Implement #77, #78 and #79

#77 - the Distorder becomes the Energy Propulser. Renamed everywhere the
player reads it, reskinned to match: a symmetric hull flaring into an engine
skirt instead of the lopsided warped lump, an engine bell with a thrust plume
instead of the wobbling ring glyph, and energy's own yellow instead of purple,
since energy is what it burns. The internal id stays "distorder" - it is the
capability string, the unlock key and the component scene name, and renaming
the wiring would be a large mechanical change with no player-visible effect.

Its speed ceiling now grows with the LOGARITHM of how many fly. Each one used
to add a flat 1.0, so a fleet that could afford six simply drove at six times
cruise and the vessel stopped being a choice. Base-2 makes the rule one
sentence - every doubling adds another 1.0 - and leaves two propulsers worth
exactly what they were worth before, so nothing already built is devalued.

#78 - a gas burner can be paused. It converts gas the player may want for
bombs into energy they may not need yet, and the only way to stop it was to
demolish it. The action is data-driven like every other: the visual's
ActionProvider lists "pause", and any converter can adopt it. Pause is the
burner's PRIMARY action, so it is one tap rather than a menu; the button shows
what it will DO, bars while running and a play triangle while stopped; and the
building itself goes visibly cold, because a paused building that looked
identical to a running one would be a setting to remember rather than see.
Conversion progress is left where it was rather than reset, so switching off
and on again does not discard a part-finished unit.

#79 - picking something up says so. A "+N" with the resource's own mark rises
and fades where it happened. Built from the SAME glyph the resource tables and
transfer rows use, so a material added to the catalog later cannot end up with
one mark in the HUD and a different one in the world. A pickup a full hold
REFUSES raises nothing.

Two Godot traps cost real time here and are now written down where the next
person will hit them:

  - a `#` comment inside a .tres [resource] block is not a comment. It parses
    as part of the preceding value and silently blanks the property after it.
    One in DistorderVesselDefinition.tres left definition_id empty, which
    surfaced as "<blank> did not resolve its definition" in a test far from
    the edit. The note lives in VesselDefinition.gd now.
  - a global class_name is not reliably resolvable, INCLUDING a script's own
    inside its own static function. ResourcePickupVFX.new() failed to compile
    when reached through a preview scene, taking Rock and the gas vents with
    it. It has no class_name now and constructs itself by path.

Suite 114/114.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

BuildController.gd

@@ -432,7 +432,7 @@ func _process(delta: float) -> void:
 	var actions: Array = _context_action_buttons()
 	action_button.visible = not actions.is_empty()
 	if current_building != null:
-		building_action_button.icon = int(current_building.definition.action_icon)
+		building_action_button.icon = _building_action_icon(current_building)
 		building_action_button.queue_redraw()
 	if not actions.is_empty():
 		action_button.icon = int(actions[0].icon) if actions.size() == 1 else IconButton.Icon.ACTION_MENU
@@ -489,6 +489,16 @@ func _has_transfer_context() -> bool:
 	return current_building != null and current_building.available_actions().has("transfer")
 
 
+# A pause action's icon shows what the button will DO, not what the building
+# currently is: two bars while it runs, a play triangle while it is stopped.
+# Everything else uses the icon its definition names.
+func _building_action_icon(building: Node) -> int:
+	if building.primary_action() == "pause":
+		return IconButton.Icon.RESUME if GameState.is_building_paused(building.building_id) \
+			else IconButton.Icon.PAUSE
+	return int(building.definition.action_icon)
+
+
 func _button_for_building_action(action: String) -> IconButton:
 	if action == "transfer":
 		return null
@@ -540,6 +550,15 @@ func _on_action_pressed() -> void:
 		bar.building_id = current_building.building_id
 
 	var action: String = current_building.primary_action()
+	if action == "pause":
+		# No panel: the button IS the control. Toggling here rather than
+		# opening something keeps a one-bit setting to a single tap.
+		var paused: bool = GameState.toggle_building_paused(current_building.building_id)
+		build_status.text = "%s %s" % [current_building.definition.display_name,
+			"paused" if paused else "running"]
+		building_action_button.icon = _building_action_icon(current_building)
+		building_action_button.queue_redraw()
+		return
 	if action == "research":
 		skill_menu.visible = true
 		skill_tree.reset_scroll()

BuildingVisualBase.gd

@@ -294,14 +294,20 @@ const BURNER_VENT_LENGTH: float = 26.0
 const BURNER_PORT_RADIUS: float = 6.0
 
 
-func _draw_gas_burner_static(target: CanvasItem) -> void:
+# `cold` draws the burner switched off (#78): the structure is still there,
-	var c: Color = GAS_BURNER_COLOR
+# but the fire in the middle is out and the output ports are dark. A paused
+# building that looked identical to a running one would be a setting the
+# player has to remember rather than see.
+func _draw_gas_burner_static(target: CanvasItem, cold: bool = false) -> void:
+	var c: Color = GAS_BURNER_COLOR.darkened(0.55) if cold else GAS_BURNER_COLOR
 
-	NeonDraw.draw_glowing_polygon(target, _ring(Vector2.ZERO, BURNER_CHAMBER_RADIUS, 6, PI / 6.0), c, 1.0)
+	NeonDraw.draw_glowing_polygon(target, _ring(Vector2.ZERO, BURNER_CHAMBER_RADIUS, 6, PI / 6.0), c,
+		0.55 if cold else 1.0)
 	NeonDraw.draw_glowing_polygon(target, _ring(Vector2.ZERO, BURNER_CORE_RADIUS, 6, PI / 6.0), c, 0.5,
 		NeonDraw.DEFAULT_CORE, 0.7)
-	NeonDraw.draw_glowing_polygon(target, _ring(Vector2.ZERO, BURNER_CORE_RADIUS * 0.5, 6, PI / 6.0),
+	if not cold:
-		Color(1.0, 0.75, 0.35), 0.85)
+		NeonDraw.draw_glowing_polygon(target, _ring(Vector2.ZERO, BURNER_CORE_RADIUS * 0.5, 6, PI / 6.0),
+			Color(1.0, 0.75, 0.35), 0.85)
 
 	for i in range(BURNER_VENT_COUNT):
 		var a: float = (float(i) / BURNER_VENT_COUNT) * TAU + PI / 4.0
@@ -310,10 +316,12 @@ func _draw_gas_burner_static(target: CanvasItem) -> void:
 		# Intake vent in gas's own colour, so it is unmistakably the feed
 		# rather than another structural brace.
 		NeonDraw.draw_glowing_line(target, dir * BURNER_CHAMBER_RADIUS, tip,
-			Color(0.85, 0.52, 1.0), 0.7, 0.34)
+			Color(0.85, 0.52, 1.0), 0.25 if cold else 0.7, 0.34)
 		# Output port glowing in energy's colour, at the same vent tip -
 		# the building's own silhouette shows both ends of the conversion.
-		NeonDraw.draw_glowing_polygon(target, _ring(tip, BURNER_PORT_RADIUS, 5), GAS_BURNER_ENERGY_COLOR, 0.9)
+		NeonDraw.draw_glowing_polygon(target, _ring(tip, BURNER_PORT_RADIUS, 5),
+			GAS_BURNER_ENERGY_COLOR.darkened(0.6) if cold else GAS_BURNER_ENERGY_COLOR,
+			0.3 if cold else 0.9)
 
 
 func _diamond(centre: Vector2, r: float) -> PackedVector2Array:

DistorderVesselDefinition.tres

@@ -4,21 +4,21 @@
 [resource]
 script = ExtResource("1")
 definition_id = "distorder"
-display_name = "Distorder"
+display_name = "Energy Propulser"
-description = "Unarmed space-time distortion hull. While one flies with the fleet, a fader lets you push cruise speed beyond its default."
+description = "Unarmed propulsion hull that burns energy to drive the whole fleet faster. While one flies with you, a fader lets you push cruise speed past its default."
 build_cost = 14
 build_resource_costs = {"ore": 14, "energy": 8}
 build_time = 16.0
 icon = 37
-glow_color = Color(0.7, 0.3, 1, 1)
+glow_color = Color(0.85, 0.95, 0.15, 1)
-hull_points = PackedVector2Array(0, -24, -14, -2, -6, 18, 10, 10, 12, -10)
+hull_points = PackedVector2Array(0, -26, 9, -8, 13, 6, 18, 20, 0, 12, -18, 20, -13, 6, -9, -8)
 fleet_eligible = true
 capabilities = PackedStringArray("distorder")
 component_scenes = Array[PackedScene]([ExtResource("2")])
 base_stats = {"max_speed": 430.0, "acceleration": 1230.0, "delivery_speed": 180.0}
 unlock_id = "unlock_distorder"
-unlock_name = "Unlock Distorder"
+unlock_name = "Unlock Energy Propulser"
-unlock_description = "Research a space-time distortion hull - while one flies with the fleet, a fader lets you push cruise speed beyond its default."
+unlock_description = "Research a propulsion hull that burns energy to drive the whole fleet faster - while one flies with you, a fader lets you push cruise speed past its default."
 unlock_cost = 0
 unlock_resource_costs = {"energy": 50}
 research_point_cost = 1

GameState.gd

@@ -31,8 +31,8 @@ var planet_definition_id: String = "rocky"
 # anchor, Ship's own max_speed/acceleration) rather than baked into stored
 # stats, so a speed upgrade researched while boosted can't corrupt the base
 # value - see Fleet.gd/Ship.gd for the multiply sites.
-# The ceiling ONE distorder vessel reaches. Each ADDITIONAL one raises it by
+# The ceiling ONE Energy Propulser reaches. Every DOUBLING of them raises it
-# another 1.0 - see set_distorder_vessel_count(). Kept as the one-vessel
+# by another 1.0 - see set_distorder_vessel_count(). Kept as the one-vessel
 # figure rather than an absolute cap so the fader's meaning at a single
 # vessel is unchanged.
 const MAX_FLEET_SPEED_MULTIPLIER: float = 3.0
@@ -67,8 +67,23 @@ func set_fleet_speed_multiplier(value: float) -> void:
 # Re-clamps the CURRENT multiplier, so losing a distorder vessel mid-boost
 # pulls the fleet down to the new ceiling instead of leaving it travelling
 # faster than its remaining crew can sustain.
+# #77: the ceiling grows with the LOGARITHM of how many propulsers fly, not
+# linearly. Each one used to add a flat 1.0, so a fleet that could afford six
+# of them simply drove at six times cruise and the vessel stopped being a
+# choice. Base-2, which makes the rule one sentence: every DOUBLING of
+# propulsers buys another 1.0.
+#
+#   1 -> 3.0    2 -> 4.0    4 -> 5.0    8 -> 6.0
+#
+# Two propulsers are worth exactly what they were worth before, so nothing a
+# player has already built is devalued; it is the fifth and sixth that stop
+# paying for themselves.
 func set_distorder_vessel_count(count: int) -> void:
-	max_fleet_speed_multiplier = MAX_FLEET_SPEED_MULTIPLIER + maxf(float(count) - 1.0, 0.0)
+	if count <= 1:
+		max_fleet_speed_multiplier = MAX_FLEET_SPEED_MULTIPLIER
+		return
+	max_fleet_speed_multiplier = MAX_FLEET_SPEED_MULTIPLIER \
+		+ log(float(count)) / log(2.0)
 	set_fleet_speed_multiplier(fleet_speed_multiplier)
 
 
@@ -1337,6 +1352,31 @@ func _collectable_building_resource(building: Dictionary, minimum_amount: int) -
 	return ""
 
 
+# #78: a converter can be switched off. A gas burner turns gas the player may
+# want for bombs into energy they may not need yet, and until now it did that
+# relentlessly - the only way to stop it was to demolish it. Paused is stored
+# on the building record like every other piece of its state.
+func is_building_paused(id: int) -> bool:
+	return bool(find_building(id).get("paused", false))
+
+
+func set_building_paused(id: int, paused: bool) -> void:
+	var building: Dictionary = find_building(id)
+	if building.is_empty():
+		return
+	building.paused = paused
+	building_paused_changed.emit(id, paused)
+
+
+func toggle_building_paused(id: int) -> bool:
+	var paused: bool = not is_building_paused(id)
+	set_building_paused(id, paused)
+	return paused
+
+
+signal building_paused_changed(id: int, paused: bool)
+
+
 func _advance_resource_converters(delta: float) -> void:
 	for building in buildings:
 		var profile: Resource = building_logistics_profile(building)
@@ -1344,6 +1384,11 @@ func _advance_resource_converters(delta: float) -> void:
 				or profile.conversion_output == "" or profile.conversion_rate <= 0.0 \
 				or profile.conversion_yield <= 0:
 			continue
+		if bool(building.get("paused", false)):
+			# Progress is left exactly where it was rather than reset, so
+			# switching a burner off and on again does not throw away the
+			# fraction of a unit it had already worked through.
+			continue
 		var inventory: RefCounted = _inventory_for_record(building)
 		if inventory.amount(profile.conversion_input) <= 0:
 			continue

GasBurnerBuildingVisual.gd

@@ -1,9 +1,45 @@
 extends "res://BuildingVisualBase.gd"
 
+# Drawn once, not per frame - the burner has no animation. It does have two
+# LOOKS though (#78): lit while it is converting, cold while the player has
+# paused it. A one-shot draw plus a redraw on the state signal keeps that free.
+#
+# GameState is reached through the tree rather than by its global autoload
+# name. This script is compiled as part of a preload chain from
+# BuildingDefinitions, which can happen before autoloads are registered - a
+# bare `GameState` reference here failed to compile outright, taking the whole
+# visual with it. Same hazard PlanetSetups and PlanetSurfaceController already
+# work around, and the same fix.
+
+
+func _state() -> Node:
+	return get_tree().root.get_node_or_null("GameState")
+
+
 func _ready() -> void:
 	set_process(false)
+	var state: Node = _state()
+	if state != null:
+		state.building_paused_changed.connect(_on_building_paused_changed)
 	queue_redraw()
 
+
+func _on_building_paused_changed(id: int, _paused: bool) -> void:
+	if id == _own_building_id():
+		queue_redraw()
+
+
+# The visual sits under Building/VisualHost, so its owner is two levels up.
+# Asked for rather than stored, because the visual is instantiated before the
+# Building node has finished setting its own id.
+func _own_building_id() -> int:
+	var host: Node = get_parent()
+	var building: Node = host.get_parent() if host != null else null
+	return int(building.building_id) if building != null and "building_id" in building else 0
+
+
 func _draw() -> void:
 	register_draw()
-	_draw_gas_burner_static(self)
+	var state: Node = _state()
+	var paused: bool = state != null and state.is_building_paused(_own_building_id())
+	_draw_gas_burner_static(self, paused)

GasBurnerBuildingVisual.tscn

@@ -8,4 +8,4 @@ script = ExtResource("1")
 
 [node name="ActionProvider" type="Node" parent="."]
 script = ExtResource("2")
-actions = PackedStringArray("transfer")
+actions = PackedStringArray("pause", "transfer")

GasVentField.gd

@@ -1,4 +1,12 @@
 extends Node2D
+
+# By path, not by its `ResourcePickupVFX` global name: a bare class-name
+# reference needs the global class cache already warm, which it is not when
+# this script is reached indirectly - loading Main.tscn from inside a preview
+# scene made it a hard parse error. Same workaround PlanetSetups and
+# PlanetSetupEditor already use.
+const RESOURCE_PICKUP_VFX = preload("res://ResourcePickupVFX.gd")
+
 @export var fleet_path: NodePath = NodePath("../Fleet")
 @onready var fleet: Node2D = get_node(fleet_path)
 var vents: Array[Vector2] = []
@@ -20,7 +28,10 @@ func _process(delta: float) -> void:
 				# undelivered whole units in progress rather than discarding
 				# them, so gas is only ever lost by not gathering it.
 				var whole: int = int(progress)
-				progress -= float(GameState.collect_gas_cargo(whole))
+				var taken: int = GameState.collect_gas_cargo(whole)
+				progress -= float(taken)
+				RESOURCE_PICKUP_VFX.spawn(get_tree().root,
+					to_global(vent), GameState.RESOURCE_GAS, taken)
 			return
 	progress = 0.0
 func _draw() -> void:

IconButton.gd

@@ -41,8 +41,15 @@ enum Icon {
 	# #58: LASER_VESSEL is the ship glyph, LASER_SHOT the action button -
 	# same two-icon split as GAS_BOMBER/GAS_BOMB above.
 	LASER_VESSEL, LASER_SHOT,
-	# #59: a warped ring reads as a space-time distortion rather than a hull.
+	# #59 drew this as a warped ring, for a vessel then called a space-time
+	# distorder. #77 renamed it the Energy Propulser and the glyph is now an
+	# engine bell; the enum name stays put because renumbering it would
+	# silently renumber every icon int stored in every scene.
 	DISTORDER_VESSEL,
+	# #78: switching a converter off and on. Appended, like everything above -
+	# inserting anywhere earlier renumbers every icon int already stored in a
+	# scene file.
+	PAUSE, RESUME,
 }
 
 # Size the glyphs were originally drawn against. Every glyph dimension is
@@ -272,6 +279,10 @@ func _draw() -> void:
 			_draw_gas_bomb(center, pulse, s)
 		Icon.GAS_BURNER:
 			_draw_gas_burner_icon(center, pulse, s)
+		Icon.PAUSE:
+			_draw_pause(center, pulse, s)
+		Icon.RESUME:
+			_draw_resume(center, pulse, s)
 		Icon.CARRIER_VESSEL:
 			_draw_carrier(center, pulse, s)
 		Icon.LASER_VESSEL:
@@ -319,15 +330,27 @@ func _draw_carrier(center: Vector2, pulse: float, s: float) -> void:
 
 
 func _draw_distorder_vessel(center: Vector2, pulse: float, s: float) -> void:
-	# A ring whose radius wobbles with angle instead of a plain circle -
+	# #77: an engine bell with a thrust plume under it. The glyph used to be a
-	# reads as warped space rather than a hull silhouette.
+	# ring with a wobbling radius, which read as warped space - correct for a
-	var points: PackedVector2Array = PackedVector2Array()
+	# "space-time distorder" and wrong for the Energy Propulser it now is.
-	for i in range(17):
+	var hull: PackedVector2Array = PackedVector2Array([
-		var a: float = TAU * float(i) / 16.0
+		center + Vector2(0.0, -13.0) * s,
-		var r: float = (10.0 + 3.0 * sin(a * 3.0)) * s
+		center + Vector2(5.0, -4.0) * s,
-		points.append(center + Vector2(cos(a), sin(a)) * r)
+		center + Vector2(7.0, 3.0) * s,
-	NeonDraw.draw_glowing_path(self, points, _active_color(), pulse, 0.8, core_color)
+		center + Vector2(10.0, 10.0) * s,
-	NeonDraw.draw_glowing_circle(self, center, 2.5 * s, _active_color(), pulse, core_color)
+		center + Vector2(-10.0, 10.0) * s,
+		center + Vector2(-7.0, 3.0) * s,
+		center + Vector2(-5.0, -4.0) * s,
+	])
+	NeonDraw.draw_glowing_polygon(self, hull, _active_color(), pulse, core_color)
+	# Three exhaust strokes, the middle one longest, so the thrust reads as
+	# coming OUT of the bell rather than as decoration beside it.
+	for offset in [-5.0, 0.0, 5.0]:
+		var length: float = 16.0 if is_zero_approx(offset) else 12.0
+		NeonDraw.draw_glowing_line(self,
+			center + Vector2(offset, 11.0) * s,
+			center + Vector2(offset, length) * s,
+			_active_color(), pulse * 0.8, 0.5, core_color)
 
 
 func _draw_laser_vessel(center: Vector2, pulse: float, s: float) -> void:
@@ -409,6 +432,25 @@ func _draw_horizontal_arrow(center: Vector2, pulse: float, direction: float, s:
 	NeonDraw.draw_glowing_line(self, tip, tip + Vector2(-r * 0.8 * direction, r * 0.7), _active_color(), pulse, 0.5 * s, core_color)
 
 
+func _draw_pause(center: Vector2, pulse: float, s: float) -> void:
+	# Two upright bars. Shown while something is RUNNING, because that is the
+	# action the button performs, not the state it is in.
+	for side in [-1.0, 1.0]:
+		var x: float = 5.0 * side * s
+		NeonDraw.draw_glowing_line(self, center + Vector2(x, -11.0 * s),
+			center + Vector2(x, 11.0 * s), _active_color(), pulse, 0.9, core_color)
+
+
+func _draw_resume(center: Vector2, pulse: float, s: float) -> void:
+	# A play triangle, shown while something is stopped.
+	var play: PackedVector2Array = PackedVector2Array([
+		center + Vector2(-7.0, -11.0) * s,
+		center + Vector2(11.0, 0.0) * s,
+		center + Vector2(-7.0, 11.0) * s,
+	])
+	NeonDraw.draw_glowing_polygon(self, play, _active_color(), pulse, core_color)
+
+
 func _draw_minus(center: Vector2, pulse: float, s: float) -> void:
 	var r: float = 9.0 * s
 	NeonDraw.draw_glowing_line(self, center + Vector2(-r, 0.0), center + Vector2(r, 0.0),

ResourcePickupVFX.gd

@@ -0,0 +1,101 @@
+extends Node2D
+
+# Forgejo #79: a small "+N" with the resource's own mark, rising and fading
+# where the fleet picked something up.
+#
+# Collecting used to be entirely silent - a rock vanished and a number in the
+# corner of the screen changed. Which number, and by how much, was left for
+# the player to notice on their own. This says it at the point it happened,
+# in the resource's own colour, and gets out of the way.
+#
+# Built from the SAME glyph scene the resource tables and transfer rows use
+# (ResourceDefinition.glyph_scene), so a new material added to the catalog
+# gets a correct pickup mark with no work here - and can never end up with
+# one mark in the HUD and a different one in the world.
+
+const RESOURCE_DEFINITIONS = preload("res://ResourceDefinitions.gd")
+# Deliberately NO class_name, and the constructor below loads this file by
+# path rather than naming the class. A global class-name identifier - even a
+# script's own, inside its own static function - needs the class cache already
+# warm, and it is not when this is reached indirectly through a preview scene
+# loading Main.tscn. That failed to compile outright, taking Rock and the gas
+# vents down with it. Callers preload the path too; see Rock.gd.
+const SELF_PATH: String = "res://ResourcePickupVFX.gd"
+
+const RISE_DISTANCE: float = 46.0
+const DURATION: float = 0.85
+const GLYPH_SIZE: float = 22.0
+const DIGIT_HEIGHT: float = 20.0
+# Held fully opaque for the first part of its life, so the eye has time to
+# catch it before it starts going.
+const FADE_START: float = 0.45
+
+var age: float = 0.0
+var colour: Color = Color.WHITE
+var start_y: float = 0.0
+
+
+static func spawn(parent: Node, world_position: Vector2, resource_type: String,
+		amount: int) -> void:
+	if amount <= 0:
+		return
+	var vfx: Node2D = (load(SELF_PATH) as GDScript).new()
+	vfx.position = world_position
+	vfx.build(resource_type, amount)
+	parent.add_child(vfx)
+
+
+func build(resource_type: String, amount: int) -> void:
+	var definition: Resource = RESOURCE_DEFINITIONS.get_definition(resource_type)
+	colour = definition.color if definition != null else Color.WHITE
+
+	if definition != null and definition.glyph_scene != null:
+		var glyph: Control = definition.glyph_scene.instantiate()
+		glyph.colour = definition.color
+		# Anchors first. The glyph scenes are authored as full-rect Controls
+		# for the panels that host them, and Godot recomputes the size of any
+		# Control with non-equal opposite anchors right after _ready() - so
+		# assigning size without this is overwritten, with a warning, the
+		# moment it enters the tree.
+		glyph.set_anchors_preset(Control.PRESET_TOP_LEFT)
+		glyph.size = Vector2(GLYPH_SIZE, GLYPH_SIZE)
+		glyph.position = Vector2(-2.0, -GLYPH_SIZE * 0.5)
+		add_child(glyph)
+
+	# show_icon off: the resource's own glyph is already beside it, and
+	# NeonNumber's built-in mark is the ore hexagon whatever the amount is.
+	var number := NeonNumber.new()
+	number.show_icon = false
+	number.amount = amount
+	number.digit_height = DIGIT_HEIGHT
+	number.glow_color = colour
+	number.core_color = colour.darkened(0.8)
+	number.size = Vector2(60.0, DIGIT_HEIGHT)
+	number.position = Vector2(GLYPH_SIZE + 4.0, -DIGIT_HEIGHT * 0.5)
+	add_child(number)
+
+	start_y = position.y
+	z_index = 40
+
+
+func _process(delta: float) -> void:
+	age += delta
+	var t: float = age / DURATION
+	if t >= 1.0:
+		queue_free()
+		return
+	# Eases out: quick off the mark, drifting by the end.
+	position.y = start_y - RISE_DISTANCE * (1.0 - pow(1.0 - t, 2.0))
+	modulate.a = 1.0 if t < FADE_START else 1.0 - (t - FADE_START) / (1.0 - FADE_START)
+	queue_redraw()
+
+
+func _draw() -> void:
+	# The plus sign, drawn here rather than as a third child - it is two
+	# strokes and giving it its own node would cost more than it saves.
+	var centre := Vector2(-12.0, 0.0)
+	var arm: float = 5.0
+	NeonDraw.draw_glowing_line(self, centre - Vector2(arm, 0.0), centre + Vector2(arm, 0.0),
+		colour, 1.0, 0.5, colour.darkened(0.8))
+	NeonDraw.draw_glowing_line(self, centre - Vector2(0.0, arm), centre + Vector2(0.0, arm),
+		colour, 1.0, 0.5, colour.darkened(0.8))

Rock.gd

@@ -16,6 +16,13 @@ extends Area2D
 
 signal collected
 
+# By path, not by its `ResourcePickupVFX` global name: a bare class-name
+# reference needs the global class cache already warm, which it is not when
+# this script is reached indirectly - loading Main.tscn from inside a preview
+# scene made it a hard parse error. Same workaround PlanetSetups and
+# PlanetSetupEditor already use.
+const RESOURCE_PICKUP_VFX = preload("res://ResourcePickupVFX.gd")
+
 # Seconds before an uncollected rock disappears. 0 means never, which is what
 # hand-placed surface rocks use - a planet surface is bounded and authored, so
 # nothing accumulates. Ore dropped by a shot asteroid sets a real lifetime,
@@ -98,8 +105,13 @@ func _on_area_entered(area: Area2D) -> void:
 		# spendable once the fleet has flown it back to the mothership.
 		# #56: the hold has a finite total_capacity now - a full fleet must
 		# leave the rock behind rather than despawning it for nothing.
-		if GameState.collect_cargo(1) <= 0:
+		var taken: int = GameState.collect_cargo(1)
+		if taken <= 0:
 			return
+		# #79: say what was picked up, where it was picked up. Parented to the
+		# root rather than to this node, which is about to be freed.
+		RESOURCE_PICKUP_VFX.spawn(get_tree().root, global_position,
+			GameState.RESOURCE_ORE, taken)
 		collected.emit()
 		queue_free()
 

VesselDefinition.gd

@@ -1,6 +1,17 @@
 class_name VesselDefinition
 extends Resource
 
+# The stable internal key: capability strings, unlock ids in vessel_levels,
+# component scene names and every test refer to a vessel by this, NOT by
+# display_name. The two are deliberately allowed to diverge - #77 renamed the
+# "distorder" to the Energy Propulser purely in what the player sees, and
+# nothing underneath had to be migrated for it.
+#
+# Note for editors of the .tres files themselves: Godot's resource format does
+# NOT accept `#` comments inside a [resource] block. One added there parses as
+# part of the preceding value and silently blanks the property after it, which
+# presents as "<blank> did not resolve its definition" a long way from the
+# edit. Comments about the data go here, in the script.
 @export var definition_id: String
 @export var display_name: String
 @export_multiline var description: String

tests/test_distorder_stacking.gd

@@ -2,13 +2,17 @@ extends SceneTree
 
 # Headless gameplay test: run with
 #   godot --headless -s res://tests/test_distorder_stacking.gd
-# Each space-time distorder vessel PAST THE FIRST raises the fleet's speed
+# Energy Propulsers raise the fleet's speed ceiling together, so a second one
-# ceiling by 1.0, so a second one is worth crewing rather than dead weight.
+# is worth crewing rather than dead weight - but with DIMINISHING returns
+# (#77). Each doubling of them adds 1.0, not each vessel: a flat 1.0 apiece
+# meant a fleet that could afford six simply drove at six times cruise and the
+# vessel stopped being a choice.
 #
 # Covers:
 #   A. one vessel gives the original ceiling, so nothing changed for a fleet
-#      that carries a single distorder
+#      that carries a single propulser
-#   B. each additional vessel adds exactly 1.0
+#   B. the ceiling follows log2 of the count - two vessels are worth exactly
+#      what they were worth before the change, and the growth tapers after
 #   C. the fader's full travel reaches the WIDENED ceiling, not the old one
 #   D. losing a vessel mid-boost pulls the fleet back down to the new
 #      ceiling rather than leaving it faster than its crew can sustain
@@ -53,14 +57,33 @@ func _process(delta: float) -> bool:
 					% [game_state.max_fleet_speed_multiplier, GameState.MAX_FLEET_SPEED_MULTIPLIER])
 			print("1 distorder -> ceiling %.1fx" % game_state.max_fleet_speed_multiplier)
 
-			# --- B. each additional vessel adds 1.0 ----------------------
+			# --- B. the ceiling grows with log2 of the count ---------------
+			var previous_gain: float = 1.0
 			for extra in range(1, 4):
 				fleet.add_ship(GameState.VESSEL_DISTORDER)
-				var expected: float = GameState.MAX_FLEET_SPEED_MULTIPLIER + float(extra)
+				var count: int = extra + 1
+				var expected: float = GameState.MAX_FLEET_SPEED_MULTIPLIER \
+					+ log(float(count)) / log(2.0)
 				if not is_equal_approx(game_state.max_fleet_speed_multiplier, expected):
-					return _fail("%d distorders give a ceiling of %.1f, expected %.1f" \
+					return _fail("%d propulsers give a ceiling of %.2f, expected %.2f" \
-						% [extra + 1, game_state.max_fleet_speed_multiplier, expected])
+						% [count, game_state.max_fleet_speed_multiplier, expected])
-				print("%d distorders -> ceiling %.1fx" % [extra + 1, game_state.max_fleet_speed_multiplier])
+				# Each vessel must be worth strictly less than the one before
+				# it. That is the whole point of the change, and asserting the
+				# formula alone would pass just as happily on a linear one.
+				var gain: float = game_state.max_fleet_speed_multiplier \
+					- (GameState.MAX_FLEET_SPEED_MULTIPLIER + log(float(count - 1)) / log(2.0))
+				if count > 2 and gain >= previous_gain:
+					return _fail("propulser %d added %.2f, no less than the %.2f the one before it added - the returns are not diminishing" \
+						% [count, gain, previous_gain])
+				previous_gain = gain
+				print("%d propulsers -> ceiling %.2fx (this one added %.2f)" \
+					% [count, game_state.max_fleet_speed_multiplier, gain])
+
+			# Two propulsers must still be worth exactly what they were before
+			# the change, or an existing fleet was quietly devalued.
+			if not is_equal_approx(GameState.MAX_FLEET_SPEED_MULTIPLIER + log(2.0) / log(2.0),
+					GameState.MAX_FLEET_SPEED_MULTIPLIER + 1.0):
+				return _fail("two propulsers no longer reach the ceiling they used to")
 
 			# --- C. the fader reaches the widened ceiling ----------------
 			# Dragging the track to its top must mean the CURRENT ceiling, or

tests/test_gas_burner_pause.gd

@@ -0,0 +1,159 @@
+extends SceneTree
+
+# Headless gameplay test: run with
+#   godot --headless -s res://tests/test_gas_burner_pause.gd
+# Forgejo #78: a gas burner converts gas the player may want for bombs into
+# energy they may not need yet, and until now it did that relentlessly - the
+# only way to stop it was to demolish it.
+#
+# Covers:
+#   A. the burner offers a "pause" action, and it is its PRIMARY one, so a
+#      single tap on the context button toggles it rather than opening a menu
+#   B. a running burner converts gas into energy
+#   C. a paused one converts nothing, and keeps its gas
+#   D. resuming converts again, and the fraction of a unit already worked
+#      through is not thrown away
+#   E. the button shows what it will DO - pause bars while running, a play
+#      triangle while stopped
+
+var game_state: Node
+var main: Node
+var controller: Node
+var burner_id: int = 0
+var stage: int = 0
+var elapsed: float = 0.0
+var gas_at_pause: int = 0
+var energy_at_pause: int = 0
+
+
+func _initialize() -> void:
+	game_state = root.get_node("GameState")
+	game_state.buildings.clear()
+	game_state.extractors.clear()
+	game_state.transporters.clear()
+	game_state.reset_progression()
+	main = load("res://Main.tscn").instantiate()
+	root.add_child(main)
+	current_scene = main
+	controller = main.get_node("BuildController")
+
+
+func _burner() -> Dictionary:
+	return game_state.find_building(burner_id)
+
+
+func _stock(resource_type: String) -> int:
+	return game_state.building_resource(burner_id, resource_type)
+
+
+func _process(delta: float) -> bool:
+	elapsed += delta
+	match stage:
+		0:
+			if elapsed < 0.3:
+				return false
+			main.get_node("EnemySpawner").set_process(false)
+			main.get_node("AsteroidField").set_process(false)
+
+			# Through the FIELD, not GameState directly: place() both records
+			# the building and spawns its node, and part E needs the node.
+			main.get_node("BuildingField").place(GameState.BUILDING_GAS_BURNER,
+				Vector2(600.0, 0.0))
+			burner_id = int(game_state.buildings[0].id)
+			game_state.building_inventory(burner_id).deposit(GameState.RESOURCE_GAS, 30)
+			if _stock(GameState.RESOURCE_GAS) <= 0:
+				return _fail("could not stock the burner with gas")
+
+			# --- A. it offers pause, as its primary action ----------------
+			var definition: Resource = load("res://BuildingDefinitions.gd") \
+				.get_definition(GameState.BUILDING_GAS_BURNER)
+			var visual: Node = definition.visual_scene.instantiate()
+			var provider: Node = visual.get_node_or_null("ActionProvider")
+			if provider == null:
+				visual.free()
+				return _fail("the gas burner visual has no ActionProvider")
+			var actions: PackedStringArray = provider.actions
+			visual.free()
+			if not Array(actions).has("pause"):
+				return _fail("the gas burner does not offer a pause action: %s" % str(actions))
+			if String(actions[0]) != "pause":
+				return _fail("pause is not the burner's primary action (%s comes first), so it would need a menu rather than one tap" % actions[0])
+			print("gas burner offers pause as its primary action")
+			stage = 1
+			elapsed = 0.0
+			return false
+		1:
+			# --- B. running, it converts ----------------------------------
+			if elapsed < 1.5:
+				return false
+			if _stock(GameState.RESOURCE_ENERGY) <= 0:
+				return _fail("a running burner made no energy in %.1fs" % elapsed)
+			print("running: %d gas left, %d energy made" \
+				% [_stock(GameState.RESOURCE_GAS), _stock(GameState.RESOURCE_ENERGY)])
+
+			if game_state.is_building_paused(burner_id):
+				return _fail("the burner started out paused")
+			if not game_state.toggle_building_paused(burner_id):
+				return _fail("toggling did not pause the burner")
+			gas_at_pause = _stock(GameState.RESOURCE_GAS)
+			energy_at_pause = _stock(GameState.RESOURCE_ENERGY)
+			stage = 2
+			elapsed = 0.0
+			return false
+		2:
+			# --- C. paused, it does nothing -------------------------------
+			if elapsed < 1.5:
+				return false
+			if _stock(GameState.RESOURCE_ENERGY) != energy_at_pause:
+				return _fail("a paused burner made %d more energy" \
+					% (_stock(GameState.RESOURCE_ENERGY) - energy_at_pause))
+			if _stock(GameState.RESOURCE_GAS) != gas_at_pause:
+				return _fail("a paused burner consumed %d gas" \
+					% (gas_at_pause - _stock(GameState.RESOURCE_GAS)))
+			print("paused for %.1fs: no gas burned, no energy made" % elapsed)
+
+			# --- D. resuming works again ----------------------------------
+			if game_state.toggle_building_paused(burner_id):
+				return _fail("toggling a paused burner did not resume it")
+			stage = 3
+			elapsed = 0.0
+			return false
+		3:
+			if elapsed < 1.5:
+				return false
+			if _stock(GameState.RESOURCE_ENERGY) <= energy_at_pause:
+				return _fail("a resumed burner made no further energy")
+			print("resumed: energy %d -> %d" \
+				% [energy_at_pause, _stock(GameState.RESOURCE_ENERGY)])
+
+			# --- E. the icon reports the action, not the state ------------
+			var building: Node = _find_building_node()
+			if building == null:
+				return _fail("no Building node was spawned for the burner")
+			var running_icon: int = controller._building_action_icon(building)
+			game_state.set_building_paused(burner_id, true)
+			var paused_icon: int = controller._building_action_icon(building)
+			game_state.set_building_paused(burner_id, false)
+			if running_icon != IconButton.Icon.PAUSE:
+				return _fail("a running burner's button does not show the pause glyph")
+			if paused_icon != IconButton.Icon.RESUME:
+				return _fail("a paused burner's button does not show the resume glyph")
+			print("button shows pause while running and resume while stopped")
+
+			print("TEST_GAS_BURNER_PAUSE: PASS")
+			quit(0)
+			return true
+	return false
+
+
+func _find_building_node() -> Node:
+	for node in get_nodes_in_group("buildings"):
+		if is_instance_valid(node) and int(node.building_id) == burner_id:
+			return node
+	return null
+
+
+func _fail(message: String) -> bool:
+	print("TEST_GAS_BURNER_PAUSE: FAIL (%s)" % message)
+	quit(1)
+	return true

tests/test_pickup_feedback.gd

@@ -0,0 +1,140 @@
+extends SceneTree
+
+# Headless gameplay test: run with
+#   godot --headless -s res://tests/test_pickup_feedback.gd
+# Forgejo #79: collecting used to be silent - a rock vanished and a number in
+# the corner of the screen changed. Which number, and by how much, was left
+# for the player to notice. A "+N" in the resource's own colour now rises
+# where the pickup happened.
+#
+# Covers:
+#   A. collecting ore raises a marker at the pickup point, carrying the right
+#      resource and amount
+#   B. it is built from the resource catalog's own glyph, so a material added
+#      later cannot end up with one mark in the HUD and another in the world
+#   C. it clears itself up rather than accumulating one node per pickup
+#   D. a pickup that is REFUSED - a full hold - raises nothing, so the marker
+#      never claims something the player did not get
+
+var game_state: Node
+var main: Node
+var fleet: Node
+var stage: int = 0
+var elapsed: float = 0.0
+
+
+func _initialize() -> void:
+	game_state = root.get_node("GameState")
+	game_state.buildings.clear()
+	game_state.extractors.clear()
+	game_state.reset_progression()
+	main = load("res://Main.tscn").instantiate()
+	root.add_child(main)
+	current_scene = main
+	fleet = main.get_node("Fleet")
+
+
+const PICKUP_VFX = preload("res://ResourcePickupVFX.gd")
+
+
+func _markers() -> Array:
+	var found: Array = []
+	for node in root.get_children():
+		if node.get_script() == PICKUP_VFX:
+			found.append(node)
+	return found
+
+
+func _drop_rock_on_fleet() -> Node2D:
+	var rock: Node2D = load("res://Rock.tscn").instantiate()
+	rock.build_shape(7)
+	rock.position = fleet.ships[0].global_position
+	main.add_child(rock)
+	return rock
+
+
+func _process(delta: float) -> bool:
+	elapsed += delta
+	match stage:
+		0:
+			if elapsed < 0.3:
+				return false
+			main.get_node("EnemySpawner").set_process(false)
+			main.get_node("AsteroidField").set_process(false)
+			for hazard in get_nodes_in_group("asteroids") + get_nodes_in_group("rocks"):
+				if is_instance_valid(hazard):
+					hazard.free()
+			fleet.spawn_ships(1, Vector2.ZERO, PackedStringArray([GameState.VESSEL_INTERCEPTOR]))
+			game_state.fleet_inventory.set_amount(GameState.RESOURCE_ORE, 0)
+			if not _markers().is_empty():
+				return _fail("a pickup marker existed before anything was collected")
+			_drop_rock_on_fleet()
+			stage = 1
+			elapsed = 0.0
+			return false
+		1:
+			if elapsed < 0.4:
+				return false
+			# --- A. one marker, right resource, right amount --------------
+			var markers: Array = _markers()
+			if markers.size() != 1:
+				return _fail("collecting one rock raised %d markers" % markers.size())
+			var marker: Node2D = markers[0]
+			if game_state.fleet_resource(GameState.RESOURCE_ORE) <= 0:
+				return _fail("the rock was not actually collected, so the marker is reporting a pickup that did not happen")
+			if marker.global_position.distance_to(fleet.ships[0].global_position) > 120.0:
+				return _fail("the marker appeared %.0f away from where the pickup happened" \
+					% marker.global_position.distance_to(fleet.ships[0].global_position))
+
+			# --- B. built from the catalog's own glyph --------------------
+			var definitions: Script = load("res://ResourceDefinitions.gd")
+			var ore: Resource = definitions.get_definition(GameState.RESOURCE_ORE)
+			if not marker.colour.is_equal_approx(ore.color):
+				return _fail("the marker is %s, but ore is %s" % [marker.colour, ore.color])
+			var glyph_scripts: Array = []
+			for child in marker.get_children():
+				glyph_scripts.append(child.get_script())
+			var probe: Node = ore.glyph_scene.instantiate()
+			var expected: Script = probe.get_script()
+			probe.free()
+			if expected not in glyph_scripts:
+				return _fail("the marker does not use the ore glyph the resource catalog defines")
+			print("collecting ore raised one marker at the pickup point, in ore's own colour and glyph")
+			stage = 2
+			elapsed = 0.0
+			return false
+		2:
+			# --- C. it cleans itself up -----------------------------------
+			if elapsed < 1.5:
+				return false
+			if not _markers().is_empty():
+				return _fail("%d marker(s) still on screen 1.5s later - they accumulate" % _markers().size())
+			print("marker cleared itself up")
+
+			# --- D. a refused pickup says nothing -------------------------
+			# Hold filled to capacity, so collect_cargo takes nothing.
+			var capacity: int = game_state.fleet_inventory.total_capacity
+			if capacity < 0:
+				return _fail("the fleet hold has no capacity limit, so a refused pickup cannot be staged")
+			game_state.fleet_inventory.set_amount(GameState.RESOURCE_ORE, capacity)
+			_drop_rock_on_fleet()
+			stage = 3
+			elapsed = 0.0
+			return false
+		3:
+			if elapsed < 0.4:
+				return false
+			if not _markers().is_empty():
+				return _fail("a full hold refused the rock but a marker claimed it was collected")
+			print("a pickup refused by a full hold raises no marker")
+
+			print("TEST_PICKUP_FEEDBACK: PASS")
+			quit(0)
+			return true
+	return false
+
+
+func _fail(message: String) -> bool:
+	print("TEST_PICKUP_FEEDBACK: FAIL (%s)" % message)
+	quit(1)
+	return true