- From: Angel Machín <angel.machin@gmail.com>
- Date: Mon, 13 Oct 2008 14:38:55 +0100
- To: public-geolocation@w3.org
- Message-ID: <5562f69c0810130638t17323074m2b96f8382f3c57b7@mail.gmail.com>
Hi Mathew, Yes, it could be convenient to have this additional variable that together with the heading could be used to calculate a 3D vector corresponding with the device's orientation. It could be easily read from the device's accelerometers if available. As an example, it could be useful for an hypotethical sky-map application. However, I think that in navigation and astronomy the right term for this value would be *elevation angle* or *altitude*. If you take the Horizontal Coordinate System that uses the observer's horizon as the reference plane, the altitude gives you this value. So when altitude is 0 degrees, you are pointing towards the horizon while with an altitude of 90 degrees you are pointing the zenith ( http://en.wikipedia.org/wiki/Horizontal_coordinate_system) The declination is used in the equatorial coordinate system which is 2D, and uses a projection of the earth as the fundamental plane. So declination in this system would be equivalent to the latitude. Thanks for posting, regards, Angel
Received on Monday, 13 October 2008 15:01:55 UTC