Thanks Terry. I'm not 100% sure, but with this approach I'd need my easting/northing to be in the same units as the distance. Is this correct?
My lat/long is WGS84 and my distance is in meters. Kind regards Tim Smith -----Original Message----- From: Terry McDonnell [mailto:[EMAIL PROTECTED] Sent: 29 June 2004 16:27 To: Tim Smith Subject: RE: MI-L New lat/long from distance/bearing Tim, I don't know MapX and would need repriming on C, and I'm not sure if there is a ready-made function to do this, but I would use trig to do this N ! ! w target -!-----o ! / n! / !b / L ! / !/ 90-b -o-----!-------- W w Start point You have bearing, angle b, and distance, length L Sin( b) = Opp/Hyp So Sin( b) = w / L So w = Sin( b) * L, giving you your distance West Tan( b) = Opp/Adj So Tan( b) = w / n So n = Tan( b) * w, giving you your distance North This works for bearings of < 90 deg so will need to be rethought for > 180, > 270 etc. but I'm sure you get the drift. As to whether MapX has functions to get the lat/long, given the distances N and W, I don't know, but I hope this helps Terry -----Original Message----- From: Tim Smith [mailto:[EMAIL PROTECTED] Sent: 29 June 2004 15:56 To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: RE: MI-L New lat/long from distance/bearing Hi, Thanks for people who have helped so far with this, I want to draw a line in MapX between two points. The function in MapX to do this takes two WGS-84 lat/long points. I don't have two lat/long points. I have one lat/long, an angle in degrees and a length in meters. I need to calculate the second lat/long (unless there is a MapX function that can draw a line - given a position, angle and distance). A C++ algorithm to do it would be fine. I can't believe MapX doesn't support such a calculation. Tim ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 12428
