built on 23/06/2020 18:53:34

README.md

@@ -13,6 +13,7 @@ This modpack includes:
 - minecart: Techage transportation system for oil and other items
 - towercrane: Simplifies the building of large techage plants
 - basic_materials: Needed items for many recipes
+- stamina: The "hunger" mod from "minetest-mods"
 - doc: Ingame documentation mod, used for minecart and signs_bot
 - unified_inventory: Player's inventory with crafting guide, bags, and more.
 - tubelib2: Necessary library
@@ -40,6 +41,15 @@ Required: Minetest Game
 ### History
 
 
+#### 2020-06-23
+
+Updates (see local readme files):
+- mod stamina added
+- autobahn, towercrane and stamina now use a commen player physics lockout mechanism
+- signs_bot v1.03 with bugfixes
+- techage manual expanded
+
+
 #### 2020-06-21
 
 Updates (see local readme files):

autobahn/init.lua

@@ -36,19 +36,23 @@ end
 local function set_player_privs(player)
 	local physics = player:get_physics_override()
 	local meta = player:get_meta()
-	if meta and physics then
-		-- store the player privs default values
-		meta:set_int("autobahn_speed", physics.speed)
-		-- set operator privs
-		meta:set_int("autobahn_isactive", 1)
-		physics.speed = 3.5
-		minetest.sound_play("autobahn_motor", {
-				pos = player:get_pos(),
-				gain = 0.5,
-				max_hear_distance = 5,
-			})
-		-- write back
-		player:set_physics_override(physics)
+	-- Check access conflicts with other mods
+	if meta:get_int("player_physics_locked") == 0 then
+		meta:set_int("player_physics_locked", 1)
+		if meta and physics then
+			-- store the player privs default values
+			meta:set_int("autobahn_speed", physics.speed)
+			-- set operator privs
+			meta:set_int("autobahn_isactive", 1)
+			physics.speed = 3.5
+			minetest.sound_play("autobahn_motor", {
+					pos = player:get_pos(),
+					gain = 0.5,
+					max_hear_distance = 5,
+				})
+			-- write back
+			player:set_physics_override(physics)
+		end
 	end
 end
 
@@ -64,6 +68,7 @@ local function reset_player_privs(player)
 		meta:set_string("autobahn_speed", "")
 		-- write back
 		player:set_physics_override(physics)
+		meta:set_int("player_physics_locked", 0)
 	end
 end
 
@@ -79,6 +84,11 @@ minetest.register_on_leaveplayer(function(player)
 	end
 end)
 
+minetest.register_on_respawnplayer(function(player)
+	if is_active(player) then
+		reset_player_privs(player)
+	end
+end)
 
 local function control_player(player)
 	local player_name = player:get_player_name()
@@ -152,7 +162,7 @@ local function update_node(pos)
 	local nnode
 	local npos
 	-- check case 1
-	facedir = (2 + node.param2) % 4
+	local facedir = (2 + node.param2) % 4
 	npos = vector.add(pos, Facedir2Dir[facedir])
 	npos.y = npos.y - 1
 	nnode = minetest.get_node(npos)

player_physics_design_pattern.md

@@ -0,0 +1,71 @@
+# Player Physics Design Pattern
+
+To be able to control the access to player physics (like speed, gravity) and privs (like fast, fly)
+a common design pattern is used for the following mod-pack mods:
+
+- autobahn (fast, speed)
+- towercrane (fly, speed)
+- ta4_jetpack (gravity, speed)
+- stamina (resets the gravity/speed cyclically)
+- 3d_armor (changes physics based on APi calls)
+
+All of these mods try to change the player physics, which is a common resource and should only be changed by one mod.
+
+This lockout design pattern takes care that only one mod at a time is able to change physics or privs.
+
+```lua
+local function change_player_physics(player)
+	local physics = player:get_physics_override()
+	local meta = player:get_meta()
+	
+	-- Check access conflicts with other mods
+	if meta:get_int("player_physics_locked") == 0 then
+		meta:set_int("player_physics_locked", 1)
+
+        -- store old values, here speed and gravity
+		meta:set_int("mymod_normal_player_speed", physics.speed)
+		meta:set_int("mymod_normal_player_gravity", physics.gravity)
+
+		-- do whatever is needed
+        
+        player:set_physics_override(physics)
+        meta:set_int("mymod_is_active", 1)
+	end
+end
+
+local function restore_player_physics(player)
+	local physics = player:get_physics_override()
+	local meta = player:get_meta()
+	
+    if meta:get_int("mymod_is_active") == 1 then
+        meta:set_int("mymod_is_active", 0)
+
+        -- restore old values (speed and gravity)
+        physics.speed = meta:get_int("mymod_normal_player_speed")
+        physics.gravity = meta:get_int("mymod_normal_player_gravity")
+		player:set_physics_override(physics)
+    end
+	meta:set_int("player_physics_locked", 0)
+end
+
+
+
+minetest.register_on_joinplayer(function(player)
+	restore_player_physics(player)
+end)
+
+minetest.register_on_respawnplayer(function(player)
+	restore_player_physics(player)
+end)
+
+-- optional
+minetest.register_on_leaveplayer(function(player)
+	restore_player_physics(player)
+end)
+
+-- optional
+minetest.register_on_dieplayer(function(player)
+	restore_player_physics(player)
+end)
+```
+

stamina/.luacheckrc

@@ -0,0 +1,20 @@
+unused_args = false
+allow_defined_top = true
+
+read_globals = {
+	"DIR_DELIM",
+	"minetest",
+	"dump",
+	"vector", "nodeupdate",
+	"VoxelManip", "VoxelArea",
+	"PseudoRandom", "ItemStack",
+	"intllib",
+	"default",
+	"armor",
+	"player_monoids",
+}
+
+globals = {
+	minetest = { fields = { "do_item_eat" }},
+}
+

stamina/API.txt

@@ -0,0 +1,64 @@
+stamina.get_saturation(player)
+    Gets a player's saturation
+
+stamina.set_saturation(player, level)
+    Set a player's saturation.
+    Updates the HUD to reflect saturation level.
+
+stamina.update_saturation(player, level)
+    Update's a player's saturation.
+    Callbacks are processed first.
+
+stamina.change_saturation(player, change)
+    Update a player's saturation by a delta, instead of an absolute value.
+
+stamina.register_on_update_saturation(function(player, level))
+    Register a callback for when saturation is updated.
+    If the callback returns True, no further callbacks are called,
+    and the default behavior is bypassed.
+-----------------------
+stamina.is_poisoned(player)
+    Check if a player is poisoned
+
+stamina.set_poisoned(player, poisoned)
+    Set a player's "poisoned" status (boolean)
+    Updates the HUD to reflect poison status.
+
+stamina.poison(player, ticks, interval)
+    Poison a player for a certain amount of time.
+    Ticks is how many times to poison the player.
+    Interval is the time between poison ticks.
+    Processes callbacks before changing status.
+
+stamina.register_on_poison(function(player, ticks, interval))
+    Register a callback for when a player is poisoned.
+    If the callback returns True, no further callbacks are called,
+    and the default behavior is bypassed.
+-------------------------
+stamina.get_exhaustion(player)
+    Gets a player's exhaustion level.
+    Value is between 0 and `stamina.exhaust_lvl` (default: 160)
+
+stamina.set_exhaustion(player, level)
+    Sets a player's exhaustion level.
+
+stamina.exhaust_player(player, change, cause)
+    Update a player's exhaustion by "change".
+    If the player's exhaustion exceeds `stamina.exhaust_lvl`, stamina
+    is taken and exhaustion is reset.
+    Cause is an optional argument indicating the origin of the exhaustion.
+    Callbacks are processed before exhausting the player.
+
+stamina.register_on_exhaust_player(function(player, change, cause))
+    Register a callback for when exhaustion is updated.
+    If the callback returns True, no further callbacks are called,
+    and the default behavior is bypassed.
+------------------------
+stamina.set_sprinting(name, sprinting)
+    Sets whether a player is sprinting or not.
+    Callbacks are processed before setting sprint status.
+
+stamina.register_on_sprinting(function(player, sprinting))
+    Register a callback for when a player's sprinting status is updated.
+    If the callback returns True, no further callbacks are called,
+    and the default behavior is bypassed.

stamina/README.txt

@@ -0,0 +1,50 @@
+Minetest mod "Stamina"
+=====================
+
+(C) 2015 - BlockMen
+(C) 2016 - Auke Kok <sofar@foo-projects.org>
+
+
+About this mod:
+---------------
+This mod adds a stamina, or "hunger" mechanic to Minetest. Actions like
+crafting, walking, digging or fighting make the player exhausted. When
+enough exhaustion has been accumulated, the player gets more hungry,
+and loses stamina.
+
+If a player is low on stamina, they start taking periodical damage,
+and ultimately will die if they do not eat food.
+
+Eating food no longer heals the player. Instead, it increases the
+stamina of the player. The stamina bar shows how well fed the player
+is. More bread pieces means more stamina.
+
+
+Q&A time: Why won't I move the stamina bar to the right?
+
+Answer: this conflicts with the builtin breath bar. To move the
+builtin breath bar, I basically have to entirely re-implement it
+in lua including timers to catch breath changes for each online
+player, which is all a waste of time, just to move a few pixels
+around.
+
+
+For Modders:
+------------
+This mod intercepts minetest.item_eat(), and applies the hp_change
+as stamina change. The value can be positive (increase stamina) or
+negative (periodically damage the player by 1 hp).
+
+See API.txt for information on the API.
+
+License:
+--------
+Code:
+- all code LGPL-2.1+
+Textures:
+- stamina_hud_poison.png - BlockMen (CC-BY 3.0)
+- stamina_hud_fg.png - PilzAdam (WTFPL), modified by BlockMen
+- stamina_hud_bg.png - PilzAdam (WTFPL), modified by BlockMen
+Sounds:
+- stamina_eat.*.ogg - http://www.freesound.org/people/sonictechtonic/sounds/242215/ CC-BY-3.0
+

stamina/bower.json

@@ -0,0 +1,14 @@
+{
+    "name": "stamina",
+    "description": "This mod adds a stamina, or hunger mechanic to Minetest. Actions like crafting, walking, digging or fighting make the player exhausted.",
+    "homepage": "https://github.com/minetest-mods/stamina",
+    "authors": [
+        "BlockMen - 2015",
+        "Auke Kok - 2016"
+    ],
+    "license": "LGPL-2.1+",
+    "keywords": [
+        "hunger",
+        "stamina"
+    ]
+}

stamina/depends.txt

@@ -0,0 +1,3 @@
+default
+3d_armor?
+player_monoids?

stamina/description.txt

@@ -0,0 +1 @@
+Adds stamina and hunger effects.

stamina/init.lua

@@ -0,0 +1,552 @@
+if not minetest.settings:get_bool("enable_damage") then
+	minetest.log("warning", "[stamina] Stamina will not load if damage is disabled (enable_damage=false)")
+	return
+end
+
+stamina = {}
+local modname = minetest.get_current_modname()
+local armor_mod = minetest.get_modpath("3d_armor") and minetest.global_exists("armor") and armor.def
+local player_monoids_mod = minetest.get_modpath("player_monoids") and minetest.global_exists("player_monoids")
+
+function stamina.log(level, message, ...)
+	return minetest.log(level, ("[%s] %s"):format(modname, message:format(...)))
+end
+
+local function get_setting(key, default)
+	local value = minetest.settings:get("stamina." .. key)
+	local num_value = tonumber(value)
+	if value and not num_value then
+		stamina.log("warning", "Invalid value for setting %s: %q. Using default %q.", key, value, default)
+	end
+	return num_value or default
+end
+
+stamina.settings = {
+	-- see settingtypes.txt for descriptions
+	eat_particles = minetest.settings:get_bool("stamina.eat_particles", true),
+	sprint = minetest.settings:get_bool("stamina.sprint", true),
+	sprint_particles = minetest.settings:get_bool("stamina.sprint_particles", true),
+	sprint_lvl = get_setting("sprint_lvl", 6),
+	sprint_speed = get_setting("sprint_speed", 0.8),
+	sprint_jump = get_setting("sprint_jump", 0.1),
+	sprint_with_fast = minetest.settings:get_bool("stamina.sprint_with_fast", false),
+	tick = get_setting("tick", 800),
+	tick_min = get_setting("tick_min", 4),
+	health_tick = get_setting("health_tick", 4),
+	move_tick = get_setting("move_tick", 0.5),
+	poison_tick = get_setting("poison_tick", 2.0),
+	exhaust_dig = get_setting("exhaust_dig", 3),
+	exhaust_place = get_setting("exhaust_place", 1),
+	exhaust_move = get_setting("exhaust_move", 1.5),
+	exhaust_jump = get_setting("exhaust_jump", 5),
+	exhaust_craft = get_setting("exhaust_craft", 20),
+	exhaust_punch = get_setting("exhaust_punch", 40),
+	exhaust_sprint = get_setting("exhaust_sprint", 28),
+	exhaust_lvl = get_setting("exhaust_lvl", 160),
+	heal = get_setting("heal", 1),
+	heal_lvl = get_setting("heal_lvl", 5),
+	starve = get_setting("starve", 1),
+	starve_lvl = get_setting("starve_lvl", 3),
+	visual_max = get_setting("visual_max", 20),
+}
+local settings = stamina.settings
+
+local attribute = {
+	saturation = "stamina:level",
+	poisoned = "stamina:poisoned",
+	exhaustion = "stamina:exhaustion",
+}
+
+local function is_player(player)
+	return (
+		minetest.is_player(player) and
+		not player.is_fake_player
+	)
+end
+
+local function set_player_attribute(player, key, value)
+	if player.get_meta then
+		if value == nil then
+			player:get_meta():set_string(key, "")
+		else
+			player:get_meta():set_string(key, tostring(value))
+		end
+	else
+		player:set_attribute(key, value)
+	end
+end
+
+local function get_player_attribute(player, key)
+	if player.get_meta then
+		return player:get_meta():get_string(key)
+	else
+		return player:get_attribute(key)
+	end
+end
+
+local hud_ids_by_player_name = {}
+
+local function get_hud_id(player)
+	return hud_ids_by_player_name[player:get_player_name()]
+end
+
+local function set_hud_id(player, hud_id)
+	hud_ids_by_player_name[player:get_player_name()] = hud_id
+end
+
+--- SATURATION API ---
+function stamina.get_saturation(player)
+	return tonumber(get_player_attribute(player, attribute.saturation))
+end
+
+function stamina.set_saturation(player, level)
+	set_player_attribute(player, attribute.saturation, level)
+	player:hud_change(
+		get_hud_id(player),
+		"number",
+		math.min(settings.visual_max, level)
+	)
+end
+
+stamina.registered_on_update_saturations = {}
+function stamina.register_on_update_saturation(fun)
+	table.insert(stamina.registered_on_update_saturations, fun)
+end
+
+function stamina.update_saturation(player, level)
+	for _, callback in ipairs(stamina.registered_on_update_saturations) do
+		local result = callback(player, level)
+		if result then
+			return result
+		end
+	end
+
+	local old = stamina.get_saturation(player)
+
+	if level == old then  -- To suppress HUD update
+		return
+	end
+
+	-- players without interact priv cannot eat
+	if old < settings.heal_lvl and not minetest.check_player_privs(player, {interact=true}) then
+		return
+	end
+
+	stamina.set_saturation(player, level)
+end
+
+function stamina.change_saturation(player, change)
+	if not is_player(player) or not change or change == 0 then
+		return false
+	end
+	local level = stamina.get_saturation(player) + change
+	level = math.max(level, 0)
+	level = math.min(level, settings.visual_max)
+	stamina.update_saturation(player, level)
+	return true
+end
+
+stamina.change = stamina.change_saturation -- for backwards compatablity
+--- END SATURATION API ---
+--- POISON API ---
+function stamina.is_poisoned(player)
+	return get_player_attribute(player, attribute.poisoned) == "yes"
+end
+
+function stamina.set_poisoned(player, poisoned)
+	local hud_id = get_hud_id(player)
+	if poisoned then
+		player:hud_change(hud_id, "text", "stamina_hud_poison.png")
+		set_player_attribute(player, attribute.poisoned, "yes")
+	else
+		player:hud_change(hud_id, "text", "stamina_hud_fg.png")
+		set_player_attribute(player, attribute.poisoned, "no")
+	end
+end
+
+local function poison_tick(player, ticks, interval, elapsed)
+	if not stamina.is_poisoned(player) then
+		return
+	elseif elapsed > ticks then
+		stamina.set_poisoned(player, false)
+	else
+		local hp = player:get_hp() - 1
+		if hp > 0 then
+			player:set_hp(hp)
+		end
+		minetest.after(interval, poison_tick, player, ticks, interval, elapsed + 1)
+	end
+end
+
+stamina.registered_on_poisons = {}
+function stamina.register_on_poison(fun)
+	table.insert(stamina.registered_on_poisons, fun)
+end
+
+function stamina.poison(player, ticks, interval)
+	for _, fun in ipairs(stamina.registered_on_poisons) do
+		local rv = fun(player, ticks, interval)
+		if rv == true then
+			return
+		end
+	end
+	if not is_player(player) then
+		return
+	end
+	stamina.set_poisoned(player, true)
+	poison_tick(player, ticks, interval, 0)
+end
+--- END POISON API ---
+--- EXHAUSTION API ---
+stamina.exhaustion_reasons = {
+	craft = "craft",
+	dig = "dig",
+	heal = "heal",
+	jump = "jump",
+	move = "move",
+	place = "place",
+	punch = "punch",
+	sprint = "sprint",
+}
+
+function stamina.get_exhaustion(player)
+	return tonumber(get_player_attribute(player, attribute.exhaustion))
+end
+
+function stamina.set_exhaustion(player, exhaustion)
+	set_player_attribute(player, attribute.exhaustion, exhaustion)
+end
+
+stamina.registered_on_exhaust_players = {}
+function stamina.register_on_exhaust_player(fun)
+	table.insert(stamina.registered_on_exhaust_players, fun)
+end
+
+function stamina.exhaust_player(player, change, cause)
+	for _, callback in ipairs(stamina.registered_on_exhaust_players) do
+		local result = callback(player, change, cause)
+		if result then
+			return result
+		end
+	end
+
+	if not is_player(player) then
+		return
+	end
+
+	local exhaustion = stamina.get_exhaustion(player) or 0
+
+	exhaustion = exhaustion + change
+
+	if exhaustion >= settings.exhaust_lvl then
+		exhaustion = exhaustion - settings.exhaust_lvl
+		stamina.change(player, -1)
+	end
+
+	stamina.set_exhaustion(player, exhaustion)
+end
+--- END EXHAUSTION API ---
+--- SPRINTING API ---
+stamina.registered_on_sprintings = {}
+function stamina.register_on_sprinting(fun)
+	table.insert(stamina.registered_on_sprintings, fun)
+end
+
+function stamina.set_sprinting(player, sprinting)
+	for _, fun in ipairs(stamina.registered_on_sprintings) do
+		local rv = fun(player, sprinting)
+		if rv == true then
+			return
+		end
+	end
+
+	if player_monoids_mod then
+		if sprinting then
+			player_monoids.speed:add_change(player, 1 + settings.sprint_speed, "stamina:physics")
+			player_monoids.jump:add_change(player, 1 + settings.sprint_jump, "stamina:physics")
+		else
+			player_monoids.speed:del_change(player, "stamina:physics")
+			player_monoids.jump:del_change(player, "stamina:physics")
+		end
+	else
+		local def
+		if armor_mod then
+			-- Get player physics from 3d_armor mod
+			local name = player:get_player_name()
+			def = {
+				speed=armor.def[name].speed,
+				jump=armor.def[name].jump,
+				gravity=armor.def[name].gravity
+			}
+		else
+			def = {
+				speed=1,
+				jump=1,
+				gravity=1
+			}
+		end
+
+		if sprinting then
+			def.speed = def.speed + settings.sprint_speed
+			def.jump = def.jump + settings.sprint_jump
+		end
+
+		-- Check access conflicts with other mods
+		if player:get_meta():get_int("player_physics_locked") == 0 then
+			player:set_physics_override(def)
+		end
+	end
+
+	if settings.sprint_particles and sprinting then
+		local pos = player:getpos()
+		local node = minetest.get_node({x = pos.x, y = pos.y - 1, z = pos.z})
+		local def = minetest.registered_nodes[node.name] or {}
+		local drawtype = def.drawtype
+		if drawtype ~= "airlike" and drawtype ~= "liquid" and drawtype ~= "flowingliquid" then
+			minetest.add_particlespawner({
+				amount = 5,
+				time = 0.01,
+				minpos = {x = pos.x - 0.25, y = pos.y + 0.1, z = pos.z - 0.25},
+				maxpos = {x = pos.x + 0.25, y = pos.y + 0.1, z = pos.z + 0.25},
+				minvel = {x = -0.5, y = 1, z = -0.5},
+				maxvel = {x = 0.5, y = 2, z = 0.5},
+				minacc = {x = 0, y = -5, z = 0},
+				maxacc = {x = 0, y = -12, z = 0},
+				minexptime = 0.25,
+				maxexptime = 0.5,
+				minsize = 0.5,
+				maxsize = 1.0,
+				vertical = false,
+				collisiondetection = false,
+				texture = "default_dirt.png",
+			})
+		end
+	end
+end
+--- END SPRINTING API ---
+
+-- Time based stamina functions
+local function move_tick()
+	for _,player in ipairs(minetest.get_connected_players()) do
+		local controls = player:get_player_control()
+		local is_moving = controls.up or controls.down or controls.left or controls.right
+		local velocity = player:get_player_velocity()
+		velocity.y = 0
+		local horizontal_speed = vector.length(velocity)
+		local has_velocity = horizontal_speed > 0.05
+
+		if controls.jump then
+			stamina.exhaust_player(player, settings.exhaust_jump, stamina.exhaustion_reasons.jump)
+		elseif is_moving and has_velocity then
+			stamina.exhaust_player(player, settings.exhaust_move, stamina.exhaustion_reasons.move)
+		end
+
+		if settings.sprint then
+			local can_sprint = (
+				controls.aux1 and
+				not player:get_attach() and
+				(settings.sprint_with_fast or not minetest.check_player_privs(player, {fast = true})) and
+				stamina.get_saturation(player) > settings.sprint_lvl
+			)
+
+			if can_sprint then
+				stamina.set_sprinting(player, true)
+				if is_moving and has_velocity then
+					stamina.exhaust_player(player, settings.exhaust_sprint, stamina.exhaustion_reasons.sprint)
+				end
+			else
+				stamina.set_sprinting(player, false)
+			end
+		end
+	end
+end
+
+local function stamina_tick()
+	-- lower saturation by 1 point after settings.tick second(s)
+	for _,player in ipairs(minetest.get_connected_players()) do
+		local saturation = stamina.get_saturation(player)
+		if saturation > settings.tick_min then
+			stamina.update_saturation(player, saturation - 1)
+		end
+	end
+end
+
+local function health_tick()
+	-- heal or damage player, depending on saturation
+	for _,player in ipairs(minetest.get_connected_players()) do
+		local air = player:get_breath() or 0
+		local hp = player:get_hp()
+		local saturation = stamina.get_saturation(player)
+
+		-- don't heal if dead, drowning, or poisoned
+		local should_heal = (
+			saturation >= settings.heal_lvl and
+			saturation >= hp and
+			hp > 0 and
+			air > 0
+			and not stamina.is_poisoned(player)
+		)
+		-- or damage player by 1 hp if saturation is < 2 (of 30)
+		local is_starving = (
+			saturation < settings.starve_lvl and
+			hp > 0
+		)
+
+		if should_heal then
+			player:set_hp(hp + settings.heal)
+			stamina.exhaust_player(player, settings.exhaust_lvl, stamina.exhaustion_reasons.heal)
+		elseif is_starving then
+			player:set_hp(hp - settings.starve)
+		end
+	end
+end
+
+local stamina_timer = 0
+local health_timer = 0
+local action_timer = 0
+
+local function stamina_globaltimer(dtime)
+	stamina_timer = stamina_timer + dtime
+	health_timer = health_timer + dtime
+	action_timer = action_timer + dtime
+
+	if action_timer > settings.move_tick then
+		action_timer = 0
+		move_tick()
+	end
+
+	if stamina_timer > settings.tick then
+		stamina_timer = 0
+		stamina_tick()
+	end
+
+	if health_timer > settings.health_tick then
+		health_timer = 0
+		health_tick()
+	end
+end
+
+-- override minetest.do_item_eat() so we can redirect hp_change to stamina
+stamina.core_item_eat = minetest.do_item_eat
+function minetest.do_item_eat(hp_change, replace_with_item, itemstack, player, pointed_thing)
+	for _, callback in ipairs(minetest.registered_on_item_eats) do
+		local result = callback(hp_change, replace_with_item, itemstack, player, pointed_thing)
+		if result then
+			return result
+		end
+	end
+
+	if not is_player(player) or not itemstack then
+		return itemstack
+	end
+
+	local level = stamina.get_saturation(player) or 0
+	if level >= settings.visual_max then
+		-- don't eat if player is full
+		return itemstack
+	end
+
+	local itemname = itemstack:get_name()
+	if replace_with_item then
+		stamina.log("action", "%s eats %s for %s stamina, replace with %s",
+			player:get_player_name(), itemname, hp_change, replace_with_item)
+	else
+		stamina.log("action", "%s eats %s for %s stamina",
+			player:get_player_name(), itemname, hp_change)
+	end
+	minetest.sound_play("stamina_eat", {to_player = player:get_player_name(), gain = 0.7})
+
+	if hp_change > 0 then
+		stamina.change_saturation(player, hp_change)
+		stamina.set_exhaustion(player, 0)
+	else
+		-- assume hp_change < 0.
+		stamina.poison(player, -hp_change, settings.poison_tick)
+	end
+
+	if settings.eat_particles then
+		-- particle effect when eating
+		local pos = player:getpos()
+		pos.y = pos.y + 1.5 -- mouth level
+		local texture  = minetest.registered_items[itemname].inventory_image
+		local dir = player:get_look_dir()
+
+		minetest.add_particlespawner({
+			amount = 5,
+			time = 0.1,
+			minpos = pos,
+			maxpos = pos,
+			minvel = {x = dir.x - 1, y = dir.y, z = dir.z - 1},
+			maxvel = {x = dir.x + 1, y = dir.y, z = dir.z + 1},
+			minacc = {x = 0, y = -5, z = 0},
+			maxacc = {x = 0, y = -9, z = 0},
+			minexptime = 1,
+			maxexptime = 1,
+			minsize = 1,
+			maxsize = 2,
+			texture = texture,
+		})
+	end
+
+	itemstack:take_item()
+
+	if replace_with_item then
+		if itemstack:is_empty() then
+			itemstack:add_item(replace_with_item)
+		else
+			local inv = player:get_inventory()
+			if inv:room_for_item("main", {name=replace_with_item}) then
+				inv:add_item("main", replace_with_item)
+			else
+				local pos = player:getpos()
+				pos.y = math.floor(pos.y - 1.0)
+				minetest.add_item(pos, replace_with_item)
+			end
+		end
+	end
+
+	return itemstack
+end
+
+minetest.register_on_joinplayer(function(player)
+	local level = stamina.get_saturation(player) or settings.visual_max
+	local id = player:hud_add({
+		name = "stamina",
+		hud_elem_type = "statbar",
+		position = {x = 0.5, y = 1},
+		size = {x = 24, y = 24},
+		text = "stamina_hud_fg.png",
+		number = level,
+		alignment = {x = -1, y = -1},
+		offset = {x = -266, y = -110},
+		max = 0,
+	})
+	stamina.set_saturation(player, level)
+	set_hud_id(player, id)
+	-- reset poisoned
+	stamina.set_poisoned(player, false)
+	-- remove legacy hud_id from player metadata
+	set_player_attribute(player, "stamina:hud_id", nil)
+end)
+
+minetest.register_on_leaveplayer(function(player)
+	set_hud_id(player, nil)
+end)
+
+minetest.register_globalstep(stamina_globaltimer)
+
+minetest.register_on_placenode(function(pos, oldnode, player, ext)
+	stamina.exhaust_player(player, settings.exhaust_place, stamina.exhaustion_reasons.place)
+end)
+minetest.register_on_dignode(function(pos, oldnode, player, ext)
+	stamina.exhaust_player(player, settings.exhaust_dig, stamina.exhaustion_reasons.dig)
+end)
+minetest.register_on_craft(function(itemstack, player, old_craft_grid, craft_inv)
+	stamina.exhaust_player(player, settings.exhaust_craft, stamina.exhaustion_reasons.craft)
+end)
+minetest.register_on_punchplayer(function(player, hitter, time_from_last_punch, tool_capabilities, dir, damage)
+	stamina.exhaust_player(hitter, settings.exhaust_punch, stamina.exhaustion_reasons.punch)
+end)
+minetest.register_on_respawnplayer(function(player)
+	stamina.update_saturation(player, settings.visual_max)
+end)

stamina/mod.conf

@@ -0,0 +1 @@
+name = stamina

stamina/settingtypes.txt

@@ -0,0 +1,24 @@
+stamina.enabled          (Is stamina enabled?)                                    bool true
+stamina.sprint           (Is sprint enabled?)                                     bool true
+stamina.sprint_particles (Are sprint particles enabled?)                          bool true
+stamina.tick             (time in seconds after that 1 saturation point is taken) float 800
+stamina.tick_min         (stamina ticks won't reduce saturation below this level) int 4
+stamina.health_tick      (time in seconds after player gets healed/damaged)       float 4
+stamina.move_tick        (time in seconds after the movement is checked)          float 0.5
+stamina.exhaust_dig      (exhaustion for digging a node)                          float 3
+stamina.exhaust_place    (exhaustion for placing a node)                          float 1
+stamina.exhaust_move     (exhaustion for moving)                                  float 1.5
+stamina.exhaust_jump     (exhaustion for jumping)                                 float 5
+stamina.exhaust_craft    (exhaustion for crafting)                                float 20
+stamina.exhaust_punch    (exhaustion for punching)                                float 40
+stamina.exhaust_sprint   (exhaustion for sprinting)                               float 28
+stamina.exhaust_lvl      (exhaustion level at which saturation gets lowered)      float 160
+stamina.heal             (amount of HP a player gains per stamina.health_tick)    int 1 0 20
+stamina.heal_lvl         (minimum saturation needed for healing)                  int 5 1 20
+stamina.starve           (amount of HP a player loses per stamina.health_tick)    int 1 0 20
+stamina.starve_lvl       (maximum stamina needed for starving)                    int 3 0 19
+stamina.visual_max       (hud bar only extends to 20)                             int 20 2 20
+stamina.sprint_speed     (how much faster a player can run if satiated)           float 0.8  0 2
+stamina.sprint_jump      (how much faster a player can jump if satiated)          float 0.1  0 2
+stamina.eat_particles    (Whether to generate particles when eating)              bool true
+stamina.sprint_with_fast (Sprint when player has fast privilege?)                 bool false

towercrane/control.lua

@@ -71,21 +71,27 @@ local function set_operator_privs(player, pos)
 	local privs = minetest.get_player_privs(player:get_player_name())
 	local physics = player:get_physics_override()
 	local meta = player:get_meta()
-	if pos and meta and privs and physics then
-		meta:set_string("towercrane_pos", P2S(pos))
-		-- store the player privs default values
-		meta:set_string("towercrane_fast", privs["fast"] and "true" or "false")
-		meta:set_string("towercrane_fly", privs["fly"] and "true" or "false")
-		meta:set_int("towercrane_speed", physics.speed)
-		-- set operator privs
-		meta:set_int("towercrane_isoperator", 1)
-		privs["fly"] = true
-		privs["fast"] = nil
-		physics.speed = 0.7
-		-- write back
-		player:set_physics_override(physics)
-		minetest.set_player_privs(player:get_player_name(), privs)
+	-- Check access conflicts with other mods
+	if meta:get_int("player_physics_locked") == 0 then 
+		if pos and meta and privs and physics then
+			meta:set_string("towercrane_pos", P2S(pos))
+			-- store the player privs default values
+			meta:set_string("towercrane_fast", privs["fast"] and "true" or "false")
+			meta:set_string("towercrane_fly", privs["fly"] and "true" or "false")
+			meta:set_int("towercrane_speed", physics.speed)
+			-- set operator privs
+			meta:set_int("towercrane_isoperator", 1)
+			meta:set_int("player_physics_locked", 1)
+			privs["fly"] = true
+			privs["fast"] = nil
+			physics.speed = 0.7
+			-- write back
+			player:set_physics_override(physics)
+			minetest.set_player_privs(player:get_player_name(), privs)
+			return true
+		end
 	end
+	return false
 end
 
 local function reset_operator_privs(player)
@@ -96,6 +102,7 @@ local function reset_operator_privs(player)
 		meta:set_string("towercrane_pos", "")
 		-- restore the player privs default values
 		meta:set_int("towercrane_isoperator", 0)
+		meta:set_int("player_physics_locked", 0)
 		privs["fast"] = meta:get_string("towercrane_fast") == "true" or nil
 		privs["fly"] = meta:get_string("towercrane_fly") == "true" or nil
 		physics.speed = meta:get_int("towercrane_speed")
@@ -275,10 +282,11 @@ minetest.register_node("towercrane:mast_ctrl_off", {
 	on_rightclick = function (pos, node, clicker)
 		if is_my_crane(pos, clicker) and not is_operator(clicker) then
 			start_crane(pos, clicker)
-			set_operator_privs(clicker, pos)
-			local pos1, pos2 = calc_construction_area(pos)
-			-- control player every second
-			minetest.after(1, control_player, pos, pos1, pos2, clicker:get_player_name())
+			if set_operator_privs(clicker, pos) then
+				local pos1, pos2 = calc_construction_area(pos)
+				-- control player every second
+				minetest.after(1, control_player, pos, pos1, pos2, clicker:get_player_name())
+			end
 		end
 	end,