Rewrite fallout algorithm to be more stable

CREDITS.md

@@ -162,6 +162,9 @@ All levels by Wuzzy.
 - `lzr_menu_speaker_turn_off.ogg`:
 	- by mincedbeats <https://freesound.org/people/mincedbeats/sounds/593996/>
 	- License: CC0
+- `lzr_fallout_damage.ogg`:
+	- by newagesoup <https://freesound.org/people/newagesoup/sounds/348242/>
+	- License: CC0
 
 - All other sounds come from Minetest Game (see license of Minetest Game 5.4.1 for details)
 

mods/lzr_fallout/init.lua

@@ -1,89 +1,187 @@
--- Periodically check the player position if it is in the valid range.
--- For example, if the player "fell out" of the level.
+-- Periodically check the player position is valid.
+-- A position is invalid if the player:
+-- * Is out of level bounds
+-- * Is below a defined Y coordinate in the ship
+-- * Has their head in a solid node
 --
--- If the player is out of range, then:
--- * In the menu ship: Teleport back to ship spawn
+-- If the player is in an invalid place, then:
+-- * In the menu ship: Teleport back to ship spawn. Happens quickly
 -- * In a level: Fail level, teleport back to ship and taunt player
+--   This happens only if the player was out of bounds for
+--   a few consecutive seconds.
 -- * Any other game state: Do nothing
 --
--- Additionally, it is checked whether the player head is stuck
--- in a solid node.
---
 -- Having the fly or noclip privs bypasses all resets.
+--
+--
+-- This mod exists for multiple reasons:
+-- 1) Work with all levels: Even with badly-designed
+-- levels where the player can somehow escape or
+-- spawns in solid rock, the game ensures the
+-- level fails automatically.
+-- 2) "Lose" a level: The player can legitimately make
+-- themselves stuck by triggering skulls into walkable
+-- mode, right where they stand. If you're surrounded
+-- by activated cursed ckulls, it's impossible to win, so the
+-- level must fail. But there is still a chance the player
+-- can fix this by jumping or walking out if not
+-- *completely* surrounded, which is why the damage
+-- system has been added (see below)
 
 local S = minetest.get_translator("lzr_fallout")
 
-local CRUSH_TIMER = 3
-local FALLOUT_TIMER = 2
+-- If the player is in the ship, fallout occurs when below this Y
 local SHIP_FALLOUT_Y = lzr_globals.MENU_SHIP_POS.y + lzr_globals.MENU_SHIP_FALLOUT_Y_OFFSET
 
-local timer = 0
+-- In a level, players in an invalid position do not immediately
+-- fail but first take "damage" as long they are in danger.
+-- Only once PLAYER_MAX_DAMAGE was surpassed, the failure is triggered.
+
+-- Note this game does NOT use regular damage and health, as defined
+-- by Minetest, it's disabled. The "damage" here applies only to this mod!
+local PLAYER_MAX_DAMAGE = 3
+
+-- Player damage increases roughly every second the player is in danger,
+-- and decreases while out of danger
+local player_damage = 0
+
+-- Count the time for how long the player is being crushed, out of bounds
+-- or safe (=not in any danger).
 local crush_timer = 0
+local out_of_bounds_timer = 0
+local safe_timer = 0
+
+local reset_player = function(player, reset_type)
+	if reset_type == "fallout_ship" then
+		local spawn = vector.add(lzr_globals.MENU_SHIP_POS, lzr_globals.MENU_SHIP_PLAYER_SPAWN_OFFSET)
+		player:set_pos(spawn)
+	elseif reset_type == "fallout" then
+		lzr_messages.show_message(player, S("You’re sleeping with the fishes!"), 6.0, 0xFF0000)
+		lzr_levels.leave_level()
+	elseif reset_type == "out_of_bounds" then
+		lzr_messages.show_message(player, S("Where yer thinks yar goin’, landlubber?"), 6.0, 0xFF0000)
+		lzr_levels.leave_level()
+	elseif reset_type == "skull_crush" then
+		lzr_messages.show_message(player, S("You were skull-crushed!"), 6.0, 0xFF0000)
+		lzr_levels.leave_level()
+	elseif reset_type == "crush" then
+		lzr_messages.show_message(player, S("You were between a rock and a hard place."), 6.0, 0xFF0000)
+		lzr_levels.leave_level()
+	else
+		minetest.log("error", "[lzr_fallout] reset_player called with unknown reset_type: "..tostring(reset_type))
+	end
+	crush_timer = 0
+	out_of_bounds_timer = 0
+	player_damage = 0
+	safe_timer = 0
+end
+
+local step_timer = 0
 minetest.register_globalstep(function(dtime)
-	timer = timer + dtime
-	if timer < FALLOUT_TIMER then
+	local ddtime = dtime + step_timer
+	step_timer = step_timer + dtime
+	if step_timer < 1 then
 		return
 	end
-	timer = 0
+	step_timer = 0
+
 	local players = minetest.get_connected_players()
 	local state = lzr_gamestate.get_state()
+	if state == lzr_gamestate.EDITOR or state == lzr_gamestate.SHUTDOWN or state == lzr_gamestate.LEVEL_COMPLETE then
+		return
+	end
 	for p=1, #players do
 		local player = players[p]
 		local privs = minetest.get_player_privs(player:get_player_name())
 		if not (privs["fly"] or privs["noclip"]) then
 			local pos = player:get_pos()
+			local reset_type
 			if state == lzr_gamestate.MENU then
+				-- If fallen out of ship, reset immediately
 				if pos.y < SHIP_FALLOUT_Y then
-					local spawn = vector.add(lzr_globals.MENU_SHIP_POS, lzr_globals.MENU_SHIP_PLAYER_SPAWN_OFFSET)
-					player:set_pos(spawn)
+					reset_type = "fallout_ship"
+					reset_player(player, reset_type)
 				end
 				crush_timer = 0
+				out_of_bounds_timer = 0
+				player_damage = 0
+				safe_timer = 0
 			elseif state == lzr_gamestate.LEVEL then
 				-- Below allowed minimum Y
 				if pos.y < lzr_globals.LEVEL_FALLOUT_Y then
-					lzr_messages.show_message(player, S("You are sleeping with the fishes!"), 6.0, 0xFF0000)
-					lzr_levels.leave_level()
-					crush_timer = 0
-					return
+					out_of_bounds_timer = out_of_bounds_timer + ddtime
+					reset_type = "fallout"
 				else
 					-- Outside of level bounds in other directions
 					local minpos = lzr_globals.LEVEL_POS
 					local maxpos = vector.add(lzr_globals.LEVEL_POS, lzr_levels.get_level_size())
 					if pos.x < minpos.x -0.5 or pos.x > maxpos.x + 0.5 or pos.z < minpos.z -0.5 or pos.z > maxpos.z + 0.5 or pos.y > maxpos.y + 0.5 then
-						lzr_messages.show_message(player, S("Where yer thinks yar goin’, landlubber?"), 6.0, 0xFF0000)
-						lzr_levels.leave_level()
-						crush_timer = 0
-						return
+						out_of_bounds_timer = out_of_bounds_timer + ddtime
+						reset_type = "out_of_bounds"
 					else
-						-- Player head got stuck in solid node for a few seconds
-						local node2 = minetest.get_node(vector.offset(pos, 0, 1, 0))
-						local def2 = minetest.registered_nodes[node2.name]
-						if def2 and def2.walkable and minetest.get_item_group(node2.name, "slab") == 0 and minetest.get_item_group(node2.name, "stair") == 0 and minetest.get_item_group(node2.name, "takable") == 0 then
-							-- Stuck in solid skull: No further delay
-							if minetest.get_item_group(node2.name, "skull") ~= 0 then
-								lzr_messages.show_message(player, S("You were skull-crushed!"), 6.0, 0xFF0000)
-								lzr_levels.leave_level()
-								crush_timer = 0
-								return
-							end
-							-- Stuck in other solid node: After a short time
-							-- Only full-size nodes count
-							if (not def2.collision_box and not def2.node_box) or (def2.collision_box and def2.collision_box.type == "regular") or (not def2.collision_box and def2.node_box and def2.node_box.type == "regular") then
-								crush_timer = crush_timer + FALLOUT_TIMER + dtime
-								if crush_timer > CRUSH_TIMER then
-									lzr_messages.show_message(player, S("You were between a rock and a hard place."), 6.0, 0xFF0000)
-									lzr_levels.leave_level()
-									crush_timer = 0
-									return
-								end
-							end
-						else
-							crush_timer = 0
-						end
+						out_of_bounds_timer = 0
+					end
+				end
+
+				-- Player head got stuck in solid node
+				local node2 = minetest.get_node(vector.offset(pos, 0, 1, 0))
+				local def2 = minetest.registered_nodes[node2.name]
+				if def2 and def2.walkable and minetest.get_item_group(node2.name, "slab") == 0 and minetest.get_item_group(node2.name, "stair") == 0 and minetest.get_item_group(node2.name, "takable") == 0 then
+					if minetest.get_item_group(node2.name, "skull") ~= 0 then
+						reset_type = "skull_crush"
+						crush_timer = crush_timer + ddtime
+					elseif (not def2.collision_box and not def2.node_box) or (def2.collision_box and def2.collision_box.type == "regular") or (not def2.collision_box and def2.node_box and def2.node_box.type == "regular") then
+						reset_type = "crush"
+						crush_timer = crush_timer + ddtime
+					else
+						crush_timer = 0
+					end
+				else
+					crush_timer = 0
+				end
+
+				local damage_player = function(player, reset_type)
+					player_damage = player_damage + 1
+					local gain
+					if player_damage >= 3 then
+						gain = 1
+					elseif player_damage >= 2 then
+						gain = 0.7
+					elseif player_damage >= 1 then
+						gain = 0.4
+					end
+					minetest.sound_play({name="lzr_fallout_damage", gain=gain}, {to_player=player:get_player_name()}, true)
+					if player_damage > PLAYER_MAX_DAMAGE then
+						reset_player(player, reset_type)
+					end
+				end
+
+				-- Being in an invalid place does not immediately trigger
+				-- a player reset, but first increases an internal damage
+				-- counter. Only if the damage exceeds a limit will
+				-- the player reset be triggered.
+				-- This gives the player a chance to get out of sticky situations.
+				if out_of_bounds_timer > 1 then
+					out_of_bounds_timer = 0
+					safe_timer = 0
+					damage_player(player, reset_type)
+				elseif crush_timer > 1 then
+					crush_timer = 0
+					safe_timer = 0
+					damage_player(player, reset_type)
+				elseif out_of_bounds_timer == 0 and crush_timer == 0 then
+					safe_timer = safe_timer + ddtime
+					if safe_timer > 1 then
+						-- Reduce damage when safe
+						player_damage = math.max(0, player_damage - 1)
+						safe_timer = 0
 					end
 				end
 			else
 				crush_timer = 0
+				out_of_bounds_timer = 0
+				safe_timer = 0
+				player_damage = 0
 			end
 		end
 	end