Wolf den search steps into the valley when the rim is steep everywhere

scripts/creatures/den.gd

@@ -57,40 +57,53 @@ func _find_site(world: Node3D) -> Vector3:
 	var space := world.get_world_3d().direct_space_state
 	var box := BoxShape3D.new()
 	box.size = Vector3(HALF_SIZE * 2.0, 6.0, HALF_SIZE * 2.0)
-	var ex: Array[RID] = [terrain.get_node("TerrainBody").get_rid(), world.player.get_rid()]
-	for step in range(52):
-		var ang := deg_to_rad(start + step * 7.0)
-		var dir := Vector2(cos(ang), sin(ang))
-		# Walk inward from the rim until the den sits inside the walkable
-		# area, a little way short of the wall.
-		var r: float = terrain.play_radius + 10.0
-		while r > terrain.play_radius - 40.0:
-			var x := dir.x * r
-			var z := dir.y * r
-			if terrain.inside_boundary(x, z, 11.0):
-				break
-			r -= 1.0
-		var c := Vector3(dir.x * r, 0, dir.y * r)
-		if terrain.sea_weight(c.x, c.z) > 0.02 or Vector2(c.x, c.z).length() < 50.0:
-			continue
-		var hs: Array[float] = []
-		for d in [Vector2(-1, -1), Vector2(1, -1), Vector2(-1, 1), Vector2(1, 1), Vector2.ZERO]:
-			hs.append(terrain.sample_height(c.x + d.x * 4.0, c.z + d.y * 4.0))
-		if hs.max() - hs.min() > 2.2 or hs.min() < terrain.water_level + 1.0:
-			continue
-		c.y = hs[4]
-		# Trees and boulders in the way are cleared (_clear_area); just avoid
-		# the thickest woods. Counted by position, because their colliders
-		# were only just created and the physics space hasn't seen them yet.
-		var crowd := 0
-		for uid in world.props.resource_nodes:
-			var n: Node3D = world.props.resource_nodes[uid]
-			if Vector2(n.global_position.x - c.x, n.global_position.z - c.z).length() < HALF_SIZE:
-				crowd += 1
-		if crowd <= 5:
-			return c
+	# Pass 1 tries only the foot of the rim wall in each direction (the
+	# original search, so islands that already had a den keep it in the same
+	# place). Where the rim is steep all the way round (seed 777, seed 4),
+	# pass 2 steps further into the valley, a few metres at a time.
+	for pass_insets in [[0.0], [3.0, 6.0, 9.0, 12.0, 16.0, 20.0, 25.0, 30.0]]:
+		for step in range(52):
+			var ang := deg_to_rad(start + step * 7.0)
+			var dir := Vector2(cos(ang), sin(ang))
+			var r_foot := _rim_foot(dir)
+			for inset in pass_insets:
+				var c := _check_site(world, dir * (r_foot - inset))
+				if c != Vector3.INF:
+					return c
 	return Vector3.INF
 
+## Walks inward from the rim until the den sits inside the walkable area, a
+## little way short of the wall. Returns that distance from the centre.
+func _rim_foot(dir: Vector2) -> float:
+	var r: float = terrain.play_radius + 10.0
+	while r > terrain.play_radius - 40.0:
+		if terrain.inside_boundary(dir.x * r, dir.y * r, 11.0):
+			break
+		r -= 1.0
+	return r
+
+## The site at `p` (x, z) with its height, or INF if it's no good: near the
+## sea or the spawn, too sloped, too low, or in thick woods.
+func _check_site(world: Node3D, p: Vector2) -> Vector3:
+	if terrain.sea_weight(p.x, p.y) > 0.02 or p.length() < 50.0:
+		return Vector3.INF
+	var hs: Array[float] = []
+	for d in [Vector2(-1, -1), Vector2(1, -1), Vector2(-1, 1), Vector2(1, 1), Vector2.ZERO]:
+		hs.append(terrain.sample_height(p.x + d.x * 4.0, p.y + d.y * 4.0))
+	if hs.max() - hs.min() > 2.2 or hs.min() < terrain.water_level + 1.0:
+		return Vector3.INF
+	# Trees and boulders in the way are cleared (_clear_area); just avoid
+	# the thickest woods. Counted by position, because their colliders
+	# were only just created and the physics space hasn't seen them yet.
+	var crowd := 0
+	for uid in world.props.resource_nodes:
+		var n: Node3D = world.props.resource_nodes[uid]
+		if Vector2(n.global_position.x - p.x, n.global_position.z - p.y).length() < HALF_SIZE:
+			crowd += 1
+	if crowd > 5:
+		return Vector3.INF
+	return Vector3(p.x, hs[4], p.y)
+
 ## Removes the trees, boulders, bushes and pickups the den is built over.
 ## Deterministic (the site comes from the seed), and the other scenery keeps
 ## its save ids because those come from creation order.

tests/run_all.sh

@@ -9,7 +9,7 @@ if [ ! -f .godot/global_script_class_cache.cfg ]; then
 	echo "Importing the project first (fresh copy)..."
 	godot --headless --path . --import >/dev/null 2>&1
 fi
-for t in test_survival_core test_survival_stats test_save_load test_weather_building test_creatures_combat test_wolves test_fishing_diet test_net_lobby test_net_world test_terrain_edges test_boundary; do
+for t in test_survival_core test_survival_stats test_save_load test_weather_building test_creatures_combat test_wolves test_den_sites test_fishing_diet test_net_lobby test_net_world test_terrain_edges test_boundary; do
 	extra=""
 	[ "$t" = "test_boundary" ] && extra="--fixed-fps 30"
 	# A suite that waits on a world that failed to load would hang forever,

tests/test_den_sites.gd

@@ -0,0 +1,42 @@
+extends SceneTree
+## Every island gets a wolf den: across many seeds the site search finds a
+## spot away from the spawn and the sea.
+## Run: godot --headless --path . --script res://tests/test_den_sites.gd
+
+const SEEDS := [777, 4, 1337, 1, 2, 3, 5, 6, 7, 8, 9, 10, 42, 99, 123, 2024, 4242, 9001, 31337, 65535]
+
+var _fails := 0
+
+func check(cond: bool, what: String) -> void:
+	print(("  ok   " if cond else "  FAIL ") + what)
+	if not cond:
+		_fails += 1
+
+func _initialize() -> void:
+	_run.call_deferred()
+
+func _run() -> void:
+	var S: Node = root.get_node("Saves")
+	S.root_dir = "user://test_den_sites"
+	for seed in SEEDS:
+		for w in S.list_worlds():
+			S.delete_world(w.id)
+		S.current_id = S.create_world("Den %d" % seed, seed)
+		var world: Node3D = load("res://scenes/world.tscn").instantiate()
+		root.add_child(world)
+		for _i in range(3):
+			await physics_frame
+		var den: Node3D = world.den
+		var t: Node3D = world.terrain
+		var p: Vector3 = den.position
+		var ok: bool = den.found
+		if ok:
+			ok = Vector2(p.x, p.z).length() >= 50.0 and t.sea_weight(p.x, p.z) <= 0.02
+		check(ok, "seed %d has a den (%.0f m from the centre)" % [seed, Vector2(p.x, p.z).length()])
+		world.queue_free()
+		await physics_frame
+	for w in S.list_worlds():
+		S.delete_world(w.id)
+	DirAccess.remove_absolute(S.root_dir)
+	print("RESULT: %s (%d failures)" % ["PASS" if _fails == 0 else "FAIL", _fails])
+	quit(1 if _fails > 0 else 0)