Add gas giant resource system

BuildController.gd

@@ -643,7 +643,7 @@ func _show_building_info(type: String) -> void:
 			lines.append("%s already has an extractor." % planet.planet_name)
 			can_build = false
 		else:
-			lines.append("Will mine %s." % planet.planet_name)
+			lines.append("Will mine %s from %s." % ["gas" if planet.resource_type == "gas" else "ore", planet.planet_name])
 	elif can_build and type == GameState.BUILDING_MOTHERSHIP and GameState.has_mothership():
 		lines.append("WARNING: only one may exist - this destroys your current one.")
 
@@ -685,7 +685,7 @@ func _confirm_build() -> void:
 		if not GameState.spend(GameState.EXTRACTOR_COST):
 			build_status.text = "Not enough rocks (need %d, have %d)" % [GameState.EXTRACTOR_COST, GameState.rocks]
 			return
-		GameState.add_extractor(planet.planet_name, planet.position)
+		GameState.add_extractor(planet.planet_name, planet.position, planet.resource_type)
 		build_menu.visible = false
 		return
 

GameState.gd

@@ -28,6 +28,11 @@ var explored_chunks: Dictionary = {}
 # first - drop this back to 0 for a real playthrough.
 var rocks: int = 500
 
+# Gas is a second, banked resource. It is deliberately separate from ore:
+# construction still spends ore, while future gas technologies can consume
+# gas without making the two materials silently interchangeable.
+var gas: int = 0
+
 # Ore the fleet is physically carrying and has not delivered yet (#14). Mining
 # fills this, not `rocks`: ore is cargo until the fleet brings it home, so a
 # long mining run is a real trip with something to lose rather than instant
@@ -772,7 +777,7 @@ func rotate_formation(radians: float) -> void:
 # Extractors mine into their OWN local stock. They do not own a magical
 # hauler: ore becomes spendable only when a hub-stationed transporter picks
 # up a full load and physically delivers it to the mothership. Entries are
-# {"position", "planet_name", "stock", "mining_progress"}.
+# {"position", "planet_name", "resource_type", "stock", "mining_progress"}.
 const EXTRACTOR_RATE: float = 2.0  # ore per second
 
 var extractors: Array = []
@@ -788,10 +793,11 @@ func has_extractor_at(planet_name: String) -> bool:
 signal extractor_added(planet_name: String)
 
 
-func add_extractor(planet_name: String, at_position: Vector2) -> void:
+func add_extractor(planet_name: String, at_position: Vector2, resource_type: String = "ore") -> void:
 	extractors.append({
 		"position": at_position,
 		"planet_name": planet_name,
+		"resource_type": resource_type,
 		"stock": 0,
 		"mining_progress": 0.0,
 	})
@@ -917,7 +923,7 @@ func _station_transporter(built_at: Vector2) -> void:
 		return
 	transporters.append({
 		"hub_id": int(hub.id), "state": TRANSPORTER_RETURNING, "target_id": 0,
-		"carrying": 0, "progress": 0.0, "from": built_at, "to": hub.position,
+		"carrying": 0, "resource_type": "ore", "progress": 0.0, "from": built_at, "to": hub.position,
 	})
 
 
@@ -977,6 +983,7 @@ func _dispatch_transporters() -> void:
 		if chosen_extractor.is_empty():
 			return
 		chosen_extractor.extractor_index = i
+		chosen_extractor.resource_type = String(extractor.get("resource_type", "ore"))
 		chosen_extractor.target_id = 0
 		_begin_leg(chosen_extractor, transporter_position(chosen_extractor), extractor.position,
 			TRANSPORTER_TO_EXTRACTOR)
@@ -1058,9 +1065,13 @@ func _arrive(t: Dictionary) -> void:
 				return
 			extractor.stock = int(extractor.stock) - load
 			t.carrying = load
+			t.resource_type = String(extractor.get("resource_type", "ore"))
 			_begin_leg(t, here, get_mothership_position(), TRANSPORTER_TO_MOTHERSHIP_FROM_EXTRACTOR)
 		TRANSPORTER_TO_MOTHERSHIP_FROM_EXTRACTOR:
-			# Bank only on arrival; while in flight the ore remains in carrying.
+			# Bank only on arrival; cargo retains the extractor's resource type.
+			if String(t.get("resource_type", "ore")) == "gas":
+				gas += int(t.carrying)
+			else:
 				rocks += int(t.carrying)
 			t.carrying = 0
 			t.extractor_index = -1

GasCounter.gd

@@ -0,0 +1,16 @@
+extends NeonNumber
+
+# Banked gas companion to the ore counter. Keeping it as the same neon
+# numeral language makes both resources equally legible without implying gas
+# can pay for ore-only construction.
+const GAS_GLOW: Color = Color(0.85, 0.52, 1.0)
+const GAS_CORE: Color = Color(0.2, 0.04, 0.28)
+
+
+func _ready() -> void:
+	glow_color = GAS_GLOW
+	core_color = GAS_CORE
+
+
+func _process(_delta: float) -> void:
+	set_amount(GameState.gas)

Main.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=21 format=3]
+[gd_scene load_steps=22 format=3]
 
 [ext_resource type="Script" path="res://Starfield.gd" id="1"]
 [ext_resource type="Script" path="res://Fleet.gd" id="2"]
@@ -23,6 +23,7 @@
 [ext_resource type="Script" path="res://CargoCounter.gd" id="22"]
 [ext_resource type="Script" path="res://TransporterField.gd" id="23"]
 [ext_resource type="Script" path="res://ResourceBar.gd" id="24"]
+[ext_resource type="Script" path="res://GasCounter.gd" id="25"]
 
 [sub_resource type="ShaderMaterial" id="1"]
 shader = ExtResource("5")
@@ -91,6 +92,34 @@ offset_bottom = 92
 script = ExtResource("16")
 digit_height = 60.0
 
+[node name="OreCaption" type="Label" parent="UI"]
+mouse_filter = 2
+offset_left = 28
+offset_top = 22
+offset_right = 120
+offset_bottom = 48
+theme_override_font_sizes/font_size = 18
+text = "ORE"
+
+[node name="GasCounter" type="Control" parent="UI"]
+mouse_filter = 2
+offset_left = 336
+offset_top = 24
+offset_right = 628
+offset_bottom = 92
+script = ExtResource("25")
+digit_height = 60.0
+
+[node name="GasCaption" type="Label" parent="UI"]
+mouse_filter = 2
+offset_left = 336
+offset_top = 22
+offset_right = 428
+offset_bottom = 48
+theme_override_font_sizes/font_size = 18
+theme_override_colors/font_color = Color(0.85, 0.52, 1, 1)
+text = "GAS"
+
 [node name="CargoCounter" type="Control" parent="UI"]
 mouse_filter = 2
 offset_left = 28

Planet.gd

@@ -11,7 +11,8 @@ extends Node2D
 # while the fleet as a whole was clearly sitting on the planet.
 
 @export var planet_name: String = ""
-@export var planet_type: String = "big_stable_asteroid"
+@export var planet_type: String = "rocky"
+@export var resource_type: String = "ore"
 @export var landing_radius: float = 140.0
 # Set by whoever spawns this planet (PlanetField, seeded from the chunk's
 # own coordinates) so the outline shape is stable across respawns of the
@@ -36,6 +37,7 @@ const DERRICK_HALF_WIDTH: float = 16.0
 # only at _ready() left the planet looking untouched until it happened to
 # despawn and respawn.
 var shows_extractor: bool = false
+var gas_phase: float = 0.0
 
 
 func _ready() -> void:
@@ -54,6 +56,12 @@ func _ready() -> void:
 	queue_redraw()
 
 
+func _process(delta: float) -> void:
+	if planet_type == "gas_giant":
+		gas_phase += delta
+		queue_redraw()
+
+
 func _on_extractor_added(built_on: String) -> void:
 	# Only the planet it was actually built on, and only a redraw when the
 	# answer really changed - every other planet in range gets this too.
@@ -103,6 +111,28 @@ func extractor_derrick_points() -> PackedVector2Array:
 
 
 func _draw() -> void:
+	if planet_type == "gas_giant":
+		_draw_gas_giant()
+		if shows_extractor:
+			NeonDraw.draw_glowing_polygon(self, extractor_derrick_points(), EXTRACTOR_MARKER_COLOR, 1.0)
+		return
 	NeonDraw.draw_glowing_polygon(self, shape_points, Color(0.6, 0.55, 0.5), 1.0)
 	if shows_extractor:
 		NeonDraw.draw_glowing_polygon(self, extractor_derrick_points(), EXTRACTOR_MARKER_COLOR, 1.0)
+
+
+func _draw_gas_giant() -> void:
+	# A round, animated giant with drifting latitudinal bands. It is visibly
+	# unlike the rocky outline and keeps moving even while the fleet is idle.
+	var rim := PackedVector2Array()
+	for i in range(32):
+		var a := TAU * float(i) / 32.0
+		rim.append(Vector2(cos(a) * 118.0, sin(a) * 118.0))
+	NeonDraw.draw_glowing_polygon(self, rim, Color(0.4, 0.78, 1.0), 0.9)
+	for row in [-62.0, -28.0, 8.0, 43.0, 73.0]:
+		var band := PackedVector2Array()
+		var half_width: float = sqrt(maxf(0.0, 118.0 * 118.0 - row * row))
+		for i in range(15):
+			var x := lerpf(-half_width, half_width, float(i) / 14.0)
+			band.append(Vector2(x, row + sin(x * 0.045 + gas_phase * 1.6 + row) * 7.0))
+		NeonDraw.draw_glowing_path(self, band, Color(0.85, 0.52, 1.0), 0.75, 0.65)

PlanetField.gd

@@ -83,6 +83,8 @@ func _spawn_chunk_planet(chunk: Vector2i) -> void:
 	planet.position = origin + data.local_pos
 	planet.planet_name = data.name
 	planet.shape_seed = data.shape_seed
+	planet.planet_type = String(data.get("planet_type", "rocky"))
+	planet.resource_type = String(data.get("resource_type", "ore"))
 	# Deferred: update_chunks() can run synchronously from inside a
 	# parent's own _ready() chain (forced once right after the fleet is
 	# positioned, to avoid a pop-in on scene load) - Godot refuses a

ResourceBar.gd

@@ -41,6 +41,7 @@ const RULE_COLOR: Color = Color(0.25, 0.55, 0.7)
 
 var _numbers: Array[NeonNumber] = []
 var _captions: Array[Label] = []
+var _gas_caption: Label
 
 
 func _ready() -> void:
@@ -69,6 +70,11 @@ func _ready() -> void:
 
 	_layout()
 	resized.connect(_layout)
+	_gas_caption = Label.new()
+	_gas_caption.mouse_filter = Control.MOUSE_FILTER_IGNORE
+	_gas_caption.add_theme_font_size_override("font_size", 20)
+	_gas_caption.add_theme_color_override("font_color", Color(0.85, 0.52, 1.0))
+	add_child(_gas_caption)
 
 
 func _layout() -> void:
@@ -80,9 +86,14 @@ func _layout() -> void:
 		# The hexagon and digits are drawn from the node's own origin, so the
 		# number is positioned rather than sized.
 		_numbers[i].position = Vector2(x, CAPTION_HEIGHT + CAPTION_GAP)
+	if _gas_caption != null:
+		_gas_caption.position = Vector2(size.x - 110.0, 2.0)
+		_gas_caption.size = Vector2(106.0, CAPTION_HEIGHT)
+		_gas_caption.horizontal_alignment = HORIZONTAL_ALIGNMENT_RIGHT
 
 
 func _process(_delta: float) -> void:
+	_gas_caption.text = "GAS %d" % GameState.gas
 	_numbers[0].set_amount(GameState.rocks)
 	_numbers[1].set_amount(GameState.fleet_cargo)
 

WorldGen.gd

@@ -19,6 +19,7 @@ const PLANET_NAMES: Array = [
 	"Drift Anchor", "Stonefall", "Grey Watch", "Silent Quarry",
 	"Baros Rock", "Umbra Point",
 ]
+const GAS_GIANT_NAMES: Array = ["Aurelia", "Boreas", "Cerulean Deep", "Helios Major", "Vesper"]
 
 static var _noise: FastNoiseLite
 static var _planet_noise: FastNoiseLite
@@ -79,7 +80,13 @@ static func planet_data_at_chunk(chunk: Vector2i) -> Dictionary:
 	var local_pos: Vector2 = Vector2(rng.randf() * CHUNK_SIZE, rng.randf() * CHUNK_SIZE)
 	var planet_name: String = PLANET_NAMES[rng.randi() % PLANET_NAMES.size()]
 	var shape_seed: int = rng.randi()
-	return {"local_pos": local_pos, "name": planet_name, "shape_seed": shape_seed}
+	# A stable per-chunk roll makes gas giants persistent landmarks rather
+	# than a different resource whenever the scene reloads.
+	var gas_giant: bool = rng.randf() < 0.28
+	if gas_giant:
+		planet_name = GAS_GIANT_NAMES[rng.randi() % GAS_GIANT_NAMES.size()]
+	return {"local_pos": local_pos, "name": planet_name, "shape_seed": shape_seed,
+		"planet_type": "gas_giant" if gas_giant else "rocky", "resource_type": "gas" if gas_giant else "ore"}
 
 
 static func biome_color(biome: int) -> Color:

tests/test_gas_system.gd

@@ -0,0 +1,64 @@
+extends SceneTree
+
+# Forgejo #27: gas giants are deterministic animated gas sources, and the
+# existing transporter route carries their gas without converting it to ore.
+
+var game_state: 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.transporters.clear()
+	game_state.gas = 0
+	game_state.rocks = 0
+
+
+func _process(delta: float) -> bool:
+	elapsed += delta
+	if stage == 0:
+		var found_giant: bool = false
+		for x in range(-12, 13):
+			for y in range(-12, 13):
+				var data: Dictionary = WorldGen.planet_data_at_chunk(Vector2i(x, y))
+				if String(data.get("planet_type", "")) == "gas_giant":
+					found_giant = String(data.get("resource_type", "")) == "gas"
+					break
+			if found_giant:
+				break
+		if not found_giant:
+			return _fail("world generation produced no deterministic gas giant")
+		var giant: Node2D = load("res://Planet.tscn").instantiate()
+		giant.planet_type = "gas_giant"
+		giant._process(0.5)
+		if giant.gas_phase <= 0.0:
+			return _fail("gas giant animation did not advance")
+		giant.free()
+
+		game_state.add_building(GameState.BUILDING_MOTHERSHIP, Vector2.ZERO)
+		game_state.add_building(GameState.BUILDING_TRANSPORT_HUB, Vector2(100, 0))
+		game_state.add_extractor("Aurelia", Vector2(400, 0), "gas")
+		game_state.extractors[0].stock = game_state.transporter_load_limit()
+		game_state.transporters.append({"hub_id": 2, "state": GameState.TRANSPORTER_TO_EXTRACTOR,
+			"target_id": 0, "extractor_index": 0, "carrying": 0, "resource_type": "gas",
+			"progress": 1.0, "from": Vector2(100, 0), "to": Vector2(400, 0)})
+		game_state._arrive(game_state.transporters[0])
+		if game_state.transporters[0].state != GameState.TRANSPORTER_TO_MOTHERSHIP_FROM_EXTRACTOR:
+			return _fail("transporter did not collect gas from the extractor")
+		game_state._arrive(game_state.transporters[0])
+		if game_state.gas != game_state.transporter_load_limit() or game_state.rocks != 0:
+			return _fail("gas delivery banked gas=%d ore=%d" % [game_state.gas, game_state.rocks])
+		print("gas giant animated; transporter banked %d gas without creating ore" % game_state.gas)
+		print("TEST_GAS_SYSTEM: PASS")
+		quit(0)
+		return true
+	return false
+
+
+func _fail(message: String) -> bool:
+	print("TEST_GAS_SYSTEM: FAIL (%s)" % message)
+	quit(1)
+	return true