Update init.lua

Improved consistency across reload using staticdata. Specifically, drops at rest on irregular node boxes are not read as entombed.
Rearranged conditionals to simplify planned behaviour extension.

init.lua

@@ -15,90 +15,104 @@ http://www.gnu.org/licenses/lgpl-2.1.html
 
 
 local function in_walkable(p)
-	local n=minetest.get_node_or_nil(p)
+	local n = minetest.get_node_or_nil(p)
 	return n and minetest.registered_nodes[n.name].walkable
 end
 
--- Update drop's physics and flags.
+
+-- Update drop physics and flags.
 local function disentomb(obj)
 	local p = obj:getpos()
 	if p then
-		local ent = obj:get_luaentity()
 
-		if in_walkable(p) then
-			local brace = math.floor(p.y) + 0.800001
-			if ent.is_entombed then
-				obj:setpos({x = p.x, y = brace + 1, z = p.z})
-				-- suppress bouncing
-				if not in_walkable(obj:getpos()) then
-					ent.is_entombed = false
-				end
-			else
+		local ent = obj:get_luaentity()
+		local w = in_walkable(p)
+		local brace = math.floor(p.y) + 0.800001
+
+		if ent.is_entombed then
+			local p2 = p
+			if w then
+				p2 = {x = p.x, y = brace + 1, z = p.z}
+				obj:setpos(p2)
+			end
+			ent.is_entombed = in_walkable(p2)
+		else
+			if w then
 				obj:setpos({x = p.x, y = brace, z = p.z})
 				ent.is_entombed = true
 			end
-
-			if ent.is_entombed then
-				minetest.after(1.0, disentomb, obj)
-			end
-		else
-			ent.is_entombed = false
 		end
+
+		if ent.is_entombed then
+			obj:setvelocity({x = 0, y = 0, z = 0})
+			obj:setacceleration({x = 0, y = 0, z = 0})
+			minetest.after(1.0, disentomb, obj)
+		end
+
 	end
 end
 
 
--- Properties set by on_activate are not accessible until it returns
--- so this function polls until they are before continuing.
+
+-- Poll until defaults are ready before continuing.
 local function wait_itemstring(ent, c)
 	if ent.itemstring == "" then
 		if c < 10 then
-			minetest.after(0.1, wait_itemstring, ent, c + 1)  -- 2 ticks
+			minetest.after(0.1, wait_itemstring, ent, c + 1)
 		end
 		return
 	end
 
-	local obj = ent.object
-	disentomb(obj)
-
-	-- stabilise entombed spawns
-	if in_walkable(obj:getpos()) then
-		obj:setvelocity({x = 0, y = 0, z = 0})
-		obj:setacceleration({x = 0,y = 0, z = 0})
+	if ent.is_entombed then
+		disentomb(ent.object)
 	end
 end
 
 
+
 local function append_to_core_defns()
 	local dropentity=minetest.registered_entities["__builtin:item"]
 
-	dropentity.is_entombed = false
-
-	-- Update drops when reloaded or spawned to maintain consistent behaviour.
+	-- Ensure consistency across reloads.
 	local on_activate_copy = dropentity.on_activate
 	dropentity.on_activate = function(ent, staticdata, dtime_s)
-		local r = {on_activate_copy(ent, staticdata, dtime_s)}
-		wait_itemstring(ent,0)
-		return unpack(r)
+		on_activate_copy(ent, staticdata, dtime_s)
+		if staticdata ~= "" then
+			ent.is_entombed = minetest.deserialize(staticdata).is_entombed
+		end
+		wait_itemstring(ent, 0)
+	end
+
+	-- Preserve state across reloads
+	local get_staticdata_copy = dropentity.get_staticdata
+	dropentity.get_staticdata = function(ent)
+		local s = get_staticdata_copy(ent)
+		if ent.is_entombed then
+			local r = {}
+			if s ~= "" then
+				r = minetest.deserialize(s)
+			end
+			r.is_entombed=true
+			return minetest.serialize(r)
+		end
+		return s
 	end
 
 	-- Update drops inside newly placed (including fallen) nodes.
 	local add_node_copy = minetest.add_node
 	minetest.add_node = function(pos,node)
-		local r = {add_node_copy(pos, node)}
-
-		local a = minetest.get_objects_inside_radius(pos, 0.87)  -- Radius must include cube corners.
+		add_node_copy(pos, node)
+		local a = minetest.get_objects_inside_radius(pos, 0.87)
 		for _,obj in ipairs(a) do
 			local ent = obj:get_luaentity()
 			if ent and ent.name == "__builtin:item" then
 				disentomb(obj)
 			end
 		end
-
-		return unpack(r)
 	end
+
 end
 
 
-append_to_core_defns()
 
+append_to_core_defns()