Add information about vehicle loads and speeds

src/lang/english.txt

@@ -4965,6 +4965,9 @@ STR_VEHICLE_DETAILS_CARGO_EMPTY                                 :{LTBLUE}Empty
 STR_VEHICLE_DETAILS_CARGO_FROM                                  :{LTBLUE}{CARGO_LONG} from {STATION}
 STR_VEHICLE_DETAILS_CARGO_FROM_MULT                             :{LTBLUE}{CARGO_LONG} from {STATION} (x{NUM})
 
+STR_VEHICLE_DETAILS_TRAIN_TOTAL_WEIGHT                          :{BLACK}Total weight: {LTBLUE}{WEIGHT_SHORT} (empty) - {LTBLUE}{WEIGHT_SHORT} (loaded)
+STR_VEHICLE_DETAILS_TRAIN_MAX_SPEED                             :{BLACK}Max. speed: {LTBLUE}{VELOCITY} (empty) - {LTBLUE}{VELOCITY} (loaded)
+
 STR_VEHICLE_DETAIL_TAB_CARGO                                    :{BLACK}Cargo
 STR_VEHICLE_DETAILS_TRAIN_CARGO_TOOLTIP                         :{BLACK}Show details of cargo carried
 STR_VEHICLE_DETAIL_TAB_INFORMATION                              :{BLACK}Information

src/train.h

@@ -276,6 +276,48 @@ public:
 		}
 	}
 
+	/**
+	* Gets the weight of this vehicle when empty.
+	* @return Empty weight in tonnes.
+	*/
+	uint16 GetEmptyWeight() const
+	{
+		uint16 weight = 0;
+
+		/* Vehicle weight is not added for articulated parts. */
+		if (!this->IsArticulatedPart()) {
+			weight += GetVehicleProperty(this, PROP_TRAIN_WEIGHT, RailVehInfo(this->engine_type)->weight);
+		}
+
+		/* Powered wagons have extra weight added. */
+		if (HasBit(this->flags, VRF_POWEREDWAGON)) {
+			weight += RailVehInfo(this->gcache.first_engine)->pow_wag_weight;
+		}
+
+		return weight * (this->IsWagon() ? FreightWagonMult(this->cargo_type) : 1);
+	}
+
+	/**
+	* Gets the weight of this vehicle when fully loaded.
+	* @return Loaded weight in tonnes.
+	*/
+	uint16 GetLoadedWeight() const
+	{
+		uint16 weight = (CargoSpec::Get(this->cargo_type)->weight * this->cargo_cap) / 16;
+
+		/* Vehicle weight is not added for articulated parts. */
+		if (!this->IsArticulatedPart()) {
+			weight += GetVehicleProperty(this, PROP_TRAIN_WEIGHT, RailVehInfo(this->engine_type)->weight);
+		}
+
+		/* Powered wagons have extra weight added. */
+		if (HasBit(this->flags, VRF_POWEREDWAGON)) {
+			weight += RailVehInfo(this->gcache.first_engine)->pow_wag_weight;
+		}
+
+		return weight * (this->IsWagon() ? FreightWagonMult(this->cargo_type) : 1);
+	}
+
 protected: // These functions should not be called outside acceleration code.
 	/**
 	 * Gets the speed a broken down train (low speed breakdown) is limited to.

src/train_gui.cpp

@@ -390,7 +390,7 @@ int GetTrainDetailsWndVScroll(VehicleID veh_id, TrainDetailsWindowTabs det_tab)
 		for (CargoID i = 0; i < NUM_CARGO; i++) {
 			if (max_cargo[i] > 0) num++; // only count carriages that the train has
 		}
-		num++; // needs one more because first line is description string
+		num += 5; // needs five more because first line is description string and we have the weight and speed info
 	} else {
 		for (const Train *v = Train::Get(veh_id); v != nullptr; v = v->GetNextVehicle()) {
 			GetCargoSummaryOfArticulatedVehicle(v, &_cargo_summary);
@@ -512,19 +512,52 @@ void DrawTrainDetails(const Train *v, int left, int right, int y, int vscroll_po
 		CargoArray act_cargo;
 		CargoArray max_cargo;
 		Money feeder_share = 0;
+		uint16 empty_weight = 0;
+		uint16 loaded_weight = 0;
+		uint16 empty_max_speed = 0;
+		uint16 loaded_max_speed = 0;
 
 		for (const Vehicle *u = v; u != nullptr; u = u->Next()) {
 			act_cargo[u->cargo_type] += u->cargo.StoredCount();
 			max_cargo[u->cargo_type] += u->cargo_cap;
 			feeder_share             += u->cargo.FeederShare();
+			empty_weight             += Train::From(u)->GetEmptyWeight();
+			loaded_weight            += Train::From(u)->GetLoadedWeight();
 		}
 
-		/* draw total cargo tab */
+		const auto rolling_friction = 15 * (512 + v->GetDisplayMaxSpeed()) / 512;
-		DrawString(left, right, y + text_y_offset, STR_VEHICLE_DETAILS_TRAIN_TOTAL_CAPACITY_TEXT);
+		const auto tractive_effort_empty = empty_weight * rolling_friction;
-		y += line_height;
+		const auto tractive_effort_loaded = loaded_weight * rolling_friction;
+		const auto power = v->gcache.cached_power * 746ll;
+		const auto max_te = v->gcache.cached_max_te;
+		empty_max_speed = std::min<uint16>(v->GetDisplayMaxSpeed(), (tractive_effort_empty == 0 || tractive_effort_empty > max_te) ? 0 : (3.6 * (power / tractive_effort_empty)));
+		loaded_max_speed = std::min<uint16>(v->GetDisplayMaxSpeed(), (tractive_effort_loaded == 0 || tractive_effort_loaded > max_te) ? 0 : (3.6 * (power / tractive_effort_loaded)));
+
+		if (--vscroll_pos < 0 && vscroll_pos >= -vscroll_cap) {
+			SetDParam(0, empty_weight);
+			SetDParam(1, loaded_weight);
+			DrawString(left, right, y + text_y_offset, STR_VEHICLE_DETAILS_TRAIN_TOTAL_WEIGHT);
+			y += line_height;
+		}
+
+		if (--vscroll_pos < 0 && vscroll_pos >= -vscroll_cap) {
+			SetDParam(0, empty_max_speed);
+			SetDParam(1, loaded_max_speed);
+			DrawString(left, right, y + text_y_offset, STR_VEHICLE_DETAILS_TRAIN_MAX_SPEED);
+			y += line_height;
+		}
+
+		if (--vscroll_pos < 0 && vscroll_pos >= -vscroll_cap) {
+			y += line_height;
+		}
+
+		if (--vscroll_pos < 0 && vscroll_pos >= -vscroll_cap) {
+			DrawString(left, right, y + text_y_offset, STR_VEHICLE_DETAILS_TRAIN_TOTAL_CAPACITY_TEXT);
+			y += line_height;
+		}
 
 		for (CargoID i = 0; i < NUM_CARGO; i++) {
-			if (max_cargo[i] > 0 && --vscroll_pos < 0 && vscroll_pos > -vscroll_cap) {
+			if (max_cargo[i] > 0 && --vscroll_pos < 0 && vscroll_pos >= -vscroll_cap) {
 				SetDParam(0, i);            // {CARGO} #1
 				SetDParam(1, act_cargo[i]); // {CARGO} #2
 				SetDParam(2, i);            // {SHORTCARGO} #1
@@ -534,7 +567,16 @@ void DrawTrainDetails(const Train *v, int left, int right, int y, int vscroll_po
 				y += line_height;
 			}
 		}
-		SetDParam(0, feeder_share);
+
-		DrawString(left, right, y + text_y_offset, STR_VEHICLE_INFO_FEEDER_CARGO_VALUE);
+		for (const Vehicle *u = v; u != nullptr; u = u->Next()) {
+			act_cargo[u->cargo_type] += u->cargo.StoredCount();
+			max_cargo[u->cargo_type] += u->cargo_cap;
+			feeder_share             += u->cargo.FeederShare();
+		}
+
+		if (--vscroll_pos < 0 && vscroll_pos >= -vscroll_cap) {
+			SetDParam(0, feeder_share);
+			DrawString(left, right, y + text_y_offset, STR_VEHICLE_INFO_FEEDER_CARGO_VALUE);
+		}
 	}
 }