Merge pull request #1 from FaceDeer/layout-refactor

Layout refactor

class_layout.lua

@@ -1,27 +1,56 @@
-digtron.get_all_digtron_neighbours = function(pos, player)
+DigtronLayout = {}
-	-- returns table containing a list of all digtron node locations, lists of special digtron node types, a table of the coordinate extents of the digtron array, a Pointset of protected nodes, and a number to determine how many adjacent solid non-digtron nodes there are (for traction)
+DigtronLayout.__index = DigtronLayout
+
+-------------------------------------------------------------------------
+-- Creation
+
+local get_node_image = function(pos, node)
+	local node_image = {node=node, pos={x=pos.x, y=pos.y, z=pos.z}}
+	node_image.paramtype2 = minetest.registered_nodes[node.name].paramtype2
+	local meta = minetest.get_meta(pos)
+	node_image.meta = meta:to_table()
+	
+	-- Record what kind of thing we've got in a builder node so its facing can be rotated properly
+	if minetest.get_item_group(node.name, "digtron") == 4 then
+		local build_item = node_image.meta.inventory.main[1]
+		if build_item ~= "" then
+			local build_item_def = minetest.registered_nodes[ItemStack(build_item):get_name()]
+			if build_item_def ~= nil then
+				node_image.build_item_paramtype2 = build_item_def.paramtype2
+			end
+		end
+	end
+	return node_image
+end
+
+function DigtronLayout.create(pos, player)
+	local self = {}
+	setmetatable(self,DigtronLayout)
 
-	local layout = {}
 	--initialize. We're assuming that the start position is a controller digtron, should be a safe assumption since only the controller node should call this
-	layout.traction = 0
+	self.traction = 0
-	layout.all = {}
+	self.all = {}
-	layout.inventories = {}
+	self.inventories = {}
-	layout.fuelstores = {}
+	self.fuelstores = {}
-	layout.diggers = {}
+	self.diggers = {}
-	layout.builders = {}
+	self.builders = {}
-	layout.extents = {}
+	self.extents = {}
-	layout.water_touching = false
+	self.water_touching = false
-	layout.lava_touching = false
+	self.lava_touching = false
-	layout.protected = Pointset.create() -- if any nodes we look at are protected, make note of that. That way we don't need to keep re-testing protection state later.
+	self.protected = Pointset.create() -- if any nodes we look at are protected, make note of that. That way we don't need to keep re-testing protection state later.
-	layout.controller = {x=pos.x, y=pos.y, z=pos.z} 	--Make a deep copy of the pos parameter just in case the calling code wants to play silly buggers with it
+	self.old_pos_pointset = Pointset.create() -- For tracking original location of nodes if we do transformations on the Digtron
+	self.nodes_dug = Pointset.create() -- For tracking adjacent nodes that will have been dug by digger heads in future
+	self.contains_protected_node = false -- used to indicate if at least one node in this digtron array is protected from the player.
+	self.controller = {x=pos.x, y=pos.y, z=pos.z} 	--Make a deep copy of the pos parameter just in case the calling code wants to play silly buggers with it
 
-	table.insert(layout.all, layout.controller)
+	table.insert(self.all, get_node_image(pos, minetest.get_node(pos))) -- We never visit the source node, so insert it into the all table a priori. Revisit this if a controller node is created that contains fuel or inventory or whatever.
-	layout.extents.max_x = pos.x
+
-	layout.extents.min_x = pos.x
+	self.extents.max_x = pos.x
-	layout.extents.max_y = pos.y
+	self.extents.min_x = pos.x
-	layout.extents.min_y = pos.y
+	self.extents.max_y = pos.y
-	layout.extents.max_z = pos.z
+	self.extents.min_y = pos.y
-	layout.extents.min_z = pos.z
+	self.extents.max_z = pos.z
+	self.extents.min_z = pos.z
 	
 	-- temporary pointsets used while searching
 	local to_test = Pointset.create()
@@ -36,7 +65,8 @@ digtron.get_all_digtron_neighbours = function(pos, player)
 	to_test:set(pos.x, pos.y, pos.z - 1, true)
 	
 	if minetest.is_protected(pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
-		layout.protected:set(pos.x, pos.y, pos.z, true)
+		self.protected:set(pos.x, pos.y, pos.z, true)
+		self.contains_protected_node = true
 	end
 	
 	-- Do a loop on to_test positions, adding new to_test positions as we find digtron nodes. This is a flood fill operation
@@ -48,50 +78,51 @@ digtron.get_all_digtron_neighbours = function(pos, player)
 
 		if node.name == "ignore" then
 			--buildtron array is next to unloaded nodes, too dangerous to do anything. Abort.
-			layout.all = nil
+			return nil
-			return layout
-		end
-
-		if minetest.is_protected(pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
-			layout.protected:set(testpos.x, testpos.y, testpos.z, true)
 		end
 		
 		if minetest.get_item_group(node.name, "water") ~= 0 then
-			layout.water_touching = true
+			self.water_touching = true
 		elseif minetest.get_item_group(node.name, "lava") ~= 0 then
-			layout.lava_touching = true
+			self.lava_touching = true
 			if digtron.lava_impassible == true then
-				layout.protected:set(testpos.x, testpos.y, testpos.z, true)
+				self.protected:set(testpos.x, testpos.y, testpos.z, true)
 			end
 		end
 		
 		local group_number = minetest.get_item_group(node.name, "digtron")
 		if group_number > 0 then
 			--found one. Add it to the digtrons output
-			table.insert(layout.all, testpos)
+			local node_image = get_node_image(testpos, node)
 			
-			-- update extents
+			table.insert(self.all, node_image)
-			layout.extents.max_x = math.max(layout.extents.max_x, testpos.x)
-			layout.extents.min_x = math.min(layout.extents.min_x, testpos.x)
-			layout.extents.max_y = math.max(layout.extents.max_y, testpos.y)
-			layout.extents.min_y = math.min(layout.extents.min_y, testpos.y)
-			layout.extents.max_z = math.max(layout.extents.max_z, testpos.z)
-			layout.extents.min_z = math.min(layout.extents.min_z, testpos.z)
 
 			-- add a reference to this node's position to special node lists
 			if group_number == 2 then
-				table.insert(layout.inventories, testpos)
+				table.insert(self.inventories, node_image)
 			elseif group_number == 3 then
-				table.insert(layout.diggers, testpos)
+				table.insert(self.diggers, node_image)
 			elseif group_number == 4 then
-				table.insert(layout.builders, testpos)
+				table.insert(self.builders, node_image)
 			elseif group_number == 5 then
-				table.insert(layout.fuelstores, testpos)
+				table.insert(self.fuelstores, node_image)
 			elseif group_number == 6 then
-				table.insert(layout.inventories, testpos)
+				table.insert(self.inventories, node_image)
-				table.insert(layout.fuelstores, testpos)
+				table.insert(self.fuelstores, node_image)
 			end
 			
+			if minetest.is_protected(pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
+				self.contains_protected_node = true
+			end
+			
+			-- update extents
+			self.extents.max_x = math.max(self.extents.max_x, testpos.x)
+			self.extents.min_x = math.min(self.extents.min_x, testpos.x)
+			self.extents.max_y = math.max(self.extents.max_y, testpos.y)
+			self.extents.min_y = math.min(self.extents.min_y, testpos.y)
+			self.extents.max_z = math.max(self.extents.max_z, testpos.z)
+			self.extents.min_z = math.min(self.extents.min_z, testpos.z)
+			
 			--queue up potential new test points adjacent to this digtron node
 			to_test:set_if_not_in(tested, testpos.x + 1, testpos.y, testpos.z, true)
 			to_test:set_if_not_in(tested, testpos.x - 1, testpos.y, testpos.z, true)
@@ -101,17 +132,17 @@ digtron.get_all_digtron_neighbours = function(pos, player)
 			to_test:set_if_not_in(tested, testpos.x, testpos.y, testpos.z - 1, true)
 		elseif minetest.registered_nodes[node.name].buildable_to ~= true then
 			-- Tracks whether the digtron is hovering in mid-air. If any part of the digtron array touches something solid it gains traction.
-			layout.traction = layout.traction + 1
+			self.traction = self.traction + 1
 		end
 		
 		testpos, _ = to_test:pop()
 	end
 			
-	return layout
+	return self
 end
 
--- Rotation magic
+------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------
+-- Rotation
 
 local facedir_rotate = {
 	['x'] = {
@@ -171,23 +202,6 @@ local rotate_pos = function(axis, direction, pos)
 	end
 end
 
-local get_node_image = function(pos, node)
-	local node_image = {node=node, pos={x=pos.x, y=pos.y, z=pos.z}}
-	node_image.paramtype2 = minetest.registered_nodes[node.name].paramtype2
-	local meta = minetest.get_meta(pos)
-	node_image.meta = meta:to_table()
-	
-	-- Record what kind of thing we've got in a builder node so its facing can be rotated properly
-	if minetest.get_item_group(node.name, "digtron") == 4 then
-		local build_item = node_image.meta.inventory.main[1]
-		if build_item ~= "" then
-			local build_item_def = minetest.registered_nodes[ItemStack(build_item):get_name()]
-			node_image.build_item_paramtype2 = build_item_def.paramtype2
-		end
-	end
-	return node_image
-end
-
 local rotate_node_image = function(node_image, origin, axis, direction, old_pos_pointset)
 	-- Facings
 	if node_image.paramtype2 == "wallmounted" then
@@ -216,7 +230,8 @@ local rotate_node_image = function(node_image, origin, axis, direction, old_pos_
 	return node_image	
 end
 
-digtron.rotate_layout_image = function(layout_image, facedir)
+-- Rotates 90 degrees widdershins around the axis defined by facedir (which in this case is pointing out the front of the node, so it needs to be converted into an upward-pointing axis internally)
+function DigtronLayout.rotate_layout_image(self, facedir)
 	-- To convert this into the direction the "top" of the axel node is pointing in:
 	-- 0, 1, 2, 3 == (0,1,0)
 	-- 4, 5, 6, 7 == (0,0,1)
@@ -235,40 +250,91 @@ digtron.rotate_layout_image = function(layout_image, facedir)
 	}
 	local params = top[math.floor(facedir/4)]
 	
-	layout_image.old_pos_pointset = Pointset:create()
+	for k, node_image in pairs(self.all) do
-	
+		rotate_node_image(node_image, self.controller, params.axis, params.dir, self.old_pos_pointset)
-	for k, node_image in pairs(layout_image.all) do
-		rotate_node_image(node_image, layout_image.controller, params.axis, params.dir, layout_image.old_pos_pointset)
 	end
-	return layout_image
+	return self
 end
 
-digtron.can_write_layout_image = function(layout_image, player)
+-----------------------------------------------------------------------------------------------
-	for k, node_image in pairs(layout_image.all) do
+-- Translation
-		if not layout_image.old_pos_pointset:get(node_image.pos.x, node_image.pos.y, node_image.pos.z)
+
+function DigtronLayout.move_layout_image(self, facing, player_name)
+	local extents = self.extents
+	local dir = digtron.facedir_to_dir_map[facing]
+	local increment
+	local filter
+	if dir == 1 then -- z+
+		filter = "z"
+		increment = 1
+		extents.max_z = extents.max_z + 1
+		extents.min_z = extents.min_z + 1
+	elseif dir == 2 then -- x+
+		filter = "x"
+		increment = 1
+		extents.max_x = extents.max_x + 1
+		extents.min_x = extents.min_x + 1
+	elseif dir == 3 then -- z-
+		filter = "z"
+		increment = -1
+		extents.max_z = extents.max_z - 1
+		extents.min_z = extents.min_z - 1
+	elseif dir == 4 then -- x-
+		filter = "x"
+		increment = -1
+		extents.max_x = extents.max_x - 1
+		extents.min_x = extents.min_x - 1
+	elseif dir == 5 then -- y-
+		filter = "y"
+		increment = -1
+		extents.max_y = extents.max_y - 1
+		extents.min_y = extents.min_y - 1
+	elseif dir == 6 then -- y+
+		filter = "y"
+		increment = 1
+		extents.max_y = extents.max_y + 1
+		extents.min_y = extents.min_y + 1
+	end
+
+	for k, node_image in pairs(self.all) do
+		self.old_pos_pointset:set(node_image.pos.x, node_image.pos.y, node_image.pos.z, true)
+		node_image.pos[filter] = node_image.pos[filter] + increment
+		self.nodes_dug:set(node_image.pos.x, node_image.pos.y, node_image.pos.z, false) -- we've moved a digtron node into this space, mark it so that we don't dig it.
+		-- TODO: log
+	end
+end
+
+-----------------------------------------------------------------------------------------------
+-- Writing to world
+
+function DigtronLayout.can_write_layout_image(self)
+	for k, node_image in pairs(self.all) do
+		-- check if the target node is buildable_to or is marked as part of the digtron that's moving
+		if not self.old_pos_pointset:get(node_image.pos.x, node_image.pos.y, node_image.pos.z)
 			and not minetest.registered_nodes[minetest.get_node(node_image.pos).name].buildable_to then
 			return false
-		elseif minetest.is_protected(node_image.pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
+		--check if we're moving into a protected node
+		elseif self.protected:get(node_image.pos) then
 			return false
 		end
 	end
 	return true
 end
 
-digtron.write_layout_image = function(layout_image)
+function DigtronLayout.write_layout_image(self)
 	-- destroy the old digtron
-	local oldpos, _ = layout_image.old_pos_pointset:pop()
+	local oldpos, _ = self.old_pos_pointset:pop()
 	while oldpos ~= nil do
 		local old_def = minetest.registered_nodes[minetest.get_node(oldpos).name]
 		minetest.remove_node(oldpos)		
 		if old_def.after_dig_node ~= nil then
 			old_def.after_dig_node(oldpos)
 		end
-		oldpos, _ = layout_image.old_pos_pointset:pop()
+		oldpos, _ = self.old_pos_pointset:pop()
 	end		
 
 	-- create the new one
-	for k, node_image in pairs(layout_image.all) do
+	for k, node_image in pairs(self.all) do
 		minetest.add_node(node_image.pos, node_image.node)
 		minetest.get_meta(node_image.pos):from_table(node_image.meta)	
 
@@ -279,81 +345,3 @@ digtron.write_layout_image = function(layout_image)
 	end
 end
 
--- Similar to get_layout, but far more comprehensive. This produces a data structure plus a set of temporary inventories that will allow the digtron to be rotated and then recreated.
-digtron.get_layout_image = function(pos, player)
-
-	local image = {}
-	--initialize. We're assuming that the start position is a controller digtron, should be a safe assumption since only the controller node should call this
-	image.all = {}
-	image.extents = {}
-	image.controller = {x=pos.x, y=pos.y, z=pos.z} 	--Make a deep copy of the pos parameter just in case the calling code wants to play silly buggers with it
-	image.contains_protected_node = false -- used to indicate if at least one node in this digtron array is protected from the player.
-	
-	table.insert(image.all, get_node_image(pos, minetest.get_node(pos)))
-
-	image.extents.max_x = pos.x
-	image.extents.min_x = pos.x
-	image.extents.max_y = pos.y
-	image.extents.min_y = pos.y
-	image.extents.max_z = pos.z
-	image.extents.min_z = pos.z
-	
-	-- temporary pointsets used while searching
-	local to_test = Pointset.create()
-	local tested = Pointset.create()
-
-	tested:set(pos.x, pos.y, pos.z, true)
-	to_test:set(pos.x + 1, pos.y, pos.z, true)
-	to_test:set(pos.x - 1, pos.y, pos.z, true)
-	to_test:set(pos.x, pos.y + 1, pos.z, true)
-	to_test:set(pos.x, pos.y - 1, pos.z, true)
-	to_test:set(pos.x, pos.y, pos.z + 1, true)
-	to_test:set(pos.x, pos.y, pos.z - 1, true)
-	
-	if minetest.is_protected(pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
-		image.contains_protected_node = true
-	end
-	
-	-- Do a loop on to_test positions, adding new to_test positions as we find digtron nodes. This is a flood fill operation
-	-- that follows node faces (no diagonals)
-	local testpos, _ = to_test:pop()
-	while testpos ~= nil do
-		tested:set(testpos.x, testpos.y, testpos.z, true) -- track nodes we've looked at to prevent infinite loops
-		local node = minetest.get_node(testpos)
-
-		if node.name == "ignore" then
-			--buildtron array is next to unloaded nodes, too dangerous to do anything. Abort.
-			return nil
-		end
-		
-		local group_number = minetest.get_item_group(node.name, "digtron")
-		if group_number > 0 then
-			--found one. Add it to the digtrons output
-			table.insert(image.all, get_node_image(testpos, node))
-
-			if minetest.is_protected(pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
-				image.contains_protected_node = true
-			end
-			
-			-- update extents
-			image.extents.max_x = math.max(image.extents.max_x, testpos.x)
-			image.extents.min_x = math.min(image.extents.min_x, testpos.x)
-			image.extents.max_y = math.max(image.extents.max_y, testpos.y)
-			image.extents.min_y = math.min(image.extents.min_y, testpos.y)
-			image.extents.max_z = math.max(image.extents.max_z, testpos.z)
-			image.extents.min_z = math.min(image.extents.min_z, testpos.z)
-			
-			--queue up potential new test points adjacent to this digtron node
-			to_test:set_if_not_in(tested, testpos.x + 1, testpos.y, testpos.z, true)
-			to_test:set_if_not_in(tested, testpos.x - 1, testpos.y, testpos.z, true)
-			to_test:set_if_not_in(tested, testpos.x, testpos.y + 1, testpos.z, true)
-			to_test:set_if_not_in(tested, testpos.x, testpos.y - 1, testpos.z, true)
-			to_test:set_if_not_in(tested, testpos.x, testpos.y, testpos.z + 1, true)
-			to_test:set_if_not_in(tested, testpos.x, testpos.y, testpos.z - 1, true)
-		end
-		
-		testpos, _ = to_test:pop()
-	end
-			
-	return image
-end

init.lua

@@ -1,5 +1,6 @@
 dofile( minetest.get_modpath( "digtron" ) .. "/util.lua" )
-dofile( minetest.get_modpath( "digtron" ) .. "/pointset.lua" )
+dofile( minetest.get_modpath( "digtron" ) .. "/class_pointset.lua" )
+dofile( minetest.get_modpath( "digtron" ) .. "/class_layout.lua" )
 dofile( minetest.get_modpath( "digtron" ) .. "/entities.lua" )
 dofile( minetest.get_modpath( "digtron" ) .. "/node_misc.lua" ) -- contains structure and light nodes
 dofile( minetest.get_modpath( "digtron" ) .. "/node_storage.lua" ) -- contains inventory and fuel storage nodes

node_axle.lua

@@ -36,10 +36,10 @@ minetest.register_node("digtron:axle", {
 			-- Been too soon since last time the digtron rotated.
 			return
 		end
-		local image = digtron.get_layout_image(pos, clicker)
+		local image = DigtronLayout.create(pos, clicker)
-		digtron.rotate_layout_image(image, node.param2)
+		image:rotate_layout_image(node.param2)
-		if digtron.can_write_layout_image(image, clicker) then
+		if image:can_write_layout_image() then
-			digtron.write_layout_image(image)
+			image:write_layout_image()
 			
 			minetest.sound_play("whirr", {gain=1.0, pos=pos})
 			meta = minetest.get_meta(pos)

node_controllers.lua

@@ -223,6 +223,7 @@ minetest.register_node("digtron:pusher", {
 		end
 
 		local newpos, status_text, return_code = digtron.execute_move_cycle(pos, clicker)
+		meta = minetest.get_meta(newpos)
 		meta:set_string("infotext", status_text)
 		
 		-- Start the delay before digtron can run again.

util.lua

@@ -3,8 +3,6 @@
 digtron = {}
 
 dofile( minetest.get_modpath( "digtron" ) .. "/util_item_place_node.lua" ) -- separated out to avoid potential for license complexity
-dofile( minetest.get_modpath( "digtron" ) .. "/util_movement.lua" ) -- separated out simply for tidiness, there's some big code in there
-dofile( minetest.get_modpath( "digtron" ) .. "/util_layout.lua" ) -- separated out simply for tidiness, there's some big code in there
 dofile( minetest.get_modpath( "digtron" ) .. "/util_execute_cycle.lua" ) -- separated out simply for tidiness, there's some big code in there
 
 -- Apparently node_sound_metal_defaults is a newer thing, I ran into games using an older version of the default mod without it.
@@ -103,7 +101,7 @@ digtron.place_in_inventory = function(itemname, inventory_positions, fallback_po
 	--tries placing the item in each inventory node in turn. If there's no room, drop it at fallback_pos
 	local itemstack = ItemStack(itemname)
 	for k, location in pairs(inventory_positions) do
-		local inv = minetest.get_inventory({type="node", pos=location})
+		local inv = minetest.get_inventory({type="node", pos=location.pos})
 		itemstack = inv:add_item("main", itemstack)
 		if itemstack:is_empty() then
 			return nil
@@ -131,10 +129,10 @@ digtron.take_from_inventory = function(itemname, inventory_positions)
 	--tries to take an item from each inventory node in turn. Returns location of inventory item was taken from on success, nil on failure
 	local itemstack = ItemStack(itemname)
 	for k, location in pairs(inventory_positions) do
-		local inv = minetest.get_inventory({type="node", pos=location})
+		local inv = minetest.get_inventory({type="node", pos=location.pos})
 		local output = inv:remove_item("main", itemstack)
 		if not output:is_empty() then
-			return location
+			return location.pos
 		end
 	end
 	return nil
@@ -162,7 +160,7 @@ digtron.burn = function(fuelstore_positions, target, test)
 		if current_burned > target then
 			break
 		end
-		local inv = minetest.get_inventory({type="node", pos=location})
+		local inv = minetest.get_inventory({type="node", pos=location.pos})
 		local invlist = inv:get_list("fuel")
 		for i, itemstack in pairs(invlist) do
 			local fuel_per_item = minetest.get_craft_result({method="fuel", width=1, items={itemstack:peek_item(1)}}).time

util_execute_cycle.lua

@@ -90,7 +90,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	local fuel_burning = meta:get_float("fuel_burning") -- get amount of burned fuel left over from last cycle
 	local status_text = string.format("Heat remaining in controller furnace: %d", fuel_burning)
 	
-	local layout = digtron.get_all_digtron_neighbours(pos, clicker)
+	local layout = DigtronLayout.create(pos, clicker)
 
 	local status_text, return_code = neighbour_test(layout, status_text)
 	if return_code ~= 0 then
@@ -103,7 +103,6 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	
 	----------------------------------------------------------------------------------------------------------------------
 	
-	local nodes_dug = Pointset.create()
 	local items_dropped = {}
 	local digging_fuel_cost = 0
 	local particle_systems = {}
@@ -113,16 +112,16 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	-- but doesn't actually dig the nodes yet. That comes later.
 	-- If we dug them now, sand would fall and some digtron nodes would die.
 	for k, location in pairs(layout.diggers) do
-		local target = minetest.get_node(location)
+		local target = minetest.get_node(location.pos)
 		local targetdef = minetest.registered_nodes[target.name]
 		if targetdef.execute_dig ~= nil then
-			local fuel_cost, dropped = targetdef.execute_dig(location, layout.protected, nodes_dug, controlling_coordinate)
+			local fuel_cost, dropped = targetdef.execute_dig(location.pos, layout.protected, layout.nodes_dug, controlling_coordinate)
 			if dropped ~= nil then
 				for _, itemname in pairs(dropped) do
 					table.insert(items_dropped, itemname)
 				end
 				if digtron.particle_effects then
-					table.insert(particle_systems, dig_dust(vector.add(location, move_dir), target.param2))
+					table.insert(particle_systems, dig_dust(vector.add(location.pos, move_dir), target.param2))
 				end
 			end
 			digging_fuel_cost = digging_fuel_cost + fuel_cost
@@ -137,8 +136,8 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	-- as having been dug.
 	local can_move = true
 	for _, location in pairs(layout.all) do
-		local newpos = digtron.find_new_pos(location, facing)
+		local newpos = digtron.find_new_pos(location.pos, facing)
-		if not digtron.can_move_to(newpos, layout.protected, nodes_dug) then
+		if not digtron.can_move_to(newpos, layout.protected, layout.nodes_dug) then
 			can_move = false
 		end
 	end
@@ -165,11 +164,11 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	local test_fuel_items = {}
 	local test_build_fuel_cost = 0		
 	for k, location in pairs(layout.builders) do
-		local target = minetest.get_node(location)
+		local target = minetest.get_node(location.pos)
 		local targetdef = minetest.registered_nodes[target.name]
-		local test_location = digtron.find_new_pos(location, facing)
+		local test_location = digtron.find_new_pos(location.pos, facing)
 		if targetdef.test_build ~= nil then
-			test_build_return_code, test_build_return_item = targetdef.test_build(location, test_location, layout.inventories, layout.protected, nodes_dug, controlling_coordinate, layout.controller)
+			test_build_return_code, test_build_return_item = targetdef.test_build(location.pos, test_location, layout.inventories, layout.protected, layout.nodes_dug, controlling_coordinate, layout.controller)
 			if test_build_return_code > 1 then
 				can_build = false
 				break
@@ -222,27 +221,23 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	-- All tests passed, ready to go for real!
 	minetest.sound_play("construction", {gain=1.0, pos=pos})
 
-	-- store or drop the products of the digger heads
-	for _, itemname in pairs(items_dropped) do
-		digtron.place_in_inventory(itemname, layout.inventories, pos)
-	end
-
 	-- if the player is standing within the array or next to it, move him too.
 	local move_player = move_player_test(layout, clicker)
 	
 	-- damage the weak flesh
 	if digtron.diggers_damage_creatures then
 		for k, location in pairs(layout.diggers) do
-			local target = minetest.get_node(location)
+			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.damage_creatures ~= nil then
-				targetdef.damage_creatures(clicker, location, digtron.find_new_pos(location, target.param2), controlling_coordinate)
+				targetdef.damage_creatures(clicker, location.pos, digtron.find_new_pos(location.pos, target.param2), controlling_coordinate)
 			end
 		end
 	end
 	
 	--move the array
-	digtron.move_digtron(facing, layout.all, layout.extents, nodes_dug, clicker:get_player_name())
+	layout:move_layout_image(facing, clicker:get_player_name())
+	layout:write_layout_image()
 	local oldpos = {x=pos.x, y=pos.y, z=pos.z}
 	pos = digtron.find_new_pos(pos, facing)
 	meta = minetest.get_meta(pos)
@@ -250,15 +245,21 @@ digtron.execute_dig_cycle = function(pos, clicker)
 		clicker:moveto(digtron.find_new_pos(clicker:getpos(), facing), true)
 	end
 	
+	-- store or drop the products of the digger heads
+	for _, itemname in pairs(items_dropped) do
+		minetest.debug("placing in inventory", itemname)
+		digtron.place_in_inventory(itemname, layout.inventories, oldpos)
+	end
+	
 	local building_fuel_cost = 0
 	local strange_failure = false
 	-- execute_build on all digtron components that have one
 	for k, location in pairs(layout.builders) do
-		local target = minetest.get_node(location)
+		local target = minetest.get_node(location.pos)
 		local targetdef = minetest.registered_nodes[target.name]
 		if targetdef.execute_build ~= nil then
 			--using the old location of the controller as fallback so that any leftovers land with the rest of the digger output. Not that there should be any.
-			local build_return = targetdef.execute_build(location, clicker, layout.inventories, layout.protected, nodes_dug, controlling_coordinate, oldpos)
+			local build_return = targetdef.execute_build(location.pos, clicker, layout.inventories, layout.protected, layout.nodes_dug, controlling_coordinate, oldpos)
 			if build_return == false then
 				-- This happens if there's insufficient inventory, but we should have confirmed there was sufficient inventory during test phase.
 				-- So this should never happen. However, "should never happens" happen sometimes. So
@@ -299,7 +300,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	
 	-- finally, dig out any nodes remaining to be dug. Some of these will have had their flag revoked because
 	-- a builder put something there or because they're another digtron node.
-	local node_to_dig, whether_to_dig = nodes_dug:pop()
+	local node_to_dig, whether_to_dig = layout.nodes_dug:pop()
 	while node_to_dig ~= nil do
 		if whether_to_dig == true then
 			minetest.log("action", string.format("%s uses Digtron to dig %s at (%d, %d, %d)", clicker:get_player_name(), minetest.get_node(node_to_dig).name, node_to_dig.x, node_to_dig.y, node_to_dig.z))
@@ -308,7 +309,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 		-- all of the digtron's nodes wind up in nodes_dug, so this is an ideal place to stick
 		-- a check to make sand fall after the digtron has passed.
 		minetest.check_for_falling({x=node_to_dig.x, y=node_to_dig.y+1, z=node_to_dig.z})
-		node_to_dig, whether_to_dig = nodes_dug:pop()
+		node_to_dig, whether_to_dig = layout.nodes_dug:pop()
 	end
 	return pos, status_text, 0
 end
@@ -317,7 +318,7 @@ end
 -- Simplified version of the above method that only moves, and doesn't execute diggers or builders.
 digtron.execute_move_cycle = function(pos, clicker)
 	local meta = minetest.get_meta(pos)
-	local layout = digtron.get_all_digtron_neighbours(pos, clicker)
+	local layout = DigtronLayout.create(pos, clicker)
 
 	local status_text = ""
 	local status_text, return_code = neighbour_test(layout, status_text)
@@ -328,17 +329,12 @@ digtron.execute_move_cycle = function(pos, clicker)
 	local facing = minetest.get_node(pos).param2
 	local controlling_coordinate = digtron.get_controlling_coordinate(pos, facing)
 
-	local nodes_dug = Pointset.create() -- empty set, we're not digging anything
+	-- if the player is standing within the array or next to it, move him too.
+	local move_player = move_player_test(layout, clicker)
 	
-	-- test if any digtrons are obstructed by non-digtron nodes that haven't been marked
+	-- test if any digtrons are obstructed by non-digtron nodes
-	-- as having been dug.
+	layout:move_layout_image(facing, clicker:get_player_name())
-	local can_move = true
+	local can_move = layout:can_write_layout_image(clicker)
-	for _, location in pairs(layout.all) do
-		local newpos = digtron.find_new_pos(location, facing)
-		if not digtron.can_move_to(newpos, layout.protected, nodes_dug) then
-			can_move = false
-		end
-	end
 	
 	if not can_move then
 		-- mark this node as waiting, will clear this flag in digtron.cycle_time seconds
@@ -351,16 +347,11 @@ digtron.execute_move_cycle = function(pos, clicker)
 
 	minetest.sound_play("truck", {gain=1.0, pos=pos})
 		
-	-- if the player is standing within the array or next to it, move him too.
-	local move_player = move_player_test(layout, clicker)
-		
 	--move the array
-	digtron.move_digtron(facing, layout.all, layout.extents, nodes_dug)
+	layout:write_layout_image()
-	local oldpos = {x=pos.x, y=pos.y, z=pos.z}
 	pos = digtron.find_new_pos(pos, facing)
 	if move_player then
 		clicker:moveto(digtron.find_new_pos(clicker:getpos(), facing), true)
 	end
-	
 	return pos, "", 0
 end

util_movement.lua

@@ -1,98 +0,0 @@
-digtron.move_node = function(pos, newpos, player_name)
-	-- Moves nodes, preserving digtron metadata and inventory
-	local node = minetest.get_node(pos)
-	local node_def = minetest.registered_nodes[node.name]
-	local oldnode = minetest.get_node(newpos)
-	minetest.log("action", string.format("%s moves %s from (%d, %d, %d) to (%d, %d, %d), displacing %s", player_name, node.name, pos.x, pos.y, pos.z, newpos.x, newpos.y, newpos.z, oldnode.name))
-	minetest.add_node(newpos, { name=node.name, param1=node.param1, param2=node.param2 })
-	-- copy the metadata
-	local oldmeta_table = minetest.get_meta(pos):to_table()
-	local meta = minetest.get_meta(newpos)
-	meta:from_table(oldmeta_table)
-	meta:set_string("waiting", nil) -- If a controller moves another controller that's in the waiting state, clear the waiting state otherwise it might get stuck like that (we've moved it away from the target of the pending 'clear the waiting state' delegate call). That means you can run a digtron as fast as you want by rapidly clicking between two different controllers, but shhh - don't tell the player that.
-
-	-- Move the little floaty entity inside the builders
-	if minetest.get_item_group(node.name, "digtron") == 4 then
-		digtron.update_builder_item(newpos)
-	end
-	
-	if node_def.after_place_node then
-		node_def.after_place_node(newpos)
-	end
-	
-	-- remove node from old position
-	minetest.remove_node(pos)
-	if node_def.after_dig_node then
-		node_def.after_dig_node(pos)
-	end
-end
-
-digtron.move_digtron = function(facing, digtrons, extents, nodes_dug, player_name)
-	-- move everything. Note! order is important or they'll step on each other, that's why this has complicated loops and filtering.
-	-- Nodes are moved in a "caterpillar" pattern - front plane first, then next plane back, then next plane back, etc.
-	-- positions in the digtron list will be updated when this method executes. Note that the inventories list shares
-	-- references to the node position tables in the digtron list, so it will reflect the updates too.
-	local dir = digtron.facedir_to_dir_map[facing]
-	local increment
-	local filter
-	local index
-	local target
-	if dir == 1 then -- z+
-		filter = "z"
-		increment = -1
-		index = extents.max_z
-		target = extents.min_z
-		extents.max_z = extents.max_z + 1
-		extents.min_z = extents.min_z + 1
-	elseif dir == 2 then -- x+
-		filter = "x"
-		increment = -1
-		index = extents.max_x
-		target = extents.min_x
-		extents.max_x = extents.max_x + 1
-		extents.min_x = extents.min_x + 1
-	elseif dir == 3 then -- z-
-		filter = "z"
-		increment = 1
-		index = extents.min_z
-		target = extents.max_z
-		extents.max_z = extents.max_z - 1
-		extents.min_z = extents.min_z - 1
-	elseif dir == 4 then -- x-
-		filter = "x"
-		increment = 1
-		index = extents.min_x
-		target = extents.max_x
-		extents.max_x = extents.max_x - 1
-		extents.min_x = extents.min_x - 1
-	elseif dir == 5 then -- y-
-		filter = "y"
-		increment = 1
-		index = extents.min_y
-		target = extents.max_y
-		extents.max_y = extents.max_y - 1
-		extents.min_y = extents.min_y - 1
-	elseif dir == 6 then -- y+
-		filter = "y"
-		increment = -1
-		index = extents.max_y
-		target = extents.min_y
-		extents.max_y = extents.max_y + 1
-		extents.min_y = extents.min_y + 1
-	end
-
-	while index ~= target + increment do
-		for k, location in pairs(digtrons) do
-			if location[filter] == index then
-				local newpos = digtron.find_new_pos(location, facing)
-				digtron.move_node(location, newpos, player_name)
-				--By updating the digtron position table in-place we also update all the special node tables as well
-				digtrons[k].x= newpos.x
-				digtrons[k].y= newpos.y
-				digtrons[k].z= newpos.z
-				nodes_dug:set(newpos.x, newpos.y, newpos.z, false) -- we've moved a digtron node into this space, mark it so that we don't dig it.
-			end
-		end
-		index = index + increment
-	end
-end