Examples of org.openstreetmap.josm.data.projection.proj.Proj

org.openstreetmap.josm.data.projection.proj.Proj

A projection (in the narrow sense). Converts lat/lon the east/north and the other way around. Datum conversion, false easting / northing, origin of longitude and general scale factor is already applied when the projection is invoked. Lat/lon is not in degrees, but in radians (unlike other parts of JOSM). Additional parameters in the constructor arguments are usually still in degrees. So to avoid confusion, you can follow the convention, that coordinates in radians are called lat_rad/lon_rad or phi/lambda. East/north values are not in meters, but in meters divided by the semi major axis of the ellipsoid (earth radius). (Usually this is what you get anyway, unless you multiply by 'a' somehow implicitly or explicitly.)


    public Proj parseProjection(Map<String, String> parameters, Ellipsoid ellps) throws ProjectionConfigurationException {
        String id = parameters.get(Param.proj.key);
        if (id == null) throw new ProjectionConfigurationException(tr("Projection required (+proj=*)"));


        Proj proj =  Projections.getBaseProjection(id);
        if (proj == null) throw new ProjectionConfigurationException(tr("Unknown projection identifier: ''{0}''", id));


        ProjParameters projParams = new ProjParameters();


        projParams.ellps = ellps;


        String s;
        s = parameters.get(Param.lat_0.key);
        if (s != null) {
            projParams.lat_0 = parseAngle(s, Param.lat_0.key);
        }
        s = parameters.get(Param.lat_1.key);
        if (s != null) {
            projParams.lat_1 = parseAngle(s, Param.lat_1.key);
        }
        s = parameters.get(Param.lat_2.key);
        if (s != null) {
            projParams.lat_2 = parseAngle(s, Param.lat_2.key);
        }
        proj.initialize(projParams);
        return proj;
    }

Examples of org.openstreetmap.josm.data.projection.proj.Proj

Related Classes of org.openstreetmap.josm.data.projection.proj.Proj