Add: Overlay cargo icon in vehicle/depot list when holding shift+ctrl. (#12938)

src/aircraft_gui.cpp

@@ -97,6 +97,17 @@ void DrawAircraftImage(const Vehicle *v, const Rect &r, VehicleID selection, Eng
 
 	PaletteID pal = (v->vehstatus & VS_CRASHED) ? PALETTE_CRASH : GetVehiclePalette(v);
 	seq.Draw(x, y, pal, (v->vehstatus & VS_CRASHED) != 0);
+
+	/* Aircraft can store cargo in their shadow, show this if present. */
+	const Vehicle *u = v->Next();
+	assert(u != nullptr);
+	int dx = 0;
+	if (u->cargo_cap > 0 && u->cargo_type != v->cargo_type) {
+		dx = GetLargestCargoIconSize().width / 2;
+		DrawCargoIconOverlay(x + dx, y, u->cargo_type);
+	}
+	if (v->cargo_cap > 0) DrawCargoIconOverlay(x - dx, y, v->cargo_type);
+
 	if (helicopter) {
 		const Aircraft *a = Aircraft::From(v);
 		VehicleSpriteSeq rotor_seq;

src/depot_gui.cpp

@@ -974,6 +974,15 @@ struct DepotWindow : Window {
 		}
 	}
 
+	bool last_overlay_state;
+	void OnMouseLoop() override
+	{
+		if (last_overlay_state != ShowCargoIconOverlay()) {
+			last_overlay_state = ShowCargoIconOverlay();
+			this->SetDirty();
+		}
+	}
+
 	void OnMouseDrag(Point pt, WidgetID widget) override
 	{
 		if (this->sel == INVALID_VEHICLE) return;

src/group_gui.cpp

@@ -692,6 +692,15 @@ public:
 		}
 	}
 
+	bool last_overlay_state;
+	void OnMouseLoop() override
+	{
+		if (last_overlay_state != ShowCargoIconOverlay()) {
+			last_overlay_state = ShowCargoIconOverlay();
+			this->SetDirty();
+		}
+	}
+
 	void OnClick([[maybe_unused]] Point pt, WidgetID widget, [[maybe_unused]] int click_count) override
 	{
 		switch (widget) {

src/lang/english.txt

@@ -4009,10 +4009,10 @@ STR_VEHICLE_LIST_SHIP_CAPTION                                   :{WHITE}{STRING2
 STR_VEHICLE_LIST_AIRCRAFT_CAPTION                               :{WHITE}{STRING2} - {COMMA} Aircraft
 
 ###length VEHICLE_TYPES
-STR_VEHICLE_LIST_TRAIN_LIST_TOOLTIP                             :{BLACK}Trains - click on train for information
+STR_VEHICLE_LIST_TRAIN_LIST_TOOLTIP                             :{BLACK}Trains - click on train for information. Hold Ctrl+Shift to overlay cargo type
-STR_VEHICLE_LIST_ROAD_VEHICLE_TOOLTIP                           :{BLACK}Road vehicles - click on vehicle for information
+STR_VEHICLE_LIST_ROAD_VEHICLE_TOOLTIP                           :{BLACK}Road vehicles - click on vehicle for information. Hold Ctrl+Shift to overlay cargo type
-STR_VEHICLE_LIST_SHIP_TOOLTIP                                   :{BLACK}Ships - click on ship for information
+STR_VEHICLE_LIST_SHIP_TOOLTIP                                   :{BLACK}Ships - click on ship for information. Hold Ctrl+Shift to overlay cargo type
-STR_VEHICLE_LIST_AIRCRAFT_TOOLTIP                               :{BLACK}Aircraft - click on aircraft for information
+STR_VEHICLE_LIST_AIRCRAFT_TOOLTIP                               :{BLACK}Aircraft - click on aircraft for information. Hold Ctrl+Shift to overlay cargo type
 
 ###length VEHICLE_TYPES
 STR_VEHICLE_LIST_AVAILABLE_TRAINS                               :Available Trains

src/roadveh_gui.cpp

@@ -132,6 +132,10 @@ void DrawRoadVehImage(const Vehicle *v, const Rect &r, VehicleID selection, Engi
 
 	AutoRestoreBackup dpi_backup(_cur_dpi, &tmp_dpi);
 
+	bool do_overlays = ShowCargoIconOverlay();
+	/* List of overlays, only used if cargo icon overlays are enabled. */
+	static std::vector<CargoIconOverlay> overlays;
+
 	int px = rtl ? max_width + skip : -skip;
 	int y = r.Height() / 2;
 	for (; u != nullptr && (rtl ? px > 0 : px < max_width); u = u->Next())
@@ -146,9 +150,15 @@ void DrawRoadVehImage(const Vehicle *v, const Rect &r, VehicleID selection, Engi
 			seq.Draw(px + (rtl ? -offset.x : offset.x), y + offset.y, pal, (u->vehstatus & VS_CRASHED) != 0);
 		}
 
+		if (do_overlays) AddCargoIconOverlay(overlays, px, width, u);
 		px += rtl ? -width : width;
 	}
 
+	if (do_overlays) {
+		DrawCargoIconOverlays(overlays, y);
+		overlays.clear();
+	}
+
 	if (v->index == selection) {
 		int height = ScaleSpriteTrad(12);
 		Rect hr = {(rtl ? px : 0), 0, (rtl ? max_width : px) - 1, height - 1};

src/ship_gui.cpp

@@ -44,6 +44,7 @@ void DrawShipImage(const Vehicle *v, const Rect &r, VehicleID selection, EngineI
 	int y = ScaleSpriteTrad(-1) + CenterBounds(r.top, r.bottom, 0);
 
 	seq.Draw(x, y, GetVehiclePalette(v), false);
+	if (v->cargo_cap > 0) DrawCargoIconOverlay(x, y, v->cargo_type);
 
 	if (v->index == selection) {
 		x += x_offs;

src/train_gui.cpp

@@ -106,6 +106,10 @@ void DrawTrainImage(const Train *v, const Rect &r, VehicleID selection, EngineIm
 	{
 		AutoRestoreBackup dpi_backup(_cur_dpi, &tmp_dpi);
 
+		bool do_overlays = ShowCargoIconOverlay();
+		/* List of overlays, only used if cargo icon overlays are enabled. */
+		static std::vector<CargoIconOverlay> overlays;
+
 		int px = rtl ? max_width + skip : -skip;
 		int y = r.Height() / 2;
 		bool sel_articulated = false;
@@ -143,9 +147,15 @@ void DrawTrainImage(const Train *v, const Rect &r, VehicleID selection, EngineIm
 				}
 			}
 
+			if (do_overlays) AddCargoIconOverlay(overlays, px, width, v);
 			px += rtl ? -width : width;
 		}
 
+		if (do_overlays) {
+			DrawCargoIconOverlays(overlays, y);
+			overlays.clear();
+		}
+
 		if (dragging && drag_at_end_of_train) {
 			/* Highlight the drag-and-drop destination at the end of the train. */
 			HighlightDragPosition(px, max_width, y, selection, _cursor.vehchain);

src/vehicle_gui.cpp

@@ -329,6 +329,82 @@ static bool CargoFilter(const GUIVehicleGroup *vehgroup, const CargoID cid)
 	return false;
 }
 
+/**
+ * Test if cargo icon overlays should be drawn.
+ * @returns true iff cargo icon overlays should be drawn.
+ */
+bool ShowCargoIconOverlay()
+{
+	return _shift_pressed && _ctrl_pressed;
+}
+
+/**
+ * Add a cargo icon to the list of overlays.
+ * @param overlays List of overlays.
+ * @param x Horizontal position.
+ * @param width Width available.
+ * @param v Vehicle to add.
+ */
+void AddCargoIconOverlay(std::vector<CargoIconOverlay> &overlays, int x, int width, const Vehicle *v)
+{
+	bool rtl = _current_text_dir == TD_RTL;
+	if (!v->IsArticulatedPart() || v->cargo_type != v->Previous()->cargo_type) {
+		/* Add new overlay slot. */
+		overlays.emplace_back(rtl ? x - width : x, rtl ? x : x + width, v->cargo_type, v->cargo_cap);
+	} else {
+		/* This is an articulated part with the same cargo type, adjust left or right of last overlay slot. */
+		if (rtl) {
+			overlays.back().left -= width;
+		} else {
+			overlays.back().right += width;
+		}
+		overlays.back().cargo_cap += v->cargo_cap;
+	}
+}
+
+/**
+ * Draw a cargo icon overlaying an existing sprite, with a black contrast outline.
+ * @param x Horizontal position from left.
+ * @param y Vertical position from top.
+ * @param cid Cargo ID to draw icon for.
+ */
+void DrawCargoIconOverlay(int x, int y, CargoID cid)
+{
+	if (!ShowCargoIconOverlay()) return;
+	if (!IsValidCargoID(cid)) return;
+
+	const CargoSpec *cs = CargoSpec::Get(cid);
+
+	SpriteID spr = cs->GetCargoIcon();
+	if (spr == 0) return;
+
+	Dimension d = GetSpriteSize(spr);
+	d.width /= 2;
+	d.height /= 2;
+	int one = ScaleGUITrad(1);
+
+	/* Draw the cargo icon in black shifted 4 times to create the outline. */
+	DrawSprite(spr, PALETTE_ALL_BLACK, x - d.width - one, y - d.height);
+	DrawSprite(spr, PALETTE_ALL_BLACK, x - d.width + one, y - d.height);
+	DrawSprite(spr, PALETTE_ALL_BLACK, x - d.width, y - d.height - one);
+	DrawSprite(spr, PALETTE_ALL_BLACK, x - d.width, y - d.height + one);
+	/* Draw the cargo icon normally. */
+	DrawSprite(spr, PAL_NONE, x - d.width, y - d.height);
+}
+
+/**
+ * Draw a list of cargo icon overlays.
+ * @param overlays List of overlays.
+ * @param y Vertical position.
+ */
+void DrawCargoIconOverlays(std::span<const CargoIconOverlay> overlays, int y)
+{
+	for (const auto &cio : overlays) {
+		if (cio.cargo_cap == 0) continue;
+		DrawCargoIconOverlay((cio.left + cio.right) / 2, y, cio.cargo_type);
+	}
+}
+
 static GUIVehicleGroupList::FilterFunction * const _vehicle_group_filter_funcs[] = {
 	&CargoFilter,
 };
@@ -2053,6 +2129,15 @@ public:
 		this->DrawWidgets();
 	}
 
+	bool last_overlay_state;
+	void OnMouseLoop() override
+	{
+		if (last_overlay_state != ShowCargoIconOverlay()) {
+			last_overlay_state = ShowCargoIconOverlay();
+			this->SetDirty();
+		}
+	}
+
 	void OnClick([[maybe_unused]] Point pt, WidgetID widget, [[maybe_unused]] int click_count) override
 	{
 		switch (widget) {

src/vehicle_gui_base.h

@@ -139,6 +139,22 @@ struct BaseVehicleListWindow : public Window {
 	}
 };
 
+struct CargoIconOverlay {
+	int left;
+	int right;
+	CargoID cargo_type;
+	uint cargo_cap;
+
+	constexpr CargoIconOverlay(int left, int right, CargoID cargo_type, uint cargo_cap)
+		: left(left), right(right), cargo_type(cargo_type), cargo_cap(cargo_cap)
+	{ }
+};
+
+bool ShowCargoIconOverlay();
+void AddCargoIconOverlay(std::vector<CargoIconOverlay> &overlays, int x, int width, const Vehicle *v);
+void DrawCargoIconOverlay(int x, int y, CargoID cid);
+void DrawCargoIconOverlays(std::span<const CargoIconOverlay> overlays, int y);
+
 uint GetVehicleListHeight(VehicleType type, uint divisor = 1);
 
 struct Sorting {