Simple visinv tweening

- On door convey
- On item ent settling

Only able to support limited cases, and still can't
usefully animate nodes, but at least this makes
some item placement behavior look smoother.

mods/nc_api_visinv/init.lua

@@ -52,15 +52,18 @@ local function itemcheck(self)
 	local pos = obj:get_pos()
 	if not pos then visinv_ents[self] = nil return end
 
+	local rp = vector.round(pos)
+	local nodemeta = minetest.get_meta(rp)
+	local tweenfrom = minetest.deserialize(nodemeta:get_string("tweenfrom"))
+
 	local stack = nodecore.stack_get(pos)
 
 	local sstr = stack:to_string()
-	if self.stackstring == sstr then return end
+	if (not tweenfrom) and self.stackstring == sstr then return end
 	self.stackstring = sstr
 
 	if stack:is_empty() then return objremove(self, obj) end
 
-	local rp = vector.round(pos)
 	local def = minetest.registered_items[stack:get_name()] or {}
 	local src = def.light_source or 0
 	if src > 0 then
@@ -70,14 +73,24 @@ local function itemcheck(self)
 
 	local props, scale, yaw = nodecore.stackentprops(stack,
 		rp.x * 3 + rp.y * 5 + rp.z * 7)
-	rp.y = rp.y + scale - 31/64
+	local op = {
+		x = rp.x,
+		y = rp.y + scale - 31/64,
+		z = rp.z
+	}
+
+	if tweenfrom then
+		nodemeta:set_string("tweenfrom", "")
+		obj:set_pos(tweenfrom)
+		obj:move_to(op)
+	elseif not vector.equals(obj:get_pos(), op) then
+		obj:set_pos(op)
+	end
 
 	if obj:get_yaw() ~= yaw then
 		obj:set_yaw(yaw)
 	end
-	if not vector.equals(obj:get_pos(), rp) then
-		obj:set_pos(rp)
-	end
+
 	return obj:set_properties(props)
 end
 

mods/nc_doors/convey.lua

@@ -35,7 +35,10 @@ local function tryprocess(item, retry)
 			local meta = minetest.get_meta(item.from):to_table()
 			minetest.remove_node(item.from)
 			nodecore.set_loud(t, node)
+			meta.fields = meta.fields or {}
+			meta.fields.tweenfrom = minetest.serialize(item.from)
 			minetest.get_meta(t):from_table(meta)
+			nodecore.visinv_update_ents(t)
 			nodecore.fallcheck(t)
 			local re = retry[hashpos(item.from)]
 			if not re then return end

mods/nc_items/ent_item.lua

@@ -44,6 +44,8 @@ nodecore.register_item_entity_on_settle(function(self, pos)
 			and (rel.y <= 0 or (p.y - 1 < nodecore.map_limit_min)
 				or nodecore.walkable({x = p.x, y = p.y - 1, z = p.z})) then
 				nodecore.place_stack(p, item)
+				minetest.get_meta(p):set_string("tweenfrom",
+					minetest.serialize(self.object:get_pos()))
 				self.itemstring = ""
 				self.object:remove()
 				return true