Initial work on audio layers

project.godot

@@ -27,10 +27,6 @@ config/windows_native_icon="res://assets/graphics/icons/icon.ico"
 config/ExtensionsAPI_Version=5
 config/Pxo_Version=4
 
-[audio]
-
-driver/driver="Dummy"
-
 [autoload]
 
 Global="*res://src/Autoload/Global.gd"

src/Autoload/ExtensionsApi.gd

@@ -631,7 +631,7 @@ class ProjectAPI:
 
 	## Returns the current cel.
 	## Cel type can be checked using function [method get_class_name] inside the cel
-	## type can be GroupCel, PixelCel, Cel3D, or BaseCel.
+	## type can be GroupCel, PixelCel, Cel3D, CelTileMap, AudioCel or BaseCel.
 	func get_current_cel() -> BaseCel:
 		return current_project.get_current_cel()
 

src/Autoload/Global.gd

@@ -14,7 +14,7 @@ signal cel_switched  ## Emitted whenever you select a different cel.
 signal project_data_changed(project: Project)  ## Emitted when project data is modified.
 signal font_loaded  ## Emitted when a new font has been loaded, or an old one gets unloaded.
 
-enum LayerTypes { PIXEL, GROUP, THREE_D, TILEMAP }
+enum LayerTypes { PIXEL, GROUP, THREE_D, TILEMAP, AUDIO }
 enum GridTypes { CARTESIAN, ISOMETRIC, ALL }
 ## ## Used to tell whether a color is being taken from the current theme,
 ## or if it is a custom color.

src/Autoload/Tools.gd

@@ -800,7 +800,10 @@ func _cel_switched() -> void:
 	var layer: BaseLayer = Global.current_project.layers[Global.current_project.current_layer]
 	var layer_type := layer.get_layer_type()
 	# Do not make any changes when its the same type of layer, or a group layer
-	if layer_type == _curr_layer_type or layer_type == Global.LayerTypes.GROUP:
+	if (
+		layer_type == _curr_layer_type
+		or layer_type in [Global.LayerTypes.GROUP, Global.LayerTypes.AUDIO]
+	):
 		return
 	_show_relevant_tools(layer_type)
 

src/Classes/Cels/AudioCel.gd

@@ -0,0 +1,18 @@
+class_name AudioCel
+extends BaseCel
+## A class for the properties of cels in AudioLayers.
+## The term "cel" comes from "celluloid" (https://en.wikipedia.org/wiki/Cel).
+
+
+func _init(_opacity := 1.0) -> void:
+	opacity = _opacity
+	image_texture = ImageTexture.new()
+
+
+func get_image() -> Image:
+	var image := Global.current_project.new_empty_image()
+	return image
+
+
+func get_class_name() -> String:
+	return "AudioCel"

src/Classes/Layers/AudioLayer.gd

@@ -0,0 +1,36 @@
+class_name AudioLayer
+extends BaseLayer
+
+signal audio_changed
+
+var audio: AudioStream:
+	set(value):
+		audio = value
+		audio_changed.emit()
+
+
+func _init(_project: Project, _name := "") -> void:
+	project = _project
+	name = _name
+
+
+# Overridden Methods:
+func serialize() -> Dictionary:
+	var data := {"name": name, "type": get_layer_type()}
+	return data
+
+
+func deserialize(dict: Dictionary) -> void:
+	super.deserialize(dict)
+
+
+func get_layer_type() -> int:
+	return Global.LayerTypes.AUDIO
+
+
+func new_empty_cel() -> AudioCel:
+	return AudioCel.new()
+
+
+func set_name_to_default(number: int) -> void:
+	name = tr("Audio track") + " %s" % number

src/Classes/Project.gd

@@ -640,10 +640,10 @@ func find_first_drawable_cel(frame := frames[current_frame]) -> BaseCel:
 	var result: BaseCel
 	var cel := frame.cels[0]
 	var i := 0
-	while cel is GroupCel and i < layers.size():
+	while (cel is GroupCel or cel is AudioCel) and i < layers.size():
 		cel = frame.cels[i]
 		i += 1
-	if not cel is GroupCel:
+	if cel is not GroupCel and cel is not AudioCel:
 		result = cel
 	return result
 

src/UI/Timeline/AnimationTimeline.gd

@@ -855,6 +855,8 @@ func _on_add_layer_list_id_pressed(id: int) -> void:
 			Global.LayerTypes.THREE_D:
 				layer = Layer3D.new(project)
 				SteamManager.set_achievement("ACH_3D_LAYER")
+			Global.LayerTypes.AUDIO:
+				layer = AudioLayer.new(project)
 		add_layer(layer, project)
 
 

src/UI/Timeline/AnimationTimeline.tscn

@@ -240,7 +240,7 @@ offset_left = -22.0
 offset_top = -10.0
 offset_bottom = 10.0
 mouse_default_cursor_shape = 2
-item_count = 4
+item_count = 5
 popup/item_0/text = "Add Pixel Layer"
 popup/item_1/text = "Add Group Layer"
 popup/item_1/id = 1
@@ -248,6 +248,8 @@ popup/item_2/text = "Add 3D Layer"
 popup/item_2/id = 2
 popup/item_3/text = "Add Tilemap Layer"
 popup/item_3/id = 3
+popup/item_4/text = "Add Audio Layer"
+popup/item_4/id = 4
 
 [node name="TextureRect" type="TextureRect" parent="TimelineContainer/TimelineButtons/LayerTools/MarginContainer/LayerSettingsContainer/LayerButtons/AddLayer/AddLayerList"]
 layout_mode = 0

src/UI/Timeline/LayerButton.gd

@@ -15,6 +15,7 @@ var button_pressed := false:
 	get:
 		return main_button.button_pressed
 
+var audio_player: AudioStreamPlayer
 @onready var properties: AcceptDialog = Global.control.find_child("LayerProperties")
 @onready var main_button := %LayerMainButton as Button
 @onready var expand_button := %ExpandButton as BaseButton
@@ -31,7 +32,7 @@ var button_pressed := false:
 func _ready() -> void:
 	main_button.layer_index = layer_index
 	main_button.hierarchy_depth_pixel_shift = HIERARCHY_DEPTH_PIXEL_SHIFT
-	Global.cel_switched.connect(func(): z_index = 1 if button_pressed else 0)
+	Global.cel_switched.connect(_on_cel_switched)
 	var layer := Global.current_project.layers[layer_index]
 	layer.name_changed.connect(func(): label.text = layer.name)
 	layer.visibility_changed.connect(update_buttons)
@@ -39,6 +40,10 @@ func _ready() -> void:
 		linked_button.visible = true
 	elif layer is GroupLayer:
 		expand_button.visible = true
+	elif layer is AudioLayer:
+		audio_player = AudioStreamPlayer.new()
+		audio_player.stream = layer.audio
+		add_child(audio_player)
 	custom_minimum_size.y = Global.animation_timeline.cel_size
 	label.text = layer.name
 	line_edit.text = layer.name
@@ -56,6 +61,12 @@ func _ready() -> void:
 	update_buttons()
 
 
+func _on_cel_switched() -> void:
+	z_index = 1 if button_pressed else 0
+	if is_instance_valid(audio_player):
+		audio_player.play(Global.current_project.current_frame / Global.current_project.fps)
+
+
 func update_buttons() -> void:
 	var layer := Global.current_project.layers[layer_index]
 	if layer is GroupLayer:

src/UI/Timeline/LayerButton.tscn

@@ -169,7 +169,6 @@ caret_blink_interval = 0.5
 disable_3d = true
 item_count = 2
 item_0/text = "Properties"
-item_0/id = 0
 item_1/text = "Clipping mask"
 item_1/checkable = 1
 item_1/id = 1