His blog post explains a few of the specific problems he encountered while creating it:
- "The most basic issue with implementing this is geocoding all of the location strings (like "Canal & Broadway") to a latitude/longitude pair... It is not perfect, but since the set of addresses is pretty tightly constrained, I was able to add some rewriting rules to make the input more easily parsed. As of right now, 54% of the addresses are geocoded."
- "I didn't want to directly scrape the HTML of the site to extract all of the quotes. I ended up using the data stored in Google Reader's archive of the site's feed. This allowed me to get at the quotes themselves more easily, without having to worry about the chrome of the site."
- "Instead of each marker being its own overlay, I put all of them in the same overlay (see the
QuotesOverlayclass). Additionally, I did not split each marker into several layers (shadow, image, click area) - having the shadow be part of the image works well enough."