M1c: weather, snap building, shelter, beds and regrowth

- Seeded weather (clear/cloudy/rain/storm, snow and blizzards on cold days
  and above the snowline), lightning, synthesised rain/wind/thunder sound
- Rain/snow particles stopped by roofs; wet ground, settled snow and wind
  via global shader uniforms
- Snap-together wood floor, wall, door, roof and gable with structural
  support, collapse and X to dismantle
- Shelter detection: dry under a roof, warmer and Rested inside with a fire;
  rain burns an uncovered campfire faster
- Bed sets the spawn point and lets you sleep through the night
- Trees, boulders and ground pickups regrow; timers saved
- Grass cleared under floors; shorter HUD hint
- New test_weather_building suite (62 checks) and tests/run_all.sh, which
  also fails on script errors

scripts/player/hands.gd

@@ -11,6 +11,7 @@ extends Node3D
 signal prompt_changed(text: String)
 
 const Campfire = preload("res://scripts/building/campfire.gd")
+const BuildPiece = preload("res://scripts/building/build_piece.gd")
 const REACH := 3.2
 const PLACE_REACH := 6.0
 const SWING_TIME := 0.5
@@ -26,6 +27,7 @@ var _ghost_bad_mat: StandardMaterial3D
 var _ghost_yaw := 0.0
 var _place_xf := Transform3D()
 var _place_ok := false
+var _place_reason := ""
 var _prompt := ""
 var _held_shown := "~"
 var _torch_light: OmniLight3D
@@ -123,6 +125,8 @@ func _target() -> Object:
 	if not _ray.is_colliding():
 		return null
 	var c := _ray.get_collider()
+	if c != null and c.has_meta("owner_piece"):
+		c = c.get_meta("owner_piece")   # a door's moving panel
 	if c == null or not c.has_method("interact_prompt"):
 		return null
 	if c.get("depleted") == true:
@@ -138,7 +142,8 @@ func _physics_process(delta: float) -> void:
 	var def := _held_def()
 	if def.has("place"):
 		_update_ghost(def)
-		_set_prompt("[LMB] Place %s   [R] Rotate" % def.name)
+		var why := "" if _place_ok or _place_reason.is_empty() else "   (%s)" % _place_reason
+		_set_prompt("[LMB] Place %s   [R] Rotate%s" % [def.name, why])
 		return
 	_ghost.visible = false
 	if _torch_light.visible:
@@ -146,7 +151,10 @@ func _physics_process(delta: float) -> void:
 		_torch_light.light_energy = float(def.get("light", {}).get("energy", 1.5)) * (0.85 + 0.15 * sin(_t * 17.0) * sin(_t * 5.3))
 	var t := _target()
 	if t != null:
-		_set_prompt(t.interact_prompt(player))
+		var p: String = t.interact_prompt(player)
+		if t.is_in_group("piece") and t.item_id != "grave":
+			p += "   [X] Dismantle"
+		_set_prompt(p)
 	elif def.has("food"):
 		_set_prompt("[RMB] Eat %s" % def.name)
 	else:
@@ -163,8 +171,16 @@ func _update_ghost(def: Dictionary) -> void:
 		_place_ok = false
 		return
 	var yaw := player.rotation.y + _ghost_yaw   # piece's front (+Z) faces the player
-	_place_xf = Transform3D(Basis(Vector3.UP, yaw), hit.position)
-	_place_ok = player.get_parent().placement_valid(def, _place_xf)
+	if BuildPiece.is_build(def):
+		# Building pieces snap to what's already built (build_system.gd).
+		var res: Dictionary = player.get_parent().build.placement(def, hit, yaw)
+		_place_xf = res.xf
+		_place_ok = res.ok
+		_place_reason = res.reason
+	else:
+		_place_xf = Transform3D(Basis(Vector3.UP, yaw), hit.position)
+		_place_ok = player.get_parent().placement_valid(def, _place_xf)
+		_place_reason = "" if _place_ok else "blocked or too steep"
 	_ghost.global_transform = _place_xf
 	_ghost.material_override = _ghost_ok_mat if _place_ok else _ghost_bad_mat
 	_ghost.visible = true
@@ -185,7 +201,12 @@ func _unhandled_input(event: InputEvent) -> void:
 		if _held_def().has("food"):
 			Actions.eat(player, player.selected)
 	elif event.is_action_pressed("rotate_piece"):
-		_ghost_yaw += deg_to_rad(22.5)
+		# Building pieces turn in quarter turns (they snap to a grid).
+		_ghost_yaw += deg_to_rad(90.0 if BuildPiece.is_build(_held_def()) else 22.5)
+	elif event.is_action_pressed("dismantle"):
+		var t := _target()
+		if t != null and t.is_in_group("piece"):
+			Actions.dismantle(player, t)
 	elif event.is_action_pressed("interact"):
 		var t := _target()
 		if t != null and t.has_method("interact"):

scripts/player/survival.gd

@@ -19,6 +19,8 @@ const HUNGER_DRAIN := 100.0 / 1500.0   ## full to empty in ~1.25 in-game days
 const STAMINA_REGEN := 24.0
 const STAMINA_DELAY := 1.0
 const WET_SECONDS := 90.0
+const REST_AFTER := 20.0       ## seconds sheltered by a fire before you're Rested
+const REST_SECONDS := 300.0    ## Rested: stamina regenerates 50% faster
 
 var health := MAX
 var stamina := MAX
@@ -28,6 +30,11 @@ var wet := 0.0               ## seconds of "Wet" left
 var heat := 0.0              ## 0..1 from nearby fires etc (last step)
 var statuses: Array[String] = []
 var dead := false
+var roofed := false          ## a roof overhead (rain can't reach you)
+var sheltered := false       ## roof and walls (the weather barely reaches you)
+var rested := 0.0            ## seconds of Rested left
+var _shelter_left := 0.0
+var _rest_build := 0.0
 
 var player: CharacterBody3D
 var world: Node3D
@@ -42,7 +49,23 @@ func step(dt: float) -> void:
 		return
 	var p := player.global_position
 	heat = world.heat_at(p)
-	var target: float = world.air_warmth(p) + heat * 70.0
+	_shelter_left -= dt
+	if _shelter_left <= 0.0:
+		_shelter_left = 0.25
+		roofed = world.build.roofed_at(p)
+		sheltered = roofed and world.build.enclosure_at(p) >= 0.74
+	# Rain soaks you unless there's a roof over your head.
+	if not roofed and world.weather.rain_at(p) > 0.25:
+		wet = WET_SECONDS
+	# Resting: a while by a fire with a roof and walls around you.
+	if sheltered and heat > 0.25:
+		_rest_build += dt
+		if _rest_build >= REST_AFTER:
+			rested = maxf(rested, REST_SECONDS)
+	else:
+		_rest_build = 0.0
+	rested = maxf(rested - dt, 0.0)
+	var target: float = world.air_warmth(p, sheltered) + heat * 70.0
 	if wet > 0.0:
 		target -= 22.0
 		wet = maxf(wet - dt * (3.0 if heat > 0.3 else 1.0), 0.0)   # fires dry you off
@@ -55,7 +78,7 @@ func step(dt: float) -> void:
 	if _stamina_wait > 0.0:
 		_stamina_wait -= dt
 	else:
-		stamina = minf(stamina + STAMINA_REGEN * dt, MAX)
+		stamina = minf(stamina + STAMINA_REGEN * (1.5 if rested > 0.0 else 1.0) * dt, MAX)
 
 	var dmg := 0.0
 	if hunger <= 0.0:
@@ -87,6 +110,10 @@ func _update_statuses() -> void:
 		statuses.append("Hungry")
 	if wet > 0.0:
 		statuses.append("Wet")
+	if sheltered:
+		statuses.append("Sheltered")
+	if rested > 0.0:
+		statuses.append("Rested")
 
 ## Spends stamina for an action. Returns false (and spends nothing) if you're
 ## too tired. Continuous costs (sprinting) pass `partial = true`.
@@ -105,6 +132,16 @@ func eat(food: Dictionary) -> void:
 func soak() -> void:
 	wet = WET_SECONDS
 
+## After a night's sleep: a little hungrier, dry, warm and rested.
+func after_sleep(seconds: float) -> void:
+	hunger = maxf(hunger - HUNGER_DRAIN * seconds * 0.3, 0.0)
+	wet = 0.0
+	warmth = maxf(warmth, 60.0)
+	stamina = MAX
+	rested = REST_SECONDS * 2.0
+	_update_statuses()
+	changed.emit()
+
 func reset_after_death() -> void:
 	dead = false
 	health = 50.0
@@ -115,7 +152,7 @@ func reset_after_death() -> void:
 	changed.emit()
 
 func to_data() -> Dictionary:
-	return {"health": health, "stamina": stamina, "hunger": hunger, "warmth": warmth, "wet": wet}
+	return {"health": health, "stamina": stamina, "hunger": hunger, "warmth": warmth, "wet": wet, "rested": rested}
 
 func load_data(d: Dictionary) -> void:
 	health = float(d.get("health", health))
@@ -123,5 +160,6 @@ func load_data(d: Dictionary) -> void:
 	hunger = float(d.get("hunger", hunger))
 	warmth = float(d.get("warmth", warmth))
 	wet = float(d.get("wet", 0.0))
+	rested = float(d.get("rested", 0.0))
 	dead = false
 	changed.emit()