internal/packing/packing.go
func square(width, height int) float64 {
	if width == 0 && height == 0 {
		return 0
	}
	if width <= height {
		return float64(width) / float64(height)
	}
	return float64(height) / float64(width)
}
func square(width, height int) float64 {
	if width == 0 && height == 0 {
		return 0
	}
	if width <= height {
		return float64(width) / float64(height)
	}
	return float64(height) / float64(width)
}
// square returns a float value indicating how much the given rectangle is close to a square.
// If the given rectangle is square, this return 1 (maximum value).
// Otherwise, this returns a value in [0, 1).