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.