Implement dropped items as LuaEntities; leave the old ones as is for compatibility

builtin/builtin.lua

@@ -13,6 +13,7 @@ math.randomseed(os.time())
 dofile(minetest.get_modpath("__builtin").."/misc_helpers.lua")
 dofile(minetest.get_modpath("__builtin").."/item.lua")
 dofile(minetest.get_modpath("__builtin").."/misc_register.lua")
+dofile(minetest.get_modpath("__builtin").."/item_entity.lua")
 dofile(minetest.get_modpath("__builtin").."/deprecated.lua")
 dofile(minetest.get_modpath("__builtin").."/misc.lua")
 dofile(minetest.get_modpath("__builtin").."/privileges.lua")

builtin/item.lua

@@ -192,7 +192,17 @@ function minetest.item_place(itemstack, placer, pointed_thing)
 end
 
 function minetest.item_drop(itemstack, dropper, pos)
+	if dropper.get_player_name then
+		local v = dropper:get_look_dir()
+		local p = {x=pos.x+v.x, y=pos.y+1.5+v.y, z=pos.z+v.z}
+		local obj = minetest.env:add_item(p, itemstack)
+		v.x = v.x*2
+		v.y = v.y*2 + 1
+		v.z = v.z*2
+		obj:setvelocity(v)
+	else
 		minetest.env:add_item(pos, itemstack)
+	end
 	return ""
 end
 
@@ -377,4 +387,3 @@ minetest.noneitemdef_default = {  -- This is used for the hand and unknown items
 	on_use = nil,
 }
 
-

builtin/item_entity.lua

@@ -0,0 +1,90 @@
+-- Minetest: builtin/item_entity.lua
+
+function minetest.spawn_item(pos, item)
+	-- Take item in any format
+	local stack = ItemStack(item)
+	local obj = minetest.env:add_entity(pos, "__builtin:item")
+	obj:get_luaentity():set_item(stack:to_string())
+	return obj
+end
+
+minetest.register_entity("__builtin:item", {
+	initial_properties = {
+		hp_max = 1,
+		physical = true,
+		collisionbox = {-0.25,-0.25,-0.25, 0.25,0.25,0.25},
+		visual = "sprite",
+		visual_size = {x=0.5, y=0.5},
+		textures = {""},
+		spritediv = {x=1, y=1},
+		initial_sprite_basepos = {x=0, y=0},
+		is_visible = false,
+	},
+	
+	itemstring = '',
+	physical_state = true,
+
+	set_item = function(self, itemstring)
+		self.itemstring = itemstring
+		local stack = ItemStack(itemstring)
+		local itemtable = stack:to_table()
+		local itemname = nil
+		if itemtable then
+			itemname = stack:to_table().name
+		end
+		local item_texture = nil
+		if minetest.registered_items[itemname] then
+			item_texture = minetest.registered_items[itemname].inventory_image
+		end
+		item_texture = item_texture or "unknown_item.png"
+		self.object:set_properties({
+			textures = {item_texture},
+			is_visible = true,
+		})
+	end,
+
+	get_staticdata = function(self)
+		return self.itemstring
+	end,
+
+	on_activate = function(self, staticdata)
+		self.itemstring = staticdata
+		self.object:set_armor_groups({immortal=1})
+		self.object:setvelocity({x=0, y=2, z=0})
+		self.object:setacceleration({x=0, y=-10, z=0})
+		self:set_item(self.itemstring)
+	end,
+
+	on_step = function(self, dtime)
+		local p = self.object:getpos()
+		p.y = p.y - 0.3
+		local nn = minetest.env:get_node(p).name
+		if minetest.registered_nodes[nn].walkable then
+			if self.physical_state then
+				self.object:setvelocity({x=0,y=0,z=0})
+				self.object:setacceleration({x=0, y=0, z=0})
+				self.physical_state = false
+				self.object:set_properties({
+					physical = false
+				})
+			end
+		else
+			if not self.physical_state then
+				self.object:setvelocity({x=0,y=0,z=0})
+				self.object:setacceleration({x=0, y=-10, z=0})
+				self.physical_state = true
+				self.object:set_properties({
+					physical = true
+				})
+			end
+		end
+	end,
+
+	on_punch = function(self, hitter)
+		if self.itemstring ~= '' then
+			hitter:get_inventory():add_item("main", self.itemstring)
+		end
+		self.object:remove()
+	end,
+})
+

doc/lua_api.txt

@@ -637,15 +637,18 @@ methods:
   ^ Returns nil for unloaded area
 - get_node_light(pos, timeofday) -> 0...15 or nil
   ^ timeofday: nil = current time, 0 = night, 0.5 = day
-- add_entity(pos, name): Returns ObjectRef or nil if failed
-- add_item(pos, itemstring)
-- add_rat(pos)
-- add_firefly(pos)
+- add_entity(pos, name): Spawn Lua-defined entity at position
+  ^ Returns ObjectRef, or nil if failed
+- add_item(pos, itemstring): Spawn item
+  ^ Returns ObjectRef, or nil if failed
 - get_meta(pos) -- Get a NodeMetaRef at that position
 - get_player_by_name(name) -- Get an ObjectRef to a player
 - get_objects_inside_radius(pos, radius)
 - set_timeofday(val): val: 0...1; 0 = midnight, 0.5 = midday
 - get_timeofday()
+Deprecated:
+- add_rat(pos): Add C++ rat object (no-op)
+- add_firefly(pos): Add C++ firefly object (no-op)
 
 NodeMetaRef (this stuff is subject to change in a future version)
 methods:

src/content_cao.cpp

@@ -1069,6 +1069,11 @@ public:
 			bool is_end_position = readU8(is);
 			float update_interval = readF1000(is);
 
+			// Place us a bit higher if we're physical, to not sink into
+			// the ground due to sucky collision detection...
+			if(m_prop.physical)
+				m_position += v3f(0,0.002,0);
+			
 			if(do_interpolate){
 				if(!m_prop.physical)
 					pos_translator.update(m_position, is_end_position, update_interval);

src/scriptapi.cpp

@@ -3042,7 +3042,21 @@ private:
 		ItemStack item = read_item(L, 3);
 		if(item.empty() || !item.isKnown(get_server(L)->idef()))
 			return 0;
-		// Do it
+		// Use minetest.spawn_item to spawn a __builtin:item
+		lua_getglobal(L, "minetest");
+		lua_getfield(L, -1, "spawn_item");
+		if(lua_isnil(L, -1))
+			return 0;
+		lua_pushvalue(L, 2);
+		lua_pushstring(L, item.getItemString().c_str());
+		if(lua_pcall(L, 2, 1, 0))
+			script_error(L, "error: %s", lua_tostring(L, -1));
+		return 1;
+		/*lua_pushvalue(L, 1);
+		lua_pushstring(L, "__builtin:item");
+		lua_pushstring(L, item.getItemString().c_str());
+		return l_add_entity(L);*/
+		/*// Do it
 		ServerActiveObject *obj = createItemSAO(env, pos, item.getItemString());
 		int objectid = env->addActiveObject(obj);
 		// If failed to add, return nothing (reads as nil)
@@ -3050,7 +3064,7 @@ private:
 			return 0;
 		// Return ObjectRef
 		objectref_get_or_create(L, obj);
-		return 1;
+		return 1;*/
 	}
 
 	// EnvRef:add_rat(pos)