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OpenOrienteering / mapper

OpenOrienteering Mapper is a software for creating maps for the orienteering sport.
https://www.openorienteering.org/apps/mapper/
GNU General Public License v3.0
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Map north other than magnetic north #331

Open dg0yt opened 10 years ago

dg0yt commented 10 years ago

gandym01 reported on Sourceforge [tickets:#331]:

Hi,

The implementation of Map north as always being equal to magnetic north I do not find very intuitive. Also, this arrangement means that a false value must be entered for declination whenever the printed page is not to be aligned with magnetic north.

Could magnetic north be instead defined in terms of a user editable angle subtended from Map north (Map north being defined as 90º to the base of the printed page)? The intended effect would be that magnetic north (and through it true north and grid north) is allowed to rotate relative to the page without altering the declared declination value.

Also, could the "alignment" section found in the configure grid dialogue be duplicated exactly in the georeferencing dialogue for the purpose of aligning the map?

gandym

dg0yt commented 10 years ago

It is ISOM/ISSOM which says that the "sides of the map should be parallel to the magnetic north lines."

dg0yt commented 10 years ago

Somebody posted on Sourceforge:

Hi Kai,

I should say that my main interest in this wonderful project is to use it for rogaine map preparation. AFAIK there is no standard governing this sport and on all of the Australian maps I've seen maps are aligned to grid north.

Clearly, introduction of the features I suggested would make it easier to prepare orienteering maps that do not conform to the standard and one these grounds alone you may choose not to implement them. Still, you might be inclined to leave this in the hands of the user - maybe a message box could be displayed alerting the user to their departure from the standard when magnetic north is not equal to map north?

Thanks, gandym

dg0yt commented 10 years ago

Somebody posted on Sourceforge:

Swedish "ISOM" (Yes, its not just translated it is also changed a bit...) says "Kartramen orienteras alltid efter Rikets Nät, vilket innebär att meridianerna kommer att placeras snett mot kartans orientering."

That means "The map frame sould alwyas adjust to 'Reference Net of Sweden', which means the north lines always will tilt compared to the orientation of the map."

//Zerbembasqwibo

dg0yt commented 10 years ago