Initial commit. Implement music sync features.

rhythm_game/note_layout.gd

@@ -0,0 +1,84 @@
+#TODO Split class into two.
+# One should be responsible for storing arrays of data, like a NoteData class?
+# Another represents a slice of the data, NoteView.
+# Before that, figure out how the part of a hold note between the hold start
+# and hold end will be implemented.
+class_name NoteLayout extends Node
+
+## Controls at what beat notes are visible.
+@export_group("Note View Offset")
+## At what beat offset from the current beat will notes will be visible.
+## Example, spawn = 4.0 means notes are spawned 4 beats before
+## they are meant to be hit.
+@export var spawn: float = 4.0
+
+## At what beat offset from the current beat will notes be invisible.
+## Example, despawn = 4.0 means notes are despawned 4 beats after
+## they are meant to be hit.
+@export var despawn: float = 4.0
+
+
+## The index in notes of the first active note.
+func start() -> int:
+	return _start
+
+
+## The index in notes after the last active note.
+func end() -> int:
+	return _end
+
+
+func size() -> int:
+	return _beat.size()
+
+
+func beat(index: int) -> float:
+	return _beat[index]
+
+
+func lane(index: int) -> int:
+	return _lane[index]
+
+
+func type(index: int) -> Note.TYPE:
+	return _type[index]
+
+
+# ======= IMPLEMENTATION ======== #
+
+# All notes in the chart, arranged by ascending beat.
+var _beat: Array[float] = []
+var _lane: Array[int] = []
+var _type: Array[Note.TYPE] = []
+
+var _start: int = 0
+var _end: int = 0
+
+
+func _push_note(_note: Note) -> void:
+	pass
+
+
+# TODO FIX THESE
+func _update_forward(new_beat: float) -> void:
+	var spawn_beat = new_beat + spawn
+	
+	while _end < size() and _beat[_end] <= spawn_beat:
+		_end += 1
+	
+	var despawn_beat = new_beat - despawn
+	
+	while _start < size() and _beat[_start] < despawn_beat:
+		_start += 1
+
+# TODO FIX THESE
+#func _update_backward(new_beat: float) -> void:
+	#var spawn_beat = new_beat + note_spawn_offset
+	#
+	#while _end >= 0 and _beat[_end] > spawn_beat:
+		#_end -= 1
+	#
+	#var despawn_beat = new_beat - note_despawn_offset
+	#
+	#while _start >= 0 and _beat[_start] < despawn_beat:
+		#_start -= 1