1.项目构建如下，map是我们点击start之后才渲染出来的 

mian.tscn --main.gd
--background(textureact)
--start(button) --button.gd
sourceFile
map.tscn
--tilemap --tileset

2.main.gd：注意main.gd并不定义信号，它只是接收信号而已

extends Control

# Called when the node enters the scene tree for the first time.
func _ready():
	$start.connect("game_start", self._on_start)
	pass # Replace with function body.

func _on_start():
	#var s = preload("res://map/map.tscn").instantiate()
	#add_child(s)
	get_tree().change_scene_to_file("res://map/map.tscn")

# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):
	pass

 用preload的方式会导致map和user界面重叠，两个都显示在一起了

3.start.gd

extends Button

signal game_start

# Called when the node enters the scene tree for the first time.
func _ready():
	connect("button_down", self._on_pressed);
	pass # Replace with function body.

func _on_pressed():
	emit_signal("game_start")

# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):
	pass

4.如何导入图片，导入图片的是tilemap下的tileset，tilemap是导入之后绘画的，不要搞错了

如图，右键点击【新建tileset 】之后，点击下面的【tileset1】把左边的图片拖过来，再点击右边的tilemap画图