Advanced Feature Creation: Point at offset

KGJames

Mike,

I'm having trouble using this feature. Is it me, or is it a bug?

Using GM14 - b091212, UK Grid. If I enter 2 points, 130km or so apart, measure the range & true bearing from one to the other, and use the Advance Feature Creation to create a new point at the measured range and bearing, I get a 3rd point offset in bearing by several degrees and a hundred metres or so from point #2. If I create a new line from point #1 using the Range/Bearing/COGO facility, it ends at point #2, as it should.

Here are points #1 & #2

74915,871677
96820,740140

Measured #1 to #2 as
Seg Len: 133.24 km, Seg Brg: 165° 58' 17.7", Total Len: 133.24 km

Range and bearing to newly created point
Seg Len: 133.14 km, Seg Brg: 160° 25' 31.2", Total Len: 133.14 km

Regards
Ken

global_mapper

Ken,

That's a quirk of how the point offset works. It always does a grid bearing/distance, whereas the distance/bearing/COGO and measure tool default to great circle bearing/distance (you can change to grid or even rhumb though if you want). If you switch the others to do grid distance/bearing then the results would match, but there currently isn't a way to get the point offset to use anything other than grid offset since the other options on the dialog (i.e. fixed XY offset) are always in terms of grid coordinate values.

Thanks,

Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com

KGJames

Mmm. Thanks, I think!