extends SceneTree
const EffectPlayer = preload("res://fx/effect_player.gd")
var failures := 0
func check(ok: bool, label: String) -> void:
	if not ok:
		failures += 1
		printerr("FAIL: " + label)
func _init() -> void:
	call_deferred("run")
func run() -> void:
	var image := Image.create(2, 2, false, Image.FORMAT_RGBA8)
	image.fill(Color.WHITE)
	var texture := ImageTexture.create_from_image(image)
	var fx := EffectPlayer.new()
	fx.build({"particles": [{"particle": {"BillboardType": 0, "SrcBlendType": 5, "DestBlendType": 6}}]})
	var particle_mat: StandardMaterial3D = fx._emitters[0].material_override
	# A plain white texture and a static quad isolate material face visibility.
	particle_mat.albedo_texture = texture
	var materials := [particle_mat, fx._mesh_material({"BlendingSrcType": 5, "BlendingDestType": 6}, [texture])]
	for i in materials.size():
		check(materials[i].cull_mode == BaseMaterial3D.CULL_DISABLED, "effect material %d is two-sided" % i)
		check(materials[i].depth_draw_mode == BaseMaterial3D.DEPTH_DRAW_DISABLED, "effect material %d does not write depth" % i)
		check(not materials[i].no_depth_test, "effect material %d still tests world depth" % i)
	if DisplayServer.get_name() != "headless":
		materials.append(preload("res://fx/particle_color_material.gd").build(particle_mat, 5))
		materials.append(preload("res://fx/particle_color_material.gd").build(particle_mat, 6))
		await visual(materials)
	else:
		print("SKIP: pixel checks require a rendering backend")
	fx.free()
	print("effect_surface_test: failures=%d" % failures)
	quit(1 if failures else 0)
func visual(materials: Array) -> void:
	var viewport := SubViewport.new()
	viewport.size = Vector2i(96, 96)
	viewport.own_world_3d = true
	viewport.render_target_update_mode = SubViewport.UPDATE_ALWAYS
	root.add_child(viewport)
	var environment := WorldEnvironment.new()
	environment.environment = Environment.new()
	environment.environment.background_mode = Environment.BG_COLOR
	environment.environment.background_color = Color.BLACK
	viewport.add_child(environment)
	var quad := MeshInstance3D.new()
	quad.mesh = QuadMesh.new()
	quad.mesh.size = Vector2(2, 2)
	viewport.add_child(quad)
	var camera := Camera3D.new()
	viewport.add_child(camera)
	camera.current = true
	var blocker := MeshInstance3D.new()
	blocker.mesh = BoxMesh.new()
	blocker.mesh.size = Vector3(2, 2, 0.1)
	var black := StandardMaterial3D.new()
	black.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	black.albedo_color = Color.BLACK
	blocker.material_override = black
	viewport.add_child(blocker)
	for i in materials.size():
		quad.material_override = materials[i]
		for side in [1.0, -1.0]:
			camera.position = Vector3(0, 0, side * 3.0)
			camera.look_at(Vector3.ZERO)
			blocker.visible = false
			var color: Color = await center(viewport)
			check(color.r > 0.8, "material %d side %d visible pixel=%s" % [i, int(side), color])
			blocker.position = Vector3(0, 0, side)
			blocker.visible = true
			color = await center(viewport)
			check(color.r < 0.05, "material %d side %d occluded by world" % [i, int(side)])
	viewport.queue_free()
	await process_frame
func center(viewport: SubViewport) -> Color:
	await process_frame
	await process_frame
	await RenderingServer.frame_post_draw
	return viewport.get_texture().get_image().get_pixel(48, 48)