Thought Process of Working in Google Maps

Sometimes as a front-end you think by taking the “back-end” methodology route, you can accomplish great feats. In the end, the answer is often much simpler than you think. Such as in this example.

I need to find the coordinates of the center of a polygon.

Easy right?

First problem, the polygon is stored in KML format in a Fusion Table. Let’s use my awesome getJSON call from last year to retrieve the data, oh wait, the API has changed, okay let’s go to their ajax example even though it’s technically equivalent. Now the data is an object, oh I can’t work with an object.

Google, google, google…

Let’s try Google visualization since they enjoy offering different ways to find the same carrot. Oh okay I have to load Goog JS. More resources, the better! A dozen for loop iterations later, I still have an object.

Okay let’s try stringifying by manually pulling out the coordinate information from the KML object with js splits, parseFloats and jQ text() conversions. Great now I have 20 lines of coordinate data because it’s a complex polygon.

Except to retrieve the bounds of the polygon, I need a RECTANGLE. Argh! Perhaps if I become a zen master of algorithms, I can determine which four lines of coordinates are the approximate four corners of an averaged rectangle. Easy!

Google, google, google…

Try getCenter, getBounds and anything that gets something out of nothing. Thinking I need to extract the raw KML formatted data as is and then use to to call forth KmlLayer inline. Half an hour later, I realize I’m trying to thrust a packet of data into what is only a URL call.

Maybe I should extract the first coordinate point of each polygon via strlens and use that as an approximated marker location with some math adjustments. Oh wait, every polygon’s first coordinate point is all over the place. Banish the thought.

Google, google, google…

Answering some random questions on StackOverflow that do not relate but came up anyway.

Upon consulting every inch of Google Maps V3 developer guide, I come to realize I just need to zero in on the infoWindow’s self-centered latLng itself.

Several hours and dozens of lines of test code later, I actually needed just one line of code.

Yes sir, you can have labels in the middle of each polygon now.

/die.

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