Smooth boosted fleet travel

controllers/GameController.gd

@@ -103,6 +103,13 @@ var keyboard_steering: bool = false
 
 
 func _ready() -> void:
+	# Most visuals still animate per rendered frame. The main/surface scenes opt
+	# their roots out of global interpolation, then opt their physics-follow
+	# camera and Ship.tscn hulls back in.
+	# Running the camera after ordinary physics nodes lets it follow the ships'
+	# newest centroid, and interpolation fills the display frames in between.
+	process_physics_priority = 1
+	camera.reset_physics_interpolation()
 	# #148: the main theme, which outlives this scene - see Music.ensure().
 	# This script is the root of BOTH the space scene and the planet
 	# surface, so one call here covers the whole game.
@@ -292,7 +299,7 @@ func _process(delta: float) -> void:
 	_update_pivot(delta)
 
 	# Keep the heading fresh while a control is held. Fleet advances its own
-	# anchor in _process, so this only needs to report the direction. The
+	# anchor in _physics_process, so this only needs to report the direction. The
 	# keyboard takes precedence, and releasing the keys has to stop the fleet
 	# itself - unlike the stick, there is no centred-again signal to hook.
 	# #124: the breach drives. One check here covers the stick, the keyboard
@@ -303,6 +310,12 @@ func _process(delta: float) -> void:
 	else:
 		_apply_steering()
 
+
+func _physics_process(delta: float) -> void:
+	_update_camera(delta)
+
+
+func _update_camera(delta: float) -> void:
 	var target: Vector2 = fleet.get_centroid()
 	if camera.global_position.distance_to(target) <= camera_snap_distance:
 		# Snap and stop dead - see camera_snap_distance. Assigning the exact

core/GameState.gd

@@ -2634,12 +2634,24 @@ func _advance_resource_converters(delta: float) -> void:
 		building.conversion_progress = progress
 
 
-func _advance_distorder_drain(delta: float) -> void:
+func _distorder_boost_in_use() -> bool:
+	for fleet in get_tree().get_nodes_in_group("player_fleet"):
+		if fleet.has_method("is_using_speed_boost") and fleet.is_using_speed_boost():
+			return true
+	return false
+
+
+func _advance_distorder_drain(delta: float, boost_in_use: bool = true) -> void:
 	if fleet_speed_multiplier <= 1.0:
 		# Nothing owed at 1.0x - and no stale fractional progress should
 		# carry over into a LATER, unrelated boost.
 		_distorder_drain_progress = 0.0
 		return
+	if not boost_in_use:
+		# The fader is a selected cruise speed, not an always-running machine.
+		# Keep any already-earned fraction so stopping cannot erase a nearly
+		# complete unit of cost, but accrue nothing while the fleet is parked.
+		return
 	# Normalized against the CURRENT ceiling, so "full boost" always costs
 	# ENERGY_DRAIN_PER_SECOND however many distorder vessels widened it -
 	# a bigger fleet buys more speed, not cheaper speed.
@@ -2897,7 +2909,7 @@ func _process(delta: float) -> void:
 	_advance_planning()
 	_advance_repairs(delta)
 	_advance_resource_converters(delta)
-	_advance_distorder_drain(delta)
+	_advance_distorder_drain(delta, _distorder_boost_in_use())
 	_advance_quests()
 	for e in extractors:
 		e.mining_progress = float(e.get("mining_progress", 0.0)) + delta * EXTRACTOR_RATE

project.godot

@@ -36,6 +36,10 @@ theme/default_font_size=78
 
 pointing/emulate_mouse_from_touch=false
 
+[physics]
+
+common/physics_interpolation=true
+
 [rendering]
 
 renderer/rendering_method="gl_compatibility"

surface/PlanetSetupEditor.tscn

@@ -5,6 +5,7 @@
 [ext_resource type="Script" path="res://ui/IconButton.gd" id="4"]
 
 [node name="PlanetSetupEditor" type="Node2D"]
+physics_interpolation_mode = 2
 script = ExtResource("1")
 
 [node name="BackgroundLayer" parent="." instance=ExtResource("3")]

surface/PlanetSurface.tscn

@@ -19,6 +19,7 @@
 [ext_resource type="Script" path="res://ui/QuestPanel.gd" id="quest_panel"]
 
 [node name="PlanetSurface" type="Node2D"]
+physics_interpolation_mode = 2
 script = ExtResource("1")
 
 [node name="BackgroundLayer" parent="." instance=ExtResource("3")]
@@ -47,8 +48,11 @@ script = ExtResource("dash_ctrl")
 script = ExtResource("ability_layout")
 
 [node name="Camera2D" type="Camera2D" parent="."]
+process_physics_priority = 2
+physics_interpolation_mode = 1
 position = Vector2(0, 0)
 zoom = Vector2(1, 1)
+process_callback = 0
 
 [node name="SurfaceFeatures" type="Node2D" parent="."]
 

tests/test_distorder_energy.gd

@@ -113,11 +113,45 @@ func _process(delta: float) -> bool:
 			root.add_child(main)
 			fleet = main.get_node("Fleet")
 			fader = main.get_node("UI/SpeedFader")
-			fleet.spawn_ships(1, Vector2.ZERO, PackedStringArray([GameState.VESSEL_DISTORDER]))
+			# A carrier supplies the hold the Propulser burns from. The previous
+			# one-Propulser fixture had zero cargo capacity, so its depletion check
+			# accidentally began with no energy regardless of what it deposited.
+			fleet.spawn_ships(2, Vector2.ZERO, PackedStringArray([
+				GameState.VESSEL_CARRIER, GameState.VESSEL_DISTORDER]))
 			fader._process(0.0)
 			if not fader.visible:
 				return _fail_now("fader hidden with a distorder ship in the fleet")
+			if not bool(ProjectSettings.get_setting(
+					"physics/common/physics_interpolation", false)):
+				return _fail_now("physics interpolation is disabled for boosted flight")
+			if fleet.ships[0].physics_interpolation_mode \
+					!= Node.PHYSICS_INTERPOLATION_MODE_ON:
+				return _fail_now("the boosted vessel is not physics-interpolated")
+			if main.get_node("Camera2D").physics_interpolation_mode \
+					!= Node.PHYSICS_INTERPOLATION_MODE_ON:
+				return _fail_now("the fleet camera is not physics-interpolated")
 
+			# #199: choosing a higher cruise speed is free while parked. Once a
+			# heading is active, the exact same multiplier resumes its normal drain.
+			game_state.deposit_fleet_resource(GameState.RESOURCE_ENERGY, 30)
+			game_state.set_fleet_speed_multiplier(GameState.MAX_FLEET_SPEED_MULTIPLIER)
+			var parked_energy: int = game_state.fleet_resource(GameState.RESOURCE_ENERGY)
+			game_state._advance_distorder_drain(5.0,
+				game_state._distorder_boost_in_use())
+			if game_state.fleet_resource(GameState.RESOURCE_ENERGY) != parked_energy:
+				return _fail_now("a parked fleet consumed boost energy")
+			fleet.move_in_direction(Vector2.RIGHT)
+			if not fleet.is_using_speed_boost():
+				return _fail_now("boosted cruise did not report its energy use")
+			game_state._advance_distorder_drain(1.0,
+				game_state._distorder_boost_in_use())
+			if game_state.fleet_resource(GameState.RESOURCE_ENERGY) >= parked_energy:
+				return _fail_now("moving at boosted cruise consumed no energy")
+			fleet.stop()
+			print("parked boost was free; moving boost resumed drain")
+
+			game_state.withdraw_fleet_resource(GameState.RESOURCE_ENERGY,
+				game_state.fleet_resource(GameState.RESOURCE_ENERGY))
 			game_state.deposit_fleet_resource(GameState.RESOURCE_ENERGY, 4)
 			game_state.set_fleet_speed_multiplier(GameState.MAX_FLEET_SPEED_MULTIPLIER)
 			fader._process(0.0)

tests/test_energy_propulser_dash.gd

@@ -67,14 +67,14 @@ func _process(delta: float) -> bool:
 				return _fail("the Propulser that dashed did not enter cooldown")
 			# The burst should cover substantially more than a linear quarter of
 			# its distance at a quarter of its duration, then ease into its stop.
-			fleet.set_process(false)
+			fleet.set_physics_process(false)
 			fleet._advance_dash(fleet.dash_duration * 0.25)
 			var early_distance: float = fleet.get_centroid().distance_to(first_origin)
 			if early_distance <= DASH_DISTANCE * 0.45 \
 					or early_distance >= DASH_DISTANCE * 0.7:
 				return _fail("dash has no useful ease-out curve (quarter-time distance %.1f)" \
 					% early_distance)
-			fleet.set_process(true)
+			fleet.set_physics_process(true)
 			dash._process(0.0)
 			if not main.get_node("UI/DashButton").enabled:
 				return _fail("one cooling Propulser disabled a second ready one")

ui/MainMenu.tscn

@@ -4,6 +4,7 @@
 [ext_resource type="Script" uid="uid://dcvdmc68b3nve" path="res://ui/IconButton.gd" id="2"]
 
 [node name="MainMenu" type="Node2D" unique_id=2119550059]
+physics_interpolation_mode = 2
 script = ExtResource("1")
 
 [node name="BackgroundLayer" type="CanvasLayer" parent="." unique_id=1572211077]

vessels/Fleet.gd

@@ -230,6 +230,7 @@ func teleport_to(world_pos: Vector2) -> void:
 		ship.move_target += displacement
 		ship.velocity = Vector2.ZERO
 		ship.fleet_velocity = Vector2.ZERO
+		ship.reset_physics_interpolation()
 	steer_direction = Vector2.ZERO
 	dash_remaining = 0.0
 	dash_direction = Vector2.ZERO
@@ -242,7 +243,7 @@ func teleport_to(world_pos: Vector2) -> void:
 
 
 func move_in_direction(direction: Vector2) -> void:
-	# Joystick steering. Sets the heading; _process advances the anchor.
+	# Joystick steering. Sets the heading; _physics_process advances the anchor.
 	#
 	# This used to park a target 2000 units ahead and let the ships chase
 	# it. That made formation changes barely register while flying: with
@@ -275,7 +276,13 @@ func is_dashing() -> bool:
 	return dash_remaining > 0.0
 
 
-func _process(delta: float) -> void:
+func is_using_speed_boost() -> bool:
+	return GameState.fleet_speed_multiplier > 1.0 \
+		and steer_direction != Vector2.ZERO and not is_dashing() \
+		and not ships.is_empty()
+
+
+func _physics_process(delta: float) -> void:
 	# #158: a building may pay a local cost out of the hold when the fleet is
 	# actually standing at it, and the autoload has no other way to know
 	# where that is. Written before the early return below - a parked fleet

vessels/Ship.tscn

@@ -6,6 +6,7 @@
 radius = 16.0
 
 [node name="Ship" type="Area2D"]
+physics_interpolation_mode = 1
 script = ExtResource("1")
 
 [node name="CollisionShape2D" type="CollisionShape2D" parent="."]

world/IntroDirector.gd

@@ -485,6 +485,7 @@ func _complete_whiteout() -> void:
 	whiteout_teleported = true
 	fleet.teleport_to(DEFAULT_SPAWN)
 	camera.global_position = fleet.get_centroid()
+	camera.reset_physics_interpolation()
 	camera.offset = Vector2.ZERO
 
 

world/Main.tscn

@@ -57,6 +57,7 @@ shader_parameter/cell_size = 60.0
 shader_parameter/bg_color = Color(0.02, 0.02, 0.08, 1)
 
 [node name="Main" type="Node2D"]
+physics_interpolation_mode = 2
 script = ExtResource("3")
 
 [node name="BackgroundLayer" type="CanvasLayer" parent="."]
@@ -94,8 +95,11 @@ script = ExtResource("dash_ctrl")
 script = ExtResource("ability_layout")
 
 [node name="Camera2D" type="Camera2D" parent="."]
+process_physics_priority = 2
+physics_interpolation_mode = 1
 position = Vector2(0, 0)
 zoom = Vector2(1, 1)
+process_callback = 0
 
 [node name="EnemySpawner" type="Node2D" parent="."]
 script = ExtResource("4")