Thanks. I think I will use the parametric formulas for calculating the coordinates of points on a circle using increments of 1 degree. If that turns out to be too ambitious (because of the performance hit generated by the additional processing once I have calculated the 360 possible locations), I will reduce the number and see what happens.
Alex Donnini On Aug 22, 12:39 pm, Mark Murphy <[email protected]> wrote: > alexdonnini wrote: > > Mark, I am well aware that there is an infinite number of points on > > the circle at distance X from a known location. To start with, for my > > application, my plan is to find 16-64 of the locations at distance X > > from my location. That should be sufficient. > > OK, which 16-64? > > > The problem I have is that, unless I am mistaken, all GC formulas are > > of the form d = some formula using lat/lng of two locations. In my > > case, I know d and lat/lng of one location. I need to find lat/lng of > > the second location. In order to solve this kind of equation (two > > unknowns), I could use some form of estimation or some other approach. > > > Unless I am missing something obvious, I think I may need to figure > > something out using the geometry of a circle combined with some type > > of estimation. > > If you don't care which 16-64, you have one center point, a radius, and > 16-64 headings (e.g., one every 10 degrees for a total of 36). That > should be sufficient data to figure out a second point. If your > distances are small (i.e., curvature of the earth isn't a big deal), > regular geometry might suffice. There should be some orienteering or > non-GPS sailing sites out there with the formulae you need. > > -- > Mark Murphy (a Commons > Guy)http://commonsware.com|http://twitter.com/commonsguy > > Android Training in Germany, 18-22 January 2010:http://bignerdranch.com --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
