Added Glitch Room Source code to Gitty

tests/test_pixel_render.gd

@@ -0,0 +1,25 @@
+extends SceneTree
+func _initialize() -> void:
+	call_deferred("run")
+func run() -> void:
+	var game = load("res://games/galaga/Galaga.tscn").instantiate()
+	root.add_child(game)
+	game.set_physics_process(false)
+	game.state="playing"
+	game.player.position=Vector2(112.1,256.1)
+	await process_frame
+	await process_frame
+	await RenderingServer.frame_post_draw
+	var first := root.get_texture().get_image().get_data()
+	game.player.position=Vector2(112.4,256.4)
+	await process_frame
+	await process_frame
+	await RenderingServer.frame_post_draw
+	assert(first==root.get_texture().get_image().get_data(),"Fractional positions within the same native pixel must render identically")
+	game.player.position=Vector2(112.7,256.7)
+	await process_frame
+	await process_frame
+	await RenderingServer.frame_post_draw
+	assert(first!=root.get_texture().get_image().get_data(),"Crossing a native pixel boundary must move the rendered sprite")
+	print("NATIVE PIXEL RENDER TEST PASS")
+	quit()