Polygon World Map Example
This time zone map is drawn dynamically and mathematically
correct using the latitude/longitude polygon data available by subscription on our
website. It demonstrates drawing of polygon borders for each time zone and
the simplicity of determining the correct time zone for a given pair of latitude
and longitude coordinates. It should be noted that these are geo-political time
zone borders and not country borders. Time zone borders take into account daylight saving
time exceptions throughout the globe. Examples of this might be Argentina with
24 independently operating zones or the US state of Indiana with 2.
To get started, just type in any address you want into the location field below...
How it works...
- This web application was written with entirely with
Intraweb from ATOZED Software
- Each of the 2600 (or so) polygons are drawn on a web
canvas to make up the map that we see in the color of their standard time
offset from UTC.
- The location that you provide is feed
thru Google and returns a set of latitude and longitude coordinates.
- The coordinates returned are then used to determine the correct
time zone polygon and the sunrise/sunset is calculated by a relatively simple math calculation.
- The correct seasonally adjusted time is then displayed from the xml file published
- A practical application for this could allow a GPS Navigation System
with automatic time zone adjustments on the move using this type of data.