Automatic item and node colorization (#5640)

* Automatic item and node colorization

Now nodes with a palette yield colored item stacks, and colored items
place colored nodes by default. The client predicts the colorization.

* Backwards compatibility

* Use nil

* Style fixes

* Fix code style

* Document changes

8 files changed, 114 insertions, 38 deletions

diff --git a/builtin/game/falling.lua b/builtin/game/falling.lua
index b1beb1ab0..1ac4f7081 100644
--- a/builtin/game/falling.lua
+++ b/builtin/game/falling.lua
@@ -93,7 +93,7 @@ core.register_entity(":__builtin:falling_node", {
 				core.remove_node(np)
 				if nd and nd.buildable_to == false then
 					-- Add dropped items
-					local drops = core.get_node_drops(n2.name, "")
+					local drops = core.get_node_drops(n2, "")
 					for _, dropped_item in pairs(drops) do
 						core.add_item(np, dropped_item)
 					end
@@ -145,9 +145,9 @@ function core.spawn_falling_node(pos)
 end
 
 local function drop_attached_node(p)
-	local nn = core.get_node(p).name
+	local n = core.get_node(p)
 	core.remove_node(p)
-	for _, item in pairs(core.get_node_drops(nn, "")) do
+	for _, item in pairs(core.get_node_drops(n, "")) do
 		local pos = {
 			x = p.x + math.random()/2 - 0.25,
 			y = p.y + math.random()/2 - 0.25,
diff --git a/builtin/game/item.lua b/builtin/game/item.lua
index e36745f93..f6de2c339 100644
--- a/builtin/game/item.lua
+++ b/builtin/game/item.lua
@@ -155,12 +155,35 @@ function core.yaw_to_dir(yaw)
 	return {x = -math.sin(yaw), y = 0, z = math.cos(yaw)}
 end
 
-function core.get_node_drops(nodename, toolname)
+function core.get_node_drops(node, toolname)
+	-- Compatibility, if node is string
+	local nodename = node
+	local param2 = 0
+	-- New format, if node is table
+	if (type(node) == "table") then
+		nodename = node.name
+		param2 = node.param2
+	end
 	local def = core.registered_nodes[nodename]
 	local drop = def and def.drop
 	if drop == nil then
 		-- default drop
-		return {nodename}
+		local stack = ItemStack(nodename)
+		if def then
+			local type = def.paramtype2
+			if (type == "color") or (type == "colorfacedir") or
+					(type == "colorwallmounted") then
+				local meta = stack:get_meta()
+				local color_part = param2
+				if (type == "colorfacedir") then
+					color_part = math.floor(color_part / 32) * 32;
+				elseif (type == "colorwallmounted") then
+					color_part = math.floor(color_part / 8) * 8;
+				end
+				meta:set_int("palette_index", color_part)
+			end
+		end
+		return {stack:to_string()}
 	elseif type(drop) == "string" then
 		-- itemstring drop
 		return {drop}
@@ -258,7 +281,7 @@ function core.item_place_node(itemstack, placer, pointed_thing, param2)
 		.. def.name .. " at " .. core.pos_to_string(place_to))
 
 	local oldnode = core.get_node(place_to)
-	local newnode = {name = def.name, param1 = 0, param2 = param2}
+	local newnode = {name = def.name, param1 = 0, param2 = param2 or 0}
 
 	-- Calculate direction for wall mounted stuff like torches and signs
 	if def.place_param2 ~= nil then
@@ -286,6 +309,25 @@ function core.item_place_node(itemstack, placer, pointed_thing, param2)
 		end
 	end
 
+	local metatable = itemstack:get_meta():to_table().fields
+
+	-- Transfer color information
+	if metatable.palette_index and not def.place_param2 then
+		local color_divisor = nil
+		if def.paramtype2 == "color" then
+			color_divisor = 1
+		elseif def.paramtype2 == "colorwallmounted" then
+			color_divisor = 8
+		elseif def.paramtype2 == "colorfacedir" then
+			color_divisor = 32
+		end
+		if color_divisor then
+			local color = math.floor(metatable.palette_index / color_divisor)
+			local other = newnode.param2 % color_divisor
+			newnode.param2 = color * color_divisor + other
+		end
+	end
+
 	-- Check if the node is attached and if it can be placed there
 	if core.get_item_group(def.name, "attached_node") ~= 0 and
 		not builtin_shared.check_attached_node(place_to, newnode) then
@@ -474,7 +516,7 @@ function core.node_dig(pos, node, digger)
 		.. node.name .. " at " .. core.pos_to_string(pos))
 
 	local wielded = digger:get_wielded_item()
-	local drops = core.get_node_drops(node.name, wielded:get_name())
+	local drops = core.get_node_drops(node, wielded:get_name())
 
 	local wdef = wielded:get_definition()
 	local tp = wielded:get_tool_capabilities()
diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index a3413221b..9bd92b34a 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -531,9 +531,11 @@ for conversion.
 If the `ItemStack`'s metadata contains the `color` field, it will be
 lost on placement, because nodes on the map can only use palettes.
 
-If the `ItemStack`'s metadata contains the `palette_index` field, you
-currently must manually convert between it and the node's `param2` with
-custom `on_place` and `on_dig` callbacks.
+If the `ItemStack`'s metadata contains the `palette_index` field, it is
+automatically transferred between node and item forms by the engine,
+when a player digs or places a colored node.
+You can disable this feature by setting the `drop` field of the node
+to itself (without metadata).
 
 ### Colored items in craft recipes
 Craft recipes only support item strings, but fortunately item strings
@@ -3326,8 +3328,9 @@ An `InvRef` is a reference to an inventory.
 * `add_item(listname, stack)`: add item somewhere in list, returns leftover `ItemStack`
 * `room_for_item(listname, stack):` returns `true` if the stack of items
   can be fully added to the list
-* `contains_item(listname, stack)`: returns `true` if the stack of items
-  can be fully taken from the list
+* `contains_item(listname, stack, [match_meta])`: returns `true` if
+  the stack of items can be fully taken from the list.
+  If `match_meta` is false, only the items' names are compared (default: `false`).
 * `remove_item(listname, stack)`: take as many items as specified from the list,
   returns the items that were actually removed (as an `ItemStack`) -- note that
   any item metadata is ignored, so attempting to remove a specific unique
diff --git a/src/game.cpp b/src/game.cpp
index 325557723..b81efc33f 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -774,8 +774,8 @@ public:
 };
 
 
-bool nodePlacementPrediction(Client &client,
-		const ItemDefinition &playeritem_def, v3s16 nodepos, v3s16 neighbourpos)
+bool nodePlacementPrediction(Client &client, const ItemDefinition &playeritem_def,
+	const ItemStack &playeritem, v3s16 nodepos, v3s16 neighbourpos)
 {
 	std::string prediction = playeritem_def.node_placement_prediction;
 	INodeDefManager *nodedef = client.ndef();
@@ -818,11 +818,13 @@ bool nodePlacementPrediction(Client &client,
 			return false;
 		}
 
+		const ContentFeatures &predicted_f = nodedef->get(id);
+
 		// Predict param2 for facedir and wallmounted nodes
 		u8 param2 = 0;
 
-		if (nodedef->get(id).param_type_2 == CPT2_WALLMOUNTED ||
-				nodedef->get(id).param_type_2 == CPT2_COLORED_WALLMOUNTED) {
+		if (predicted_f.param_type_2 == CPT2_WALLMOUNTED ||
+				predicted_f.param_type_2 == CPT2_COLORED_WALLMOUNTED) {
 			v3s16 dir = nodepos - neighbourpos;
 
 			if (abs(dir.Y) > MYMAX(abs(dir.X), abs(dir.Z))) {
@@ -834,8 +836,8 @@ bool nodePlacementPrediction(Client &client,
 			}
 		}
 
-		if (nodedef->get(id).param_type_2 == CPT2_FACEDIR ||
-				nodedef->get(id).param_type_2 == CPT2_COLORED_FACEDIR) {
+		if (predicted_f.param_type_2 == CPT2_FACEDIR ||
+				predicted_f.param_type_2 == CPT2_COLORED_FACEDIR) {
 			v3s16 dir = nodepos - floatToInt(client.getEnv().getLocalPlayer()->getPosition(), BS);
 
 			if (abs(dir.X) > abs(dir.Z)) {
@@ -848,7 +850,7 @@ bool nodePlacementPrediction(Client &client,
 		assert(param2 <= 5);
 
 		//Check attachment if node is in group attached_node
-		if (((ItemGroupList) nodedef->get(id).groups)["attached_node"] != 0) {
+		if (((ItemGroupList) predicted_f.groups)["attached_node"] != 0) {
 			static v3s16 wallmounted_dirs[8] = {
 				v3s16(0, 1, 0),
 				v3s16(0, -1, 0),
@@ -859,8 +861,8 @@ bool nodePlacementPrediction(Client &client,
 			};
 			v3s16 pp;
 
-			if (nodedef->get(id).param_type_2 == CPT2_WALLMOUNTED ||
-					nodedef->get(id).param_type_2 == CPT2_COLORED_WALLMOUNTED)
+			if (predicted_f.param_type_2 == CPT2_WALLMOUNTED ||
+					predicted_f.param_type_2 == CPT2_COLORED_WALLMOUNTED)
 				pp = p + wallmounted_dirs[param2];
 			else
 				pp = p + v3s16(0, -1, 0);
@@ -869,6 +871,28 @@ bool nodePlacementPrediction(Client &client,
 				return false;
 		}
 
+		// Apply color
+		if ((predicted_f.param_type_2 == CPT2_COLOR
+				|| predicted_f.param_type_2 == CPT2_COLORED_FACEDIR
+				|| predicted_f.param_type_2 == CPT2_COLORED_WALLMOUNTED)) {
+			const std::string &indexstr = playeritem.metadata.getString(
+				"palette_index", 0);
+			if (!indexstr.empty()) {
+				s32 index = mystoi(indexstr);
+				if (predicted_f.param_type_2 == CPT2_COLOR) {
+					param2 = index;
+				} else if (predicted_f.param_type_2
+						== CPT2_COLORED_WALLMOUNTED) {
+					// param2 = pure palette index + other
+					param2 = (index & 0xf8) | (param2 & 0x07);
+				} else if (predicted_f.param_type_2
+						== CPT2_COLORED_FACEDIR) {
+					// param2 = pure palette index + other
+					param2 = (index & 0xe0) | (param2 & 0x1f);
+				}
+			}
+		}
+
 		// Add node to client map
 		MapNode n(id, 0, param2);
 
@@ -1277,8 +1301,9 @@ protected:
 			const core::line3d<f32> &shootline, bool liquids_pointable,
 			bool look_for_object, const v3s16 &camera_offset);
 	void handlePointingAtNothing(const ItemStack &playerItem);
-	void handlePointingAtNode(const PointedThing &pointed, const ItemDefinition &playeritem_def,
-			const ToolCapabilities &playeritem_toolcap, f32 dtime);
+	void handlePointingAtNode(const PointedThing &pointed,
+		const ItemDefinition &playeritem_def, const ItemStack &playeritem,
+		const ToolCapabilities &playeritem_toolcap, f32 dtime);
 	void handlePointingAtObject(const PointedThing &pointed, const ItemStack &playeritem,
 			const v3f &player_position, bool show_debug);
 	void handleDigging(const PointedThing &pointed, const v3s16 &nodepos,
@@ -3599,7 +3624,8 @@ void Game::processPlayerInteraction(f32 dtime, bool show_hud, bool show_debug)
 		if (playeritem.name.empty() && hand_def.tool_capabilities != NULL) {
 			playeritem_toolcap = *hand_def.tool_capabilities;
 		}
-		handlePointingAtNode(pointed, playeritem_def, playeritem_toolcap, dtime);
+		handlePointingAtNode(pointed, playeritem_def, playeritem,
+			playeritem_toolcap, dtime);
 	} else if (pointed.type == POINTEDTHING_OBJECT) {
 		handlePointingAtObject(pointed, playeritem, player_position, show_debug);
 	} else if (isLeftPressed()) {
@@ -3734,8 +3760,9 @@ void Game::handlePointingAtNothing(const ItemStack &playerItem)
 }
 
 
-void Game::handlePointingAtNode(const PointedThing &pointed, const ItemDefinition &playeritem_def,
-		const ToolCapabilities &playeritem_toolcap, f32 dtime)
+void Game::handlePointingAtNode(const PointedThing &pointed,
+	const ItemDefinition &playeritem_def, const ItemStack &playeritem,
+	const ToolCapabilities &playeritem_toolcap, f32 dtime)
 {
 	v3s16 nodepos = pointed.node_undersurface;
 	v3s16 neighbourpos = pointed.node_abovesurface;
@@ -3795,7 +3822,7 @@ void Game::handlePointingAtNode(const PointedThing &pointed, const ItemDefinitio
 			// If the wielded item has node placement prediction,
 			// make that happen
 			bool placed = nodePlacementPrediction(*client,
-					playeritem_def,
+					playeritem_def, playeritem,
 					nodepos, neighbourpos);
 
 			if (placed) {
diff --git a/src/inventory.cpp b/src/inventory.cpp
index 25f524150..5ce82737a 100644
--- a/src/inventory.cpp
+++ b/src/inventory.cpp
@@ -658,7 +658,7 @@ bool InventoryList::roomForItem(const ItemStack &item_) const
 	return false;
 }
 
-bool InventoryList::containsItem(const ItemStack &item) const
+bool InventoryList::containsItem(const ItemStack &item, bool match_meta) const
 {
 	u32 count = item.count;
 	if(count == 0)
@@ -669,9 +669,9 @@ bool InventoryList::containsItem(const ItemStack &item) const
 	{
 		if(count == 0)
 			break;
-		if(i->name == item.name)
-		{
-			if(i->count >= count)
+		if (i->name == item.name
+				&& (!match_meta || (i->metadata == item.metadata))) {
+			if (i->count >= count)
 				return true;
 			else
 				count -= i->count;
diff --git a/src/inventory.h b/src/inventory.h
index e3e818708..04c8156c8 100644
--- a/src/inventory.h
+++ b/src/inventory.h
@@ -223,9 +223,10 @@ public:
 	// Checks whether there is room for a given item
 	bool roomForItem(const ItemStack &item) const;
 
-	// Checks whether the given count of the given item name
+	// Checks whether the given count of the given item
 	// exists in this inventory list.
-	bool containsItem(const ItemStack &item) const;
+	// If match_meta is false, only the items' names are compared.
+	bool containsItem(const ItemStack &item, bool match_meta) const;
 
 	// Removes the given count of the given item name from
 	// this inventory list. Walks the list in reverse order.
diff --git a/src/script/lua_api/l_inventory.cpp b/src/script/lua_api/l_inventory.cpp
index f5e76a7b6..e92197c14 100644
--- a/src/script/lua_api/l_inventory.cpp
+++ b/src/script/lua_api/l_inventory.cpp
@@ -325,8 +325,8 @@ int InvRef::l_room_for_item(lua_State *L)
 	return 1;
 }
 
-// contains_item(self, listname, itemstack or itemstring or table or nil) -> true/false
-// Returns true if the list contains the given count of the given item name
+// contains_item(self, listname, itemstack or itemstring or table or nil, [match_meta]) -> true/false
+// Returns true if the list contains the given count of the given item
 int InvRef::l_contains_item(lua_State *L)
 {
 	NO_MAP_LOCK_REQUIRED;
@@ -334,8 +334,11 @@ int InvRef::l_contains_item(lua_State *L)
 	const char *listname = luaL_checkstring(L, 2);
 	ItemStack item = read_item(L, 3, getServer(L)->idef());
 	InventoryList *list = getlist(L, ref, listname);
-	if(list){
-		lua_pushboolean(L, list->containsItem(item));
+	bool match_meta = false;
+	if (lua_isboolean(L, 4))
+		match_meta = lua_toboolean(L, 4);
+	if (list) {
+		lua_pushboolean(L, list->containsItem(item, match_meta));
 	} else {
 		lua_pushboolean(L, false);
 	}
diff --git a/src/script/lua_api/l_inventory.h b/src/script/lua_api/l_inventory.h
index 91d41c0d0..502827a11 100644
--- a/src/script/lua_api/l_inventory.h
+++ b/src/script/lua_api/l_inventory.h
@@ -93,7 +93,7 @@ private:
 	// Returns true if the item completely fits into the list
 	static int l_room_for_item(lua_State *L);
 
-	// contains_item(self, listname, itemstack or itemstring or table or nil) -> true/false
+	// contains_item(self, listname, itemstack or itemstring or table or nil, [match_meta]) -> true/false
 	// Returns true if the list contains the given count of the given item name
 	static int l_contains_item(lua_State *L);