extends TestCase
## The helpers that every style draws with.


func test_a_point_can_be_found_along_a_path() -> void:
	var path := PackedVector2Array([Vector2(0, 0), Vector2(10, 0), Vector2(10, 10)])
	check_eq(ArtStyle.along(path, 0.0), Vector2(0, 0), "the start")
	check_eq(ArtStyle.along(path, 0.5), Vector2(10, 0), "halfway is the bend")
	check_eq(ArtStyle.along(path, 0.75), Vector2(10, 5), "three quarters")
	check_eq(ArtStyle.along(path, 1.0), Vector2(10, 10), "the end")
	check_eq(ArtStyle.along(path, 2.0), Vector2(10, 10), "never beyond the end")


func test_shares_lie_between_zero_and_one_and_stay_the_same() -> void:
	for variant in [0, 1, 99, 123456, 2147483647]:
		for salt in 4:
			var share := ArtStyle.share(variant, salt)
			check(share >= 0.0 and share < 1.0, "share of %d and %d: %f" % [variant, salt, share])
			check_eq(ArtStyle.share(variant, salt), share, "the same again")


func test_a_sway_swings_gently_and_differs_between_things() -> void:
	for tenth in 100:
		var swing := ArtStyle.sway(tenth * 0.1, 7)
		check(swing >= -1.0 and swing <= 1.0, "between left and right at %.1f s: %f" % [tenth * 0.1, swing])
	check(ArtStyle.sway(0.0, 1) != ArtStyle.sway(0.0, 2), "two things do not swing alike")