extends SceneTree
## Quick visual check for the billboard crowd: builds the generated fallback stand and
## captures two frames a moment apart (so the flipbook visibly advances) from an angle
## (so we can confirm the sprites turn to face the camera).
##
##   godot --script tools/preview_crowd.gd
## Output: tools/preview/crowd_a.png, crowd_b.png

const OUT := "res://tools/preview"


func _init() -> void:
	_run.call_deferred()


func _run() -> void:
	DirAccess.make_dir_recursive_absolute(OUT)

	var we := WorldEnvironment.new()
	var env := Environment.new()
	env.background_mode = Environment.BG_COLOR
	env.background_color = Color(0.10, 0.12, 0.16)
	we.environment = env
	root.add_child(we)

	var crowd := MultiMeshInstance3D.new()
	crowd.set_script(load("res://crowd_billboards.gd"))
	crowd.set("source_path", NodePath())     # force the generated fallback stand
	crowd.set("fallback_count", 90)
	root.add_child(crowd)

	var cam := Camera3D.new()
	cam.fov = 62.0
	cam.current = true
	root.add_child(cam)
	# Outside the ring edge, elevated, looking across the centre: the NEAR arc has its
	# back to us (facing inward), the FAR arc faces us — so this shot proves both the
	# per-segment inward facing and the front/back sheet selection.
	cam.look_at_from_position(Vector3(0.0, 16.0, 44.0), Vector3(0.0, 3.0, 0.0), Vector3.UP)

	await create_timer(0.15).timeout
	_shot("crowd_a.png")
	await create_timer(0.45).timeout          # ~4–5 clap frames later
	_shot("crowd_b.png")
	quit(0)


func _shot(name: String) -> void:
	var img := root.get_viewport().get_texture().get_image()
	if img == null:
		print("capture failed: ", name)
		return
	img.save_png(OUT + "/" + name)
	print("captured ", name, "  ", img.get_width(), "x", img.get_height())