Refactor rhythm action architecture

autoload/rhythm_manager.gd

@@ -0,0 +1,167 @@
+extends AudioStreamPlayer
+
+signal beat_ticked(beat_index: int)
+signal judgement_made(quality: StringName, offset_ms: float)
+signal action_judged(action_name: StringName, rating: Dictionary)
+
+@export var bpm: float = 120.0:
+	set(value):
+		bpm = maxf(1.0, value)
+		beat_time = 60.0 / bpm
+@export var measures := 4
+@export var beat_offset := 0.0
+@export var perfect_window := 0.060
+@export var good_window := 0.120
+@export var bad_window := 0.200
+@export var judgement_scale := 1.0
+@export var starts_on_ready := true
+
+const DEFAULT_STREAM_PATH := "res://assets/audio/song.ogg"
+
+var beat_time := 0.5
+var beat_index := 0
+var running := false
+
+var _start_time_usec := 0
+var _last_reported_beat := -1
+
+
+func _ready() -> void:
+	if stream == null and DisplayServer.get_name() != "headless":
+		stream = load(DEFAULT_STREAM_PATH)
+	volume_db = -10.0
+	beat_time = 60.0 / maxf(1.0, bpm)
+	var bus := _event_bus_or_null()
+	if bus != null and not bus.is_connected("rhythm_action_requested", _on_rhythm_action_requested):
+		bus.connect("rhythm_action_requested", _on_rhythm_action_requested)
+	if starts_on_ready:
+		start()
+
+
+func _physics_process(_delta: float) -> void:
+	if not running:
+		return
+	var adjusted_position := _apply_beat_offset(song_position())
+	beat_index = int(floor(adjusted_position / beat_time))
+	if _last_reported_beat < beat_index:
+		_last_reported_beat = beat_index
+		beat_ticked.emit(beat_index)
+		var bus := _event_bus_or_null()
+		if bus != null:
+			bus.emit_signal("beat_ticked", beat_index)
+
+
+func configure(next_bpm: float, next_measures: int, next_beat_offset: float, next_windows := Vector3(0.060, 0.120, 0.200)) -> void:
+	bpm = next_bpm
+	measures = next_measures
+	beat_offset = next_beat_offset
+	perfect_window = next_windows.x
+	good_window = next_windows.y
+	bad_window = next_windows.z
+
+
+func start() -> void:
+	running = true
+	_start_time_usec = Time.get_ticks_usec()
+	beat_index = 0
+	_last_reported_beat = -1
+	if stream != null and not playing:
+		play()
+
+
+func stop_manager() -> void:
+	if playing:
+		stop()
+	running = false
+
+
+func _exit_tree() -> void:
+	if playing:
+		stop()
+	stream = null
+
+
+func song_position() -> float:
+	if running and playing:
+		var current_position := get_playback_position() + AudioServer.get_time_since_last_mix()
+		current_position -= AudioServer.get_output_latency()
+		return maxf(0.0, current_position)
+	if running:
+		return float(Time.get_ticks_usec() - _start_time_usec) / 1000000.0
+	return 0.0
+
+
+func judge(input_timestamp_ms: float) -> Dictionary:
+	return get_rating_for_time(input_timestamp_ms / 1000.0)
+
+
+func judge_action(action_name: StringName) -> Dictionary:
+	var rating := get_current_rating()
+	rating["action"] = action_name
+	action_judged.emit(action_name, rating)
+	judgement_made.emit(StringName(str(rating.get("label", "miss"))), float(rating.get("diff", INF)) * 1000.0)
+	var bus := _event_bus_or_null()
+	if bus != null:
+		bus.emit_signal("judgement_made", StringName(str(rating.get("label", "miss"))), float(rating.get("diff", INF)) * 1000.0)
+		bus.emit_signal("action_judged", action_name, rating)
+	return rating
+
+
+func get_current_rating() -> Dictionary:
+	return get_rating_for_time(song_position())
+
+
+func get_rating_for_time(time_seconds: float) -> Dictionary:
+	var adjusted_time := _apply_beat_offset(time_seconds)
+	if adjusted_time < 0.0:
+		return _rating_result(&"miss", Color("ff0055"), 0, 0.0, INF, INF)
+
+	var nearest_beat := int(round(adjusted_time / beat_time))
+	var nearest_beat_time := nearest_beat * beat_time
+	var diff := adjusted_time - nearest_beat_time
+	var abs_diff := absf(diff)
+	var scale := maxf(0.01, judgement_scale)
+
+	if abs_diff <= perfect_window * scale:
+		return _rating_result(&"perfect", Color("00f2ff"), nearest_beat, nearest_beat_time, diff, abs_diff)
+	if abs_diff <= good_window * scale:
+		return _rating_result(&"good", Color("ffffff"), nearest_beat, nearest_beat_time, diff, abs_diff)
+	if abs_diff <= bad_window * scale:
+		return _rating_result(&"bad", Color("ffaa00"), nearest_beat, nearest_beat_time, diff, abs_diff)
+	return _rating_result(&"miss", Color("ff0055"), nearest_beat, nearest_beat_time, diff, abs_diff)
+
+
+func get_current_beat_progress() -> float:
+	return get_beat_progress_for_time(song_position())
+
+
+func get_beat_progress_for_time(time_seconds: float) -> float:
+	var adjusted_time := _apply_beat_offset(time_seconds)
+	if adjusted_time < 0.0:
+		return 0.0
+	return fposmod(adjusted_time, beat_time) / beat_time
+
+
+func _on_rhythm_action_requested(action_name: StringName) -> void:
+	judge_action(action_name)
+
+
+func _apply_beat_offset(time_seconds: float) -> float:
+	return time_seconds + beat_offset
+
+
+func _rating_result(label: StringName, color: Color, nearest_beat: int, nearest_beat_time: float, diff: float, abs_diff: float) -> Dictionary:
+	return {
+		"label": str(label),
+		"color": color,
+		"nearest_beat": nearest_beat,
+		"nearest_beat_time": nearest_beat_time,
+		"diff": diff,
+		"abs_diff": abs_diff,
+	}
+
+
+func _event_bus_or_null() -> Node:
+	if not is_inside_tree():
+		return null
+	return get_tree().root.get_node_or_null("EventBus")