Option to use different projections inside JOSM (including adding and modifying objects)

[naoliv]

Using JOSM's default projection (EPSG:3857) add a node using this coordinate: 09°01'56.55152" S , 56°40'00.00000" W and then save the OSM file.

Inside the file we can see a node at lat='-9.03237542222' lon='-56.66666666667'

Now change the projection to By Code (EPSG) and select EPSG:4618 (SAD69).
With a new layer, add a node again at the same place 09°01'56.55152" S , 56°40'00.00000" W and then save the OSM file.

See how we have exactly the same position again: lat='-9.03237542222' lon='-56.66666666667'

Since JOSM is now working in SAD69, it should interpret my coordinates in this new projection.
ie, adding a node in SAD69 should not give the same exact result as adding a node in Mercator.

JOSM:

Build-Date:2017-01-10 18:58:33
Revision:11449
Is-Local-Build:true

Identification: JOSM/1.5 (11449 SVN pt_BR) Linux Debian GNU/Linux unstable (sid)
Memory Usage: 250 MB / 4029 MB (67 MB allocated, but free)
Java version: 1.8.0_111-8u111-b14-3-b14, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 1920x1080
Maximum Screen Size: 1920x1080
Java package: openjdk-8-jre:amd64-8u111-b14-3
Java ATK Wrapper package: libatk-wrapper-java:all-0.33.3-13
VM arguments: [-Dawt.useSystemAAFontSettings=on]

[stoecker]

You misunderstand something. JOSM uses the projection settings for display and to access imagery. It does not switch coordinate handling. JOSM always uses latitude and longitude of WGS84 as coordinates (not taking the finer details like different reference frames, crustal movement, ... into account).

I don't know if we have a feature to enter projected coordinates somewhere.

[naoliv]

Hum... :-/
May I convert this ticket to a feature request then?

[stoecker]

Sure.

[bastiK]

Replying to stoecker:

I don't know if we have a feature to enter projected coordinates somewhere.

There is a 2nd tab "East/North" in "Add Node..." dialog.

[naoliv]

Replying to bastiK:

There is a 2nd tab "East/North" in "Add Node..." dialog.

But then I will need to previously convert my coordinates into XY.

The government here publishes documents with coordinates in other projections, like ​http://www.planalto.gov.br/ccivil_03/_Ato2011-2014/2013/Dsn/Dsn13593.htm

What I would like is, if possible, to work with any another projection.

[stoecker]

Replying to naoliv:

Replying to bastiK:

There is a 2nd tab "East/North" in "Add Node..." dialog.

But then I will need to previously convert my coordinates into XY.

East/North means in JOSMs case projected coordinates. For a system like EPSG:4326 this will be latitude/longitude, exactly what you asked for.

For any other purposes you should use a coodinate conversion software. That's not the purpose of JOSM.