Add new hotbar_slot_selected lua callback

builtin/game/register.lua

@@ -618,6 +618,7 @@ core.registered_allow_player_inventory_actions, core.register_allow_player_inven
 core.registered_on_rightclickplayers, core.register_on_rightclickplayer = make_registration()
 core.registered_on_liquid_transformed, core.register_on_liquid_transformed = make_registration()
 core.registered_on_mapblocks_changed, core.register_on_mapblocks_changed = make_registration()
+core.registered_on_hotbar_slot_selected, core.register_on_hotbar_slot_selected = make_registration()
 
 -- A bunch of registrations are read by the C++ side once on env init, so we cannot
 -- allow them to change afterwards (see s_env.cpp).

doc/lua_api.md

@@ -6331,6 +6331,14 @@ Call these functions only at load time!
       The set is a table where the keys are hashes and the values are `true`.
     * `modified_block_count` is the number of entries in the set.
     * Note: callbacks must be registered at mod load time.
+* `core.register_on_hotbar_slot_selected(function(player, inventory, list_name, hotbar_slot, prev_hotbar_slot, is_from_scrolling))`
+    * Called when the player selects a hotbar slot, including re-selecting current slot
+    * `player`: `ObjectRef` - Player that selected their hotbar slot
+    * `inventory`: type `InvRef`
+    * `list_name`: string - the name of the hotbar list
+    * `hotbar_slot`: integer - the newly selected hotbar slot
+    * `prev_hotbar_slot`: integer - the previously selected hotbar slot, can be the same as `hotbar_slot` if the player selected the same slot
+    * `is_from_scrolling`: boolean - true if the input came from a scroll action, or the prev/next slot input keys
 
 Setting-related
 ---------------
@@ -7890,6 +7898,7 @@ For historical reasons, the use of an -s suffix in these names is inconsistent.
 * `core.registered_on_modchannel_message`
 * `core.registered_on_liquid_transformed`
 * `core.registered_on_mapblocks_changed`
+* `core.registered_on_hotbar_slot_selected`
 
 Class reference
 ===============

src/client/game.cpp

@@ -2036,6 +2036,9 @@ void Game::processItemSelection(u16 *new_playeritem)
 	if (max_item == 0)
 		return;
 	max_item -= 1;
+	u16 prev_playeritem = *new_playeritem;
+	bool player_input_happened = false;
+	bool change_was_from_scrolling = false;
 
 	/* Item selection using mouse wheel
 	 */
@@ -2053,6 +2056,10 @@ void Game::processItemSelection(u16 *new_playeritem)
 	if (wasKeyDown(KeyType::HOTBAR_PREV))
 		dir = 1;
 
+	if (dir != 0) {
+		player_input_happened = true;
+		change_was_from_scrolling = true;
+	}
 	if (dir < 0)
 		*new_playeritem = *new_playeritem < max_item ? *new_playeritem + 1 : 0;
 	else if (dir > 0)
@@ -2064,18 +2071,37 @@ void Game::processItemSelection(u16 *new_playeritem)
 	for (u16 i = 0; i <= max_item; i++) {
 		if (wasKeyDown((GameKeyType) (KeyType::SLOT_1 + i))) {
 			*new_playeritem = i;
+			player_input_happened = true;
+			change_was_from_scrolling = false;
 			break;
 		}
 	}
 
 	if (g_touchcontrols) {
 		std::optional<u16> selection = g_touchcontrols->getHotbarSelection();
-		if (selection)
+		if (selection) {
 			*new_playeritem = *selection;
+			player_input_happened = true;
+			change_was_from_scrolling = false;
+		}
 	}
 
 	// Clamp selection again in case it wasn't changed but max_item was
 	*new_playeritem = MYMIN(*new_playeritem, max_item);
+
+	if (player_input_happened) {
+		if (prev_playeritem != *new_playeritem) {
+			client->setPlayerItem(*new_playeritem);
+		}
+		// notify server of hotbar item selected
+		IHotbarSlotSelectedAction* a = new IHotbarSlotSelectedAction();
+		a->inv.setCurrentPlayer();
+		a->list = "main";
+		a->selected_slot = *new_playeritem;
+		a->prev_selected_slot = prev_playeritem;
+		a->from_scroll = change_was_from_scrolling;
+		client->inventoryAction(a);
+	}
 }
 
 

src/inventorymanager.cpp

@@ -104,6 +104,8 @@ InventoryAction *InventoryAction::deSerialize(std::istream &is)
 		a = new IDropAction(is);
 	} else if (type == "Craft") {
 		a = new ICraftAction(is);
+	} else if (type == "HotbarSlotSelected") {
+		a = new IHotbarSlotSelectedAction(is);
 	}
 
 	return a;
@@ -1017,3 +1019,54 @@ bool getCraftingResult(Inventory *inv, ItemStack &result,
 	return found;
 }
 
+/*
+	IHotbarSlotSelectedAction
+*/
+
+IHotbarSlotSelectedAction::IHotbarSlotSelectedAction(std::istream& is)
+{
+	std::string ts;
+
+	std::getline(is, ts, ' ');
+	inv.deSerialize(ts);
+
+	std::getline(is, list, ' ');
+
+	std::getline(is, ts, ' ');
+	selected_slot = stoi(ts);
+
+	std::getline(is, ts, ' ');
+	prev_selected_slot = stoi(ts);
+
+	std::getline(is, ts, ' ');
+	from_scroll = stoi(ts);
+}
+
+void IHotbarSlotSelectedAction::apply(InventoryManager* mgr, ServerActiveObject* player, IGameDef* gamedef)
+{
+	Inventory* inv_hotbar = mgr->getInventory(inv);
+
+	if (!inv_hotbar) {
+		warningstream << "IHotbarSlotSelectedAction::apply(): FAIL: source inventory not found: "
+			<< "inv=\"" << inv.dump() << "\"" << std::endl;
+		return;
+	}
+
+	InventoryList* list_wield = inv_hotbar->getList(list);
+
+	/*
+		If the list doesn't exist
+	*/
+	if (!list_wield) {
+		warningstream << "IHotbarSlotSelectedAction::apply(): FAIL: source list not found: "
+			<< "list=\"" << list << "\"" << std::endl;
+		return;
+	}
+	ServerScripting* sa = PLAYER_TO_SA(player);
+	sa->on_hotbar_slot_selected(player, inv, list, selected_slot, prev_selected_slot, from_scroll);
+}
+
+void IHotbarSlotSelectedAction::clientApply(InventoryManager* mgr, IGameDef* gamedef)
+{
+	// Optional operation that is run on the client to make lag less apparent.
+}

src/inventorymanager.h

@@ -109,7 +109,8 @@ public:
 enum class IAction : u16 {
 	Move,
 	Drop,
-	Craft
+	Craft,
+	HotbarSlotSelected,
 };
 
 struct InventoryAction
@@ -247,3 +248,35 @@ struct ICraftAction : public InventoryAction
 bool getCraftingResult(Inventory *inv, ItemStack &result,
 		std::vector<ItemStack> &output_replacements,
 		bool decrementInput, IGameDef *gamedef);
+
+struct IHotbarSlotSelectedAction : public InventoryAction
+{
+	InventoryLocation inv;
+	std::string list;
+	s16 selected_slot = -1;
+	s16 prev_selected_slot = -1;
+	bool from_scroll = false;
+
+	IHotbarSlotSelectedAction() = default;
+
+	IHotbarSlotSelectedAction(std::istream& is);
+
+	IAction getType() const
+	{
+		return IAction::HotbarSlotSelected;
+	}
+
+	void serialize(std::ostream& os) const
+	{
+		os<<"HotbarSlotSelected ";
+		os<<inv.dump()<<" ";
+		os<<list<<" ";
+		os<<selected_slot<<" ";
+		os<<prev_selected_slot<<" ";
+		os<<(from_scroll ? "1" : "0");
+	}
+
+	void apply(InventoryManager* mgr, ServerActiveObject* player, IGameDef* gamedef);
+
+	void clientApply(InventoryManager* mgr, IGameDef* gamedef);
+};

src/network/serverpackethandler.cpp

@@ -734,6 +734,14 @@ void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
 
 		if (!check_inv_access(ca->craft_inv))
 			return;
+	}
+	/*
+		Handle HotbarSlotSelected action special cases
+	*/
+	else if (a->getType() == IAction::HotbarSlotSelected) {
+		IHotbarSlotSelectedAction *ha = (IHotbarSlotSelectedAction*)a.get();
+		ha->inv.applyCurrentPlayer(player->getName());
+		// Note: `IHotbarSlotSelectedAction::clientApply` is empty, thus nothing to revert.
 	} else {
 		// Unknown action. Ignored.
 		return;

src/script/cpp_api/s_player.cpp

@@ -236,6 +236,35 @@ void ScriptApiPlayer::on_authplayer(const std::string &name, const std::string &
 	runCallbacks(3, RUN_CALLBACKS_MODE_FIRST);
 }
 
+void ScriptApiPlayer::on_hotbar_slot_selected(
+	ServerActiveObject* player,
+	InventoryLocation& loc,
+	const std::string &list,
+	int hotbar_slot,
+	int prev_hotbar_slot,
+	bool is_from_scroll
+)
+{
+	SCRIPTAPI_PRECHECKHEADER
+
+	lua_getglobal(L, "core");
+	lua_getfield(L, -1, "registered_on_hotbar_slot_selected");
+	// param 1
+	objectrefGetOrCreate(L, player);
+	// param 2
+	InvRef::create(L, loc);
+	// param 3
+	lua_pushstring(L, list.c_str());
+	// param 4
+	lua_pushinteger(L, hotbar_slot + 1);
+	// param 5
+	lua_pushinteger(L, prev_hotbar_slot + 1);
+	// param 6
+	lua_pushboolean(L, is_from_scroll);
+
+	runCallbacks(6, RUN_CALLBACKS_MODE_LAST);
+}
+
 void ScriptApiPlayer::pushMoveArguments(
 		const MoveAction &ma, int count,
 		ServerActiveObject *player)

src/script/cpp_api/s_player.h

@@ -38,6 +38,14 @@ public:
 	void on_playerReceiveFields(ServerActiveObject *player,
 			const std::string &formname, const StringMap &fields);
 	void on_authplayer(const std::string &name, const std::string &ip, bool is_success);
+	void on_hotbar_slot_selected(
+		ServerActiveObject* player,
+		InventoryLocation& loc,
+		const std::string& list,
+		int hotbar_slot,
+		int prev_hotbar_slot,
+		bool is_from_scroll
+	);
 
 	// Player inventory callbacks
 	// Return number of accepted items to be moved