Draw multiple sprites with 1 GameObject

Ok so I managed to make an editor script based on tutorials in the internet for a custom object that is supposed to represent ground as a polygon. Basically an in editor polygon editor that lets me define points. Now I want to avoid having hundreds of GameObjects just to draw ground on that polygon shape so that my game won't run like 5 fps on a mobile device. Here's the deal. Lets say I have this terrible drawing to represent my ground

Now I define 2 points in Editor Scene view like this so they define a line:

And what I want NOW is to have this 1 object draw sprites across this line like this: (sorry, only 2 attachments allowed so this will have to be a link)

Click

Please don't send me to Asset Store for this, I want to do it myself and learn.