Add more "rip nodes in radius" functionality

Refactor out the single "rip radius now"
command, and add one that works
constantly while the player is walking, so
e.g. a player can explore an existing map
or load schematics and rip their nodes
automatically.

commands.lua

@@ -1,6 +1,6 @@
 -- LUALOCALS < ---------------------------------------------------------
-local minetest, pairs, pcall, string, tonumber, vector
-    = minetest, pairs, pcall, string, tonumber, vector
+local minetest, next, pairs, pcall, string, tonumber, vector
+    = minetest, next, pairs, pcall, string, tonumber, vector
 local string_format, string_gsub, string_match
     = string.format, string.gsub, string.match
 -- LUALOCALS > ---------------------------------------------------------
@@ -49,35 +49,6 @@ minetest.register_chatcommand(modname .. "_inv", {
 		end
 	})
 
-minetest.register_chatcommand(modname .. "_here", {
-		description = "Rip all nodes within a radius",
-		params = "[radius = 100]",
-		privs = {server = true},
-		func = function(name, param)
-			local player = minetest.get_player_by_name(name)
-			if not player then return false, "invalid player" end
-
-			local radius = tonumber(param) or 100
-			local pos = player:get_pos()
-
-			local foundids = {}
-			do
-				local vm = minetest.get_voxel_manip(
-					vector.subtract(pos, radius),
-					vector.add(pos, radius))
-				local data = vm:get_data()
-				for i = 1, #data do foundids[data[i]] = true end
-			end
-
-			for k in pairs(foundids) do
-				local n = minetest.get_name_from_content_id(k)
-				if n then exportdb[n] = true end
-			end
-
-			return save_export_report()
-		end
-	})
-
 local function patternfunc(setto)
 	return function(_, param)
 		if param == "" then return false, "must supply pattern" end
@@ -104,3 +75,95 @@ minetest.register_chatcommand(modname .. "_rm", {
 		privs = {server = true},
 		func = patternfunc(nil)
 	})
+
+local function ripradius(pos, radius)
+	local foundids = {}
+	do
+		local vm = minetest.get_voxel_manip(
+			vector.subtract(pos, radius),
+			vector.add(pos, radius))
+		local data = vm:get_data()
+		for i = 1, #data do foundids[data[i]] = true end
+	end
+
+	local dirty
+	for k in pairs(foundids) do
+		local n = minetest.get_name_from_content_id(k)
+		if n and not exportdb[n] then
+			exportdb[n] = true
+			dirty = true
+		end
+	end
+
+	return dirty
+end
+
+minetest.register_chatcommand(modname .. "_here", {
+		description = "Rip all nodes within a radius",
+		params = "[radius_x=100 [radius_y=radius_x [radius_z=radius_x]]]",
+		privs = {server = true},
+		func = function(name, param)
+			local player = minetest.get_player_by_name(name)
+			if not player then return false, "invalid player" end
+
+			local parts = param:split(" ")
+			local rx = parts[1] and tonumber(parts[1]) or 100
+			local ry = parts[2] and tonumber(parts[2]) or rx
+			local rz = parts[3] and tonumber(parts[3]) or rx
+
+			ripradius(player:get_pos(), vector.new(rx, ry, rz))
+
+			return save_export_report()
+		end
+	})
+
+local steprippers = {}
+local stepripstart
+do
+	local pended
+	local function stepriprun()
+		pended = false
+		if next(steprippers) == nil then return end
+
+		for pname, pdata in pairs(steprippers) do
+			local player = minetest.get_player_by_name(pname)
+			if player then
+				local pos = player:get_pos()
+				local oldpos = pdata.pos
+				if (not oldpos) or (vector.distance(pos, oldpos) >= pdata.step) then
+					pdata.pos = pos
+					if ripradius(pos, pdata.radius) then
+						minetest.chat_send_player(pname, "exporting...")
+						local _, rpt = save_export_report()
+						minetest.chat_send_player(pname, rpt)
+					end
+				end
+			end
+		end
+
+		return stepripstart()
+	end
+	stepripstart = function()
+		if pended then return end
+		minetest.after(0, stepriprun)
+		pended = true
+	end
+end
+
+minetest.register_chatcommand(modname .. "_step", {
+		description = "Rip nodes in radius every step",
+		params = "[radius_x=100 [radius_y=radius_x [radius_z=radius_x [stepsize=2]]]]",
+		privs = {server = true},
+		func = function(name, param)
+			local parts = param:split(" ")
+			local rx = parts[1] and tonumber(parts[1]) or 100
+			local ry = parts[2] and tonumber(parts[2]) or rx
+			local rz = parts[3] and tonumber(parts[3]) or rx
+
+			steprippers[name] = rx > 0 and {
+				radius = vector.new(rx, ry, rz),
+				step = parts[4] and tonumber(parts[4]) or 2
+			} or nil
+			stepripstart()
+		end
+	})