Hello Davide
It should be possible with customizing the code of the google maps module. However, honestly, this is out of scope of our support (I don't know how to do it yet, just look like it is possible using Google Map API), so we could not implement it for you (for free)
If you really need it, I guess some customization will be needed and it will cost you about 40$ - 50$ for the customization
Not sure if it is worth to invest that amount of money into the module, thought
Tuan
