+ effect = case @effect
+ when :none: 0
+ when :plain: 1
+ when :outline: 2
+ when :soft_outline: 3
+ when :shadow: 4
+ when :soft_shadow: 5
+ when :outline_shadow: 6
+ when :outline_soft_shadow: 7
+ else
+ raise(RedactError, "invalid effect value - #{@effect}")
+ end
+
+ super.merge!({"effect" => [effect, :char]})