pir-serious-game-ethics/addons/transit/Transit.gd

extends Control

signal scene_changed

const DEFAULT_DURATION := 0.2
const DEFAULT_DELAY := 0.0

onready var _animator := $AnimationPlayer
onready var _curtain := $CanvasLayer/ColorRect

func set_color(color: Color):
    color.a = _curtain.color.a
    _curtain.color = color

func change_scene(path: String, duration: float = DEFAULT_DURATION, delay: float = DEFAULT_DELAY):
    if duration <= 0.0:
        push_error("TRANSIT ERROR: change_scene duration must be > 0. Defaulting to %s" % DEFAULT_DURATION)
        duration = DEFAULT_DURATION

    if delay < 0.0:
        push_error("TRANSIT ERROR: change_scene delay must be >= 0. Defaulting to %s" % DEFAULT_DELAY)
        delay = DEFAULT_DELAY

    # disable mouse interaction while fading out
    _curtain.mouse_filter = MOUSE_FILTER_STOP

    if delay > 0:
        yield(get_tree().create_timer(delay), "timeout")

    _animator.playback_speed = 1.0 / duration
    _animator.play("fade")
    yield(_animator, "animation_finished")

    var err := get_tree().change_scene(path)
    if err:
        push_error("TRANSIT ERROR: Failed to change scene to %s: %s" % [path, err])

    # re-enable mouse interaction before fading back in
    _curtain.mouse_filter = MOUSE_FILTER_IGNORE

    _animator.play_backwards("fade")
    yield(_animator, "animation_finished")

    emit_signal("scene_changed")