Clamp hotbar selection to slots that exist (#14869)

doc/lua_api.md

@@ -8225,7 +8225,9 @@ child will follow movement and rotation of that bone.
     * See `hud_set_flags` for a list of flags that can be toggled.
 * `hud_set_hotbar_itemcount(count)`: sets number of items in builtin hotbar
     * `count`: number of items, must be between `1` and `32`
+    * If `count` exceeds the `"main"` list size, the list size will be used instead.
 * `hud_get_hotbar_itemcount()`: returns number of visible items
+    * This value is also clamped by the `"main"` list size.
 * `hud_set_hotbar_image(texturename)`
     * sets background image for hotbar
 * `hud_get_hotbar_image()`: returns texturename

games/devtest/mods/unittests/player.lua

@@ -84,3 +84,25 @@ local function run_player_add_pos_tests(player)
 end
 unittests.register("test_player_add_pos", run_player_add_pos_tests, {player=true})
 
+--
+-- Hotbar selection clamp
+--
+local function run_player_hotbar_clamp_tests(player)
+	local inv = player:get_inventory()
+	local old_inv_size = inv:get_size("main")
+	local old_inv_list = inv:get_list("main") -- Avoid accidentally removing item
+	local old_bar_size = player:hud_get_hotbar_itemcount()
+
+	inv:set_size("main", 5)
+
+	player:hud_set_hotbar_itemcount(2)
+	assert(player:hud_get_hotbar_itemcount() == 2)
+
+	player:hud_set_hotbar_itemcount(6)
+	assert(player:hud_get_hotbar_itemcount() == 5)
+
+	inv:set_size("main", old_inv_size)
+	inv:set_list("main", old_inv_list)
+	player:hud_set_hotbar_itemcount(old_bar_size)
+end
+unittests.register("test_player_hotbar_clamp", run_player_hotbar_clamp_tests, {player=true})

src/client/game.cpp

@@ -2188,12 +2188,14 @@ void Game::processItemSelection(u16 *new_playeritem)
 {
 	LocalPlayer *player = client->getEnv().getLocalPlayer();
 
+	*new_playeritem = player->getWieldIndex();
+	u16 max_item = player->getMaxHotbarItemcount();
+	if (max_item == 0)
+		return;
+	max_item -= 1;
+
 	/* Item selection using mouse wheel
 	 */
-	*new_playeritem = player->getWieldIndex();
-	u16 max_item = MYMIN(PLAYER_INVENTORY_SIZE - 1,
-		    player->hud_hotbar_itemcount - 1);
-
 	s32 wheel = input->getMouseWheel();
 	if (!m_enable_hotbar_mouse_wheel)
 		wheel = 0;

src/client/hud.cpp

@@ -783,7 +783,7 @@ void Hud::drawHotbar(u16 playeritem)
 
 	v2s32 centerlowerpos(m_displaycenter.X, m_screensize.Y);
 
-	s32 hotbar_itemcount = player->hud_hotbar_itemcount;
+	s32 hotbar_itemcount = player->getMaxHotbarItemcount();
 	s32 width = hotbar_itemcount * (m_hotbar_imagesize + m_padding * 2);
 	v2s32 pos = centerlowerpos - v2s32(width / 2, m_hotbar_imagesize + m_padding * 3);
 

src/network/serverpackethandler.cpp

@@ -852,11 +852,11 @@ void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
 
 	*pkt >> item;
 
-	if (item >= player->getHotbarItemcount()) {
+	if (item >= player->getMaxHotbarItemcount()) {
 		actionstream << "Player: " << player->getName()
 			<< " tried to access item=" << item
 			<< " out of hotbar_itemcount="
-			<< player->getHotbarItemcount()
+			<< player->getMaxHotbarItemcount()
 			<< "; ignoring." << std::endl;
 		return;
 	}
@@ -983,11 +983,11 @@ void Server::handleCommand_Interact(NetworkPacket *pkt)
 
 	// Update wielded item
 
-	if (item_i >= player->getHotbarItemcount()) {
+	if (item_i >= player->getMaxHotbarItemcount()) {
 		actionstream << "Player: " << player->getName()
 			<< " tried to access item=" << item_i
 			<< " out of hotbar_itemcount="
-			<< player->getHotbarItemcount()
+			<< player->getMaxHotbarItemcount()
 			<< "; ignoring." << std::endl;
 		return;
 	}

src/player.cpp

@@ -88,6 +88,11 @@ void Player::setWieldIndex(u16 index)
 	m_wield_index = MYMIN(index, mlist ? mlist->getSize() : 0);
 }
 
+u16 Player::getWieldIndex()
+{
+	return std::min(m_wield_index, getMaxHotbarItemcount());
+}
+
 ItemStack &Player::getWieldedItem(ItemStack *selected, ItemStack *hand) const
 {
 	assert(selected);
@@ -157,6 +162,12 @@ void Player::clearHud()
 	}
 }
 
+u16 Player::getMaxHotbarItemcount()
+{
+	InventoryList *mainlist = inventory.getList("main");
+	return mainlist ? std::min(mainlist->getSize(), (u32) hud_hotbar_itemcount) : 0;
+}
+
 #ifndef SERVER
 
 u32 PlayerControl::getKeysPressed() const

src/player.h

@@ -223,7 +223,7 @@ public:
 	// Returns non-empty `selected` ItemStack. `hand` is a fallback, if specified
 	ItemStack &getWieldedItem(ItemStack *selected, ItemStack *hand) const;
 	void setWieldIndex(u16 index);
-	u16 getWieldIndex() const { return m_wield_index; }
+	u16 getWieldIndex();
 
 	bool setFov(const PlayerFovSpec &spec)
 	{
@@ -247,6 +247,9 @@ public:
 	u32 hud_flags;
 	s32 hud_hotbar_itemcount;
 
+	// Get actual usable number of hotbar items (clamped to size of "main" list)
+	u16 getMaxHotbarItemcount();
+
 protected:
 	char m_name[PLAYERNAME_SIZE];
 	v3f m_speed; // velocity; in BS-space

src/script/lua_api/l_object.cpp

@@ -1842,7 +1842,7 @@ int ObjectRef::l_hud_get_hotbar_itemcount(lua_State *L)
 	if (player == nullptr)
 		return 0;
 
-	lua_pushinteger(L, player->getHotbarItemcount());
+	lua_pushinteger(L, player->getMaxHotbarItemcount());
 	return 1;
 }