Feature: Ctrl+Click to reset late counter for the entire vehicle group.

src/lang/english.txt

@@ -4529,7 +4529,7 @@ STR_TIMETABLE_CLEAR_SPEED                                       :{BLACK}Clear Sp
 STR_TIMETABLE_CLEAR_SPEED_TOOLTIP                               :{BLACK}Clear the maximum travel speed of the highlighted order. Ctrl+Click clears the speed for all orders
 
 STR_TIMETABLE_RESET_LATENESS                                    :{BLACK}Reset Late Counter
-STR_TIMETABLE_RESET_LATENESS_TOOLTIP                            :{BLACK}Reset the lateness counter, so the vehicle will be on time
+STR_TIMETABLE_RESET_LATENESS_TOOLTIP                            :{BLACK}Reset the lateness counter, so the vehicle will be on time. Ctrl+Click will reset the entire group so the latest vehicle will be on time and all others will be early
 
 STR_TIMETABLE_AUTOFILL                                          :{BLACK}Autofill
 STR_TIMETABLE_AUTOFILL_TOOLTIP                                  :{BLACK}Fill the timetable automatically with the values from the next journey. Ctrl+Click to try to keep waiting times

src/timetable_cmd.cpp

@@ -211,9 +211,10 @@ CommandCost CmdBulkChangeTimetable(DoCommandFlag flags, VehicleID veh, ModifyTim
  * Clear the lateness counter to make the vehicle on time.
  * @param flags Operation to perform.
  * @param veh Vehicle with the orders to change.
+ * @param apply_to_group Set to reset the late counter for all vehicles sharing the orders.
  * @return the cost of this operation or an error
  */
-CommandCost CmdSetVehicleOnTime(DoCommandFlag flags, VehicleID veh)
+CommandCost CmdSetVehicleOnTime(DoCommandFlag flags, VehicleID veh, bool apply_to_group)
 {
 	Vehicle *v = Vehicle::GetIfValid(veh);
 	if (v == nullptr || !v->IsPrimaryVehicle() || v->orders == nullptr) return CMD_ERROR;
@@ -222,8 +223,23 @@ CommandCost CmdSetVehicleOnTime(DoCommandFlag flags, VehicleID veh)
 	if (ret.Failed()) return ret;
 
 	if (flags & DC_EXEC) {
-		v->lateness_counter = 0;
-		SetWindowDirty(WC_VEHICLE_TIMETABLE, v->index);
+		if (apply_to_group) {
+			int32 most_late = 0;
+			for (Vehicle *u = v->FirstShared(); u != nullptr; u = u->NextShared()) {
+				if (u->lateness_counter > most_late) {
+					most_late = u->lateness_counter;
+				}
+			}
+			if (most_late > 0) {
+				for (Vehicle *u = v->FirstShared(); u != nullptr; u = u->NextShared()) {
+					u->lateness_counter -= most_late;
+					SetWindowDirty(WC_VEHICLE_TIMETABLE, u->index);
+				}
+			}
+		} else {
+			v->lateness_counter = 0;
+			SetWindowDirty(WC_VEHICLE_TIMETABLE, v->index);
+		}
 	}
 
 	return CommandCost();

src/timetable_cmd.h

@@ -14,7 +14,7 @@
 
 CommandCost CmdChangeTimetable(DoCommandFlag flags, VehicleID veh, VehicleOrderID order_number, ModifyTimetableFlags mtf, uint16 data);
 CommandCost CmdBulkChangeTimetable(DoCommandFlag flags, VehicleID veh, ModifyTimetableFlags mtf, uint16 data);
-CommandCost CmdSetVehicleOnTime(DoCommandFlag flags, VehicleID veh);
+CommandCost CmdSetVehicleOnTime(DoCommandFlag flags, VehicleID veh, bool apply_to_group);
 CommandCost CmdAutofillTimetable(DoCommandFlag flags, VehicleID veh, bool autofill, bool preserve_wait_time);
 CommandCost CmdSetTimetableStart(DoCommandFlag flags, VehicleID veh_id, bool timetable_all, Date start_date);
 

src/timetable_gui.cpp

@@ -600,7 +600,7 @@ struct TimetableWindow : Window {
 			}
 
 			case WID_VT_RESET_LATENESS: // Reset the vehicle's late counter.
-				Command<CMD_SET_VEHICLE_ON_TIME>::Post(STR_ERROR_CAN_T_TIMETABLE_VEHICLE, v->index);
+				Command<CMD_SET_VEHICLE_ON_TIME>::Post(STR_ERROR_CAN_T_TIMETABLE_VEHICLE, v->index, _ctrl_pressed);
 				break;
 
 			case WID_VT_AUTOFILL: { // Autofill the timetable.