Generate complete freshwater and elevated terrain features

tests/fishing_surface_validation.gd

@@ -199,6 +199,59 @@ func _validate_portable_water_body() -> void:
 	mesh_derived_body.queue_free()
 	await process_frame
 
+	var polygon_body := WaterBodyScene.instantiate() as WaterBodyAuthoring
+	polygon_body.position = Vector3(30.0, 5.0, 20.0)
+	polygon_body.surface_polygon = PackedVector2Array([
+		Vector2(-4.0, -4.0),
+		Vector2(4.0, -4.0),
+		Vector2(4.0, 4.0),
+		Vector2(0.0, 1.0),
+		Vector2(-4.0, 4.0),
+	])
+	polygon_body.visual_surface_enabled = false
+	polygon_body.fish_pool = PondPool
+	root.add_child(polygon_body)
+	await physics_frame
+	await physics_frame
+
+	var polygon_fishing_region := polygon_body.get_node(
+		"FishingRegion"
+	) as FishableWaterRegionType
+	var polygon_recovery_region := polygon_body.get_node(
+		"RecoveryRegion"
+	) as Area3D
+	assert(polygon_fishing_region.get_child_count() == 3)
+	assert(polygon_recovery_region.get_child_count() == 3)
+	for child: Node in polygon_fishing_region.get_children():
+		var polygon_shape_node := child as CollisionShape3D
+		assert(polygon_shape_node != null)
+		assert(polygon_shape_node.shape is ConvexPolygonShape3D)
+
+	var polygon_resolver := FishingSurfaceResolverType.new()
+	var polygon_space_state := (
+		polygon_body.get_world_3d().direct_space_state
+	)
+	var polygon_inside: FishingSurfaceSampleType = (
+		polygon_resolver.resolve_surface(
+			polygon_space_state,
+			Vector3(30.0, 0.0, 20.0),
+			8.0,
+		)
+	)
+	assert(polygon_inside.is_fishable())
+	assert(is_equal_approx(polygon_inside.position.y, 5.0))
+	var polygon_notch: FishingSurfaceSampleType = (
+		polygon_resolver.resolve_surface(
+			polygon_space_state,
+			Vector3(30.0, 0.0, 23.0),
+			8.0,
+		)
+	)
+	assert(not polygon_notch.has_surface)
+
+	polygon_body.queue_free()
+	await process_frame
+
 
 func _validate_starter_region_surfaces() -> void:
 	var region := StarterRegionScene.instantiate() as Node3D