How to modify the size of the icons in the launcher and the size of the launcher itself in the code?

As the title implies I would like to tweak the size of the icon in the launcher (it looks to big to me vs the other elements in my desktop environment), can you point me to try right spot in the code where I could do it. Also where in the code I could modify the dimensions of the launcher itself?

Can I do it without recompiling? Is there some config file somewhere where I could modify that.
Running Ubuntu 16.04.

Thank you!