Crafting maps for underwater worlds

The maps in Minecraft allow you to graphically represent cities and roads. But what if you're building an underwater world?
I built an entire city of glass domes in the ocean, connected by glass tunnels. I wanted to create a large map of it, but unfortunately, you can't see anything of my city on it. Neither the glass domes nor the tunnels are visible.
It would be great if you could expand the normal maps through crafting so that they also show structures in the depths of the oceans.

Thank you.