Horizontal guide lines while creating LineStrips[Feature]

[metobom]

I am trying to create symmetric line strips for lane detection. For example if there is a dot in (x0, 250) in left lane, there must be a dot in (x1, 250) too. After creating a line strip in left it is hard to create another line strip symmetric to it in right. A horizontal guide line would make everything easier.

Example image:

I stroll around local files but could not figure how to do it. I think this would be a good feature. Any help to achieve this?