Mapping Hacks

28

|

Chapter 1, Mapping Your Life

#8 Publish Maps of Your Photos on the Web

HACK

Figure 1-16 shows some trips that are common in my life. The direct dis-

tance is the straight-line distance between the two points. Mapquest Dis-

tance is the distance reported by MapQuest. Detour Index is calculated as

shown earlier. The table also shows the estimated time and the average

speed for this trip.

Here we can compare the straight-line distance with the routed distance.

Highway 17 over the Santa Cruz Mountains is notoriously curvy. The other

numbers yield few surprises. Sacramento to Bakersfield was a ringer! That

trip is almost straight down Interstate 5. It has the lowest Detour Index of

any of the sample routes.

An awful example of curvy driving is the route from Willits, on highway

101, to Fort Bragg. That section has a 147% distance premium, compared

with the straight-line distance.

Assuming these relationships hold true, I can assert that a Detour Index

greater than 120 is almost guaranteed to make you sick! I wish to avoid the

curvy routes, but some folks like curves, so another use of this technique is

to find the curviest possible roads for motorcycle fun. Just remember: for

some people, motion sickness is no laughing matter. For the rest of us, it is.

More Information

“How Far Is It” is the creation of Darrell Kindred. It uses the geod program

from the PROJ system discussed in much more detail in