindowWidgetDisabledState(w,  4, _game_mode == GM_NORMAL);
+		SetWindowWidgetDisabledState(w,  5, _game_mode == GM_NORMAL);
+		SetWindowWidgetDisabledState(w,  6, _game_mode == GM_NORMAL);
+		SetWindowWidgetDisabledState(w,  7, _game_mode == GM_EDITOR || _networking); // highscore chart in multiplayer
+		SetWindowWidgetDisabledState(w, 10, _networking && !_network_server); // Save-button in multiplayer (and if client)
 
-		if (_game_mode == GM_EDITOR) SETBIT(w->disabled_state, 7);
-
-		if (_networking) {
-			SETBIT(w->disabled_state, 7); // disable highscore chart in multiplayer
-			if (!_network_server)
-				SETBIT(w->disabled_state, 10); // Disable save-button in multiplayer (and if client)
-		}
 		break;
 	case WE_PAINT: {
 		uint32 click_a, click_b, disabled;
@@ -1049,7 +1049,9 @@
 	w->vscroll.cap = 12;
 	w->vscroll.count = count;
 	w->vscroll.pos = 0;
-	w->disabled_state = (1 << 5) | (1 << 6) | (1 << 7);
+	DisableWindowWidget(w, 5);  // Small up arrow
+	DisableWindowWidget(w, 6);  // Small sown arrow
+	DisableWindowWidget(w, 7);  // Set parameter button
 }
 
 /**
--- a/ship_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/ship_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -85,9 +85,10 @@
 		const Vehicle *v = GetVehicle(w->window_number);
 		StringID str;
 
-		w->disabled_state = v->owner == _local_player ? 0 : (1 << 2);
+		SetWindowWidgetDisabledState(w, 2, v->owner != _local_player);
 		// disable service-scroller when interval is set to disabled
-		if (!_patches.servint_ships) w->disabled_state |= (1 << 5) | (1 << 6);
+		SetWindowWidgetDisabledState(w, 5, !_patches.servint_ships);
+		SetWindowWidgetDisabledState(w, 6, !_patches.servint_ships);
 
 		SetDParam(0, v->string_id);
 		SetDParam(1, v->unitnumber);
@@ -251,7 +252,7 @@
 			int sel;
 			int y;
 
-			if (w->window_number == 0) w->disabled_state = 1 << 5;
+			SetWindowWidgetDisabledState(w, 5, w->window_number == 0);
 
 			count = 0;
 			for (eid = SHIP_ENGINES_INDEX; eid < SHIP_ENGINES_INDEX + NUM_SHIP_ENGINES; eid++) {
@@ -374,16 +375,16 @@
 	switch (e->event) {
 		case WE_PAINT: {
 			Vehicle *v = GetVehicle(w->window_number);
-			uint32 disabled = 1<<8;
 			StringID str;
 
-			// Possible to refit?
+			/* Possible to refit? */
 			if (ShipVehInfo(v->engine_type)->refittable && IsShipInDepotStopped(v)) {
-				disabled = 0;
+				EnableWindowWidget(w, 7);
+				EnableWindowWidget(w, 8);
 			}
 
-			if (v->owner != _local_player) disabled |= 1<<8 | 1<<7;
-			w->disabled_state = disabled;
+			SetWindowWidgetDisabledState(w, 7, v->owner != _local_player);
+			SetWindowWidgetDisabledState(w, 8, v->owner != _local_player);
 
 			/* draw widgets & caption */
 			SetDParam(0, v->string_id);
--- a/smallmap_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/smallmap_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -1010,7 +1010,7 @@
 {
 	switch (e->event) {
 	case WE_CREATE: /* Disable zoom in button */
-		w->disabled_state = (1 << 5);
+		DisableWindowWidget(w, 5);
 		break;
 
 	case WE_PAINT:
--- a/station_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/station_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -541,13 +541,11 @@
 	}
 	SetVScrollCount(w, num);
 
-	w->disabled_state = st->owner == _local_player ? 0 : (1 << 9);
-
-	if (!(st->facilities & FACIL_TRAIN)) SETBIT(w->disabled_state,  10);
-	if (!(st->facilities & FACIL_TRUCK_STOP) &&
-			!(st->facilities & FACIL_BUS_STOP)) SETBIT(w->disabled_state, 11);
-	if (!(st->facilities & FACIL_AIRPORT)) SETBIT(w->disabled_state, 12);
-	if (!(st->facilities & FACIL_DOCK)) SETBIT(w->disabled_state, 13);
+	SetWindowWidgetDisabledState(w,  9, st->owner != _local_player);
+	SetWindowWidgetDisabledState(w, 10, !(st->facilities & FACIL_TRAIN));
+	SetWindowWidgetDisabledState(w, 11, !(st->facilities & FACIL_TRUCK_STOP) && !(st->facilities & FACIL_BUS_STOP));
+	SetWindowWidgetDisabledState(w, 12, !(st->facilities & FACIL_AIRPORT));
+	SetWindowWidgetDisabledState(w, 13, !(st->facilities & FACIL_DOCK));
 
 	SetDParam(0, st->index);
 	SetDParam(1, st->facilities);
--- a/town_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/town_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -106,7 +106,7 @@
 		if (WP(w,def_d).data_1 != -1 && !HASBIT(buttons, WP(w,def_d).data_1))
 			WP(w,def_d).data_1 = -1;
 
-		w->disabled_state = (WP(w,def_d).data_1 == -1) ? (1 << 6) : 0;
+		SetWindowWidgetDisabledState(w, 6, WP(w, def_d).data_1 == -1);
 
 		{
 			int y;
@@ -234,7 +234,7 @@
 	switch (e->event) {
 	case WE_PAINT:
 		// disable renaming town in network games if you are not the server
-		if (_networking && !_network_server) SETBIT(w->disabled_state, 8);
+		SetWindowWidgetDisabledState(w, 8, _networking && !_network_server);
 
 		SetDParam(0, t->index);
 		DrawWindowWidgets(w);
--- a/train_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/train_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -206,7 +206,7 @@
 	switch (e->event) {
 	case WE_PAINT:
 
-		if (w->window_number == 0) SETBIT(w->disabled_state, 5);
+		SetWindowWidgetDisabledState(w, 5, w->window_number == 0);
 
 		{
 			int count = 0;
@@ -424,21 +424,23 @@
 	case WE_PAINT: {
 		const Vehicle *v, *u;
 		StringID str;
+		bool is_localplayer;
 
 		v = GetVehicle(w->window_number);
 
-		if (v->owner != _local_player) {
-			w->disabled_state = 0x3380;
-		} else {
-			w->disabled_state = 0;
+		is_localplayer = v->owner == _local_player;
+		SetWindowWidgetDisabledState(w,  7, !is_localplayer);
+		SetWindowWidgetDisabledState(w,  8, !is_localplayer);
+		SetWindowWidgetDisabledState(w,  9, !is_localplayer);
+		SetWindowWidgetDisabledState(w, 12, !is_localplayer);
+		SetWindowWidgetDisabledState(w, 13, !is_localplayer);
 
-			SETBIT(w->disabled_state, 12);
-
+		if (is_localplayer) {
 			/* See if any vehicle can be refitted */
 			for (u = v; u != NULL; u = u->next) {
 				if (EngInfo(u->engine_type)->refit_mask != 0 ||
 						(!(RailVehInfo(v->engine_type)->flags & RVI_WAGON) && v->cargo_cap != 0)) {
-					CLRBIT(w->disabled_state, 12);
+					EnableWindowWidget(w, 12);
 					/* We have a refittable carriage, bail out */
 					break;
 				}
@@ -682,11 +684,12 @@
 
 	SetVScrollCount(w, num);
 
-	w->disabled_state = 1 << (det_tab + 9);
-	if (v->owner != _local_player) w->disabled_state |= (1 << 2);
+	DisableWindowWidget(w, det_tab + 9);
+	SetWindowWidgetDisabledState(w, 2, v->owner != _local_player);
 
-	// disable service-scroller when interval is set to disabled
-	if (!_patches.servint_trains) w->disabled_state |= (1 << 6) | (1 << 7);
+	/* disable service-scroller when interval is set to disabled */
+	SetWindowWidgetDisabledState(w, 6, !_patches.servint_trains);
+	SetWindowWidgetDisabledState(w, 7, !_patches.servint_trains);
 
 	SetDParam(0, v->string_id);
 	SetDParam(1, v->unitnumber);
@@ -801,11 +804,11 @@
 		case 10: // Information
 		case 11: // Capacities
 		case 12: // Total cargo
-			CLRBIT(w->disabled_state, 9);
-			CLRBIT(w->disabled_state, 10);
-			CLRBIT(w->disabled_state, 11);
-			CLRBIT(w->disabled_state, 12);
-			SETBIT(w->disabled_state, e->we.click.widget);
+			EnableWindowWidget(w,  9);
+			EnableWindowWidget(w, 10);
+			EnableWindowWidget(w, 11);
+			EnableWindowWidget(w, 12);
+			EnableWindowWidget(w, e->we.click.widget);
 			WP(w,traindetails_d).tab = e->we.click.widget - 9;
 			SetWindowDirty(w);
 			break;
--- a/vehicle_gui.c	Mon Oct 02 22:10:04 2006 +0000
+++ b/vehicle_gui.c	Tue Oct 03 02:08:15 2006 +0000
@@ -1020,25 +1020,19 @@
 				// or Both lists have the same vehicle selected
 				// or The selected replacement engine has a replacement (to prevent loops)
 				// or The right list (new replacement) has the existing replacement vehicle selected
-				if (selected_id[0] == INVALID_ENGINE ||
+				SetWindowWidgetDisabledState(w, 4,
+						selected_id[0] == INVALID_ENGINE ||
 						selected_id[1] == INVALID_ENGINE ||
 						selected_id[0] == selected_id[1] ||
 						EngineReplacementForPlayer(p, selected_id[1]) != INVALID_ENGINE ||
-						EngineReplacementForPlayer(p, selected_id[0]) == selected_id[1]) {
-					SETBIT(w->disabled_state, 4);
-				} else {
-					CLRBIT(w->disabled_state, 4);
-				}
+						EngineReplacementForPlayer(p, selected_id[0]) == selected_id[1]);
 
 				// Disable the "Stop Replacing" button if:
 				//    The left list (existing vehicle) is empty
 				// or The selected vehicle has no replacement set up
-				if (selected_id[0] == INVALID_ENGINE ||
-						!EngineHasReplacementForPlayer(p, selected_id[0])) {
-					SETBIT(w->disabled_state, 6);
-				} else {
-					CLRBIT(w->disabled_state, 6);
-				}
+				SetWindowWidgetDisabledState(w, 6,
+						selected_id[0] == INVALID_ENGINE ||
+						!EngineHasReplacementForPlayer(p, selected_id[0]));
 
 				// now the actual drawing of the window itself takes place
 				SetDParam(0, _vehicle_type_names[WP(w, replaceveh_d).vehicletype - VEH_Train]);
@@ -1577,7 +1571,7 @@
 
 	DrawWindowWidgets(w);
 
-	if (owner == _local_player && vl->l.list_length == 0) SETBIT(w->disabled_state, 9);
+	if (owner == _local_player && vl->l.list_length == 0) DisableWindowWidget(w, 9);
 
 	/* draw sorting criteria string */
 	DrawString(85, 15, _vehicle_sort_listing[vl->l.sort_type], 0x10);