Creating a road with javascript

Hi all, i have a little project im doing with draw. io
I’m trying to add a road tool that you can draw a road with. But… The problem is… I want it to have propertys were i can make it have multiple lanes and shoulders and so on and so forth.

Below is a idea of what im trying to come up with

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Any help would be much appreciated.

Here is what i currently have done with draw. io
And using built in javascript shapes that i need to modify…

As you can see i need to modify the shape to fill the color and create new lanes and so on… I just dont know were to start… Looking at the javascript file for that shape i can’t find any code that would be the propertys.