Avoid the Sun Walking Directions

If even the mere thought of walking in the midday sun gives you sweaty palms then you need the new Parasol walking directions map. Parasol is a routing engine for Boston which can give you walking directions between any two points in the city, optimized for walking in the shade. If you love the sun then don't worry. Parasol isn't just for those looking for shade, it can also be used to find you a route that avoids the shade and maximizes your time in the sun.

Using Parasol you can ask for walking directions in Boston and get directions based on how much sun or shade you prefer. You just need to enter two locations into the map, adjust a slide control to enter the level of sun/shade you require and enter the time of day when you will be walking. Parasol will then show you your route based on the level of sun/shade that you requested.

Parasol uses lidar data to work out the location and the height of buildings and trees and other objects that provide shade in Boston. It then uses that data to calculate the position of the shadows cast by those objects depending on the position of the sun. A cost function that incorporates the level of sun/shade is then calculated and the shortest path between two points is mapped out given this custom cost. You can learn more about how this is implemented and what tools were used in the author's blog post on Parasol.