############################################################
# SCENE LOADER
# Loads scenes and does all the nitty gritty work
# Dispatches 3 signals:
# "START" when a scene begins loading, with the scene
# path as an argument
# "DONE" when a scene has loaded, with the scene resource
# as an argument
# "PROGRESS" as the scene loads, with the percentage
# as an argument (as a value between 0 and 1)
# "ERROR" when an error has occured, with the error as
# an argument
#
# Useful methods:
# - load_scene(string path): begins loading a scene
# - free_current_scene(): removes the scene from the tree
# - set_initial_scene(node scene): if you already have
# a scene set through the editor, this will set it
# as the current scene so it can be removed when
# loading a new one
############################################################
static func instance(node):
var loader = Loader.new()
node.add_child(loader)
return loader
class Loader extends Node:
var current_scene
var loader
var wait_frames
var time_max = 100
var progress = 0
var artificial_slow_down = false
var artificial_slow_down_frames = 60
var artificial_slow_down_current = 60
var done = false
signal DONE(scene_resource)
signal ERROR
signal PROGRESS(percent)
signal START(scene_path)
func slow_down(frames=60):
artificial_slow_down = true
artificial_slow_down_current = frames
artificial_slow_down_frames = frames
func free_current_scene():
if current_scene && current_scene.get_ref():
current_scene.get_ref().queue_free()
func load_scene(path):
emit_signal("START",path)
progress = 0
done = false
loader = ResourceLoader.load_interactive(path)
if loader == null:
show_error("scene at "+path+" could not be loaded")
return
free_current_scene()
wait_frames = 1
set_process(true)
func update_progress():
if !done:
progress = float(loader.get_stage()) / loader.get_stage_count()
else:
progress = 1
emit_signal("PROGRESS",progress)
func get_progress():
return progress
func get_stage():
return loader.get_stage()
func get_stage_count():
return loader.get_stage_count()
func set_new_scene(scene_resource):
var scene_instance = scene_resource.instance()
current_scene = weakref(scene_instance)
done = true
update_progress()
emit_signal("DONE",scene_instance)
func set_initial_scene(node):
if node:
current_scene = weakref(node)
func get_scene():
if current_scene && current_scene.get_ref():
return current_scene.get_ref()
func _process(time):
if loader == null:
set_process(false)
return
if wait_frames > 0:
wait_frames -= 1
return
if artificial_slow_down:
if artificial_slow_down_current:
artificial_slow_down_current-=1
return
else:
poll()
else:
var t = OS.get_ticks_msec()
while OS.get_ticks_msec() < t + time_max:
var stop = poll()
if stop:
break;
artificial_slow_down_current = artificial_slow_down_frames
func poll():
var err = loader.poll()
if err == ERR_FILE_EOF:
var resource = loader.get_resource()
loader = null
set_new_scene(resource)
return true
elif err == OK:
update_progress()
return false
else:
show_error(err)
loader = null
return true
func show_error(err):
var error_str = str(err)
if errors.has(err):
error_str = errors[err] + "("+str(err)+")"
var message = "an error occured while loading the scene: " + error_str
print(message)
emit_signal("ERROR",error_str)
var errors = {
0: "OK",
1: "FAILED",
2: "ERR_UNAVAILABLE",
3: "ERR_UNCONFIGURED",
4: "ERR_UNAUTHORIZED",
5: "ERR_PARAMETER_RANGE_ERROR",
6: "ERR_OUT_OF_MEMORY",
7: "ERR_FILE_NOT_FOUND",
8: "ERR_FILE_BAD_DRIVE",
9: "ERR_FILE_BAD_PATH",
10: "ERR_FILE_NO_PERMISSION",
11: "ERR_FILE_ALREADY_IN_USE",
12: "ERR_FILE_CANT_OPEN",
13: "ERR_FILE_CANT_WRITE",
14: "ERR_FILE_CANT_READ",
15: "ERR_FILE_UNRECOGNIZED",
16: "ERR_FILE_CORRUPT",
17: "ERR_FILE_MISSING_DEPENDENCIES",
18: "ERR_FILE_EOF",
19: "ERR_CANT_OPEN",
20: "ERR_CANT_CREATE",
43: "ERR_PARSE_ERROR",
21: "ERROR_QUERY_FAILED",
22: "ERR_ALREADY_IN_USE",
23: "ERR_LOCKED",
24: "ERR_TIMEOUT",
28: "ERR_CANT_AQUIRE_RESOURCE",
30: "ERR_INVALID_DATA",
31: "ERR_INVALID_PARAMETER",
32: "ERR_ALREADY_EXISTS",
33: "ERR_DOES_NOT_EXIST",
34: "ERR_DATABASE_CANT_READ",
35: "ERR_DATABASE_CANT_WRITE",
36: "ERR_COMPILATION_FAILED",
37: "ERR_METHOD_NOT_FOUND",
38: "ERR_LINK_FAILED",
39: "ERR_SCRIPT_FAILED",
40: "ERR_CYCLIC_LINK",
44: "ERR_BUSY",
46: "ERR_HELP",
47: "ERR_BUG",
49: "ERR_WTF"
}extends Node2D
onready var button = get_node("Button")
onready var Text = get_node("Label")
onready var dir = self.get_script().get_path().replace("usage.gd","")
onready var Loader = preload("scene_loader.gd").instance(self)
var scene_to_load_path = "example_scene.xml"
func _ready():
print(dir)
Loader.connect("DONE",self,"on_loaded")
Loader.connect("PROGRESS",self,"on_progress")
Loader.connect("ERROR",self,"on_error")
Loader.slow_down() # this is so the loading process can be seen
button.connect("pressed",self,"on_button_press")
func on_button_press():
button.set_disabled(true)
Loader.load_scene(dir+scene_to_load_path)
func on_loaded(scene):
add_child(scene)
func on_progress(percent):
Text.set_text(str(percent*100)+'%')
func on_error(err):
pass