all the things

World/Main.tscn

@@ -1,7 +1,7 @@
 [gd_scene load_steps=2 format=2]
 
-[ext_resource path="res://World/Tree.tscn" type="PackedScene" id=1]
+[ext_resource path="res://World/Plant.tscn" type="PackedScene" id=1]
 
 [node name="Main" type="Node2D"]
 
-[node name="Tree" parent="." instance=ExtResource( 1 )]
+[node name="Plant" parent="." instance=ExtResource( 1 )]

World/Pixel.gd

@@ -0,0 +1,8 @@
+extends ColorRect
+var empty = true
+var position = Vector2()
+
+export var lighter_green = Color("#91e369")
+export var light_green = Color("#56c157")
+export var medium_green = Color("#46a65c")
+export var dark_green = Color("#358859")

World/Pixel.tscn

@@ -1,9 +1,11 @@
-[gd_scene format=2]
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://World/Pixel.gd" type="Script" id=1]
 
 [node name="Pixel" type="ColorRect"]
 margin_right = 1.0
 margin_bottom = 1.0
-color = Color( 0, 0, 0, 0 )
+script = ExtResource( 1 )
 __meta__ = {
 "_edit_use_anchors_": false
 }

World/Plant.gd

@@ -1,23 +1,31 @@
 extends Node2D
 export var size = Vector2(128, 144)
 # 2 dimensional array y and x
-var pixels_y = []
+var pixels_x = []
 
 func _ready():
 	call_deferred("spawn_pixels")
+	call_deferred("plant_seed")
 
 func spawn_pixels():
 	for n in size.x:
-		var pixels_x = []
+		var pixels_y = []
 		for i in size.y:
 			var Main = get_tree().current_scene
 			var Pixel = preload("res://World/Pixel.tscn")
 			var pixel = Pixel.instance()
 			# set position
 			pixel.rect_global_position = Vector2(n, i)
+			pixel.position = Vector2(n, i)
 			# show in scene
 			Main.add_child(pixel)
 			# initilize array
 			pixels_y.append(pixel)
 		pixels_x.append(pixels_y)
 
+func plant_seed():
+	var rect = pixels_x[size.x / 2][size.y - 8]
+	rect.color = rect.light_green
+
+func grow():
+	pass

World/Plant.tscn

@@ -0,0 +1,12 @@
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://World/Plant.gd" type="Script" id=2]
+
+[node name="Plant" type="Node2D"]
+script = ExtResource( 2 )
+
+[node name="Timer" type="Timer" parent="."]
+wait_time = 0.25
+autostart = true
+
+[connection signal="timeout" from="Timer" to="." method="grow"]

World/Tree.tscn

@@ -1,6 +0,0 @@
-[gd_scene load_steps=2 format=2]
-
-[ext_resource path="res://World/Tree.gd" type="Script" id=2]
-
-[node name="Tree" type="Node2D"]
-script = ExtResource( 2 )