Determine the lat lngs of markers within a polygon

Question

I have a google maps app which plots markers as it loads. One of the new requirment is to to add a Polygon overlay encompassing a selection of markers by the user. I was able to

Answer 1

I have never directly messed around with Google Maps, but you can store the points that make up the polygon and then use the Point-In-polygon Algorithm to check if a given longitude and latitude point is within a polygon or not.