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UTM zone mismatch

Posted: 29 Aug 2016 14:51
by Blu3wolf
Im not sure it makes much difference, but TransDEM identifies the area I am mapping around Forrestfield as being in 50H, whereas I am fairly certain it is 50J (at least according to our GPS' units and to Google Earth). Other than the zone mismatch though, the grid references match up. Possible bug in the DEM? or the software?

As an unrelated suggestion, might it be possible to request a setting for a future version, for the simple vector editor - to make it possible to lock translation of an entire polyline, unless some modifier key is depressed (such as Shift)?

Re: UTM zone mismatch

Posted: 29 Aug 2016 17:53
by geophil
I am not quite sure but I guess that TransDEM is taking the south west corner of its current world to determine the UTM latitude zone letter. The current world is set by the bounding box of currently loaded DEM and raster maps. I checked for a small area of Perth and get 50J as expected.

It's not a problem, though. Whether it is H or J will not change any coordinates. Latitude zone only matters to identify northern (N and above) or southern (M and below) hemisphere, further subdivision is just a reading aid.
Blu3wolf wrote:As an unrelated suggestion, might it be possible to request a setting for a future version, for the simple vector editor - to make it possible to lock translation of an entire polyline, unless some modifier key is depressed (such as Shift)?
Note taken, added to the todo list. I had never thought about any remedy, but accidental translation (the mathematical term for move :D) happens to me quite often as well. You can use "undo", of course, but this also deselects.

Re: UTM zone mismatch

Posted: 06 Oct 2016 18:42
by geophil
Blu3wolf wrote:As an unrelated suggestion, might it be possible to request a setting for a future version, for the simple vector editor - to make it possible to lock translation of an entire polyline, unless some modifier key is depressed (such as Shift)?
Implemented. Press Shift to move the polyline(s) in upcoming 2.6.1. It's an option but "on" will be the default.