Can't generate map across dateline

[jlev]

I'm trying to generate a pacific-centered map using the lonlat projection (lon0 = 160), but the output ends up with the standard bounds [-180, -90, 180, 90], like so:

Specifying alternate bounds like [-340, -90, -20, 90], gives the correct image for everything east of the dateline, but cuts off everything to the west.

What I want seems to be possible with the Visual Configurator, which doesn't specify bounds just a lon0 value. Looking at the javascript globeopt does include an offsetx that doesn't appear anywhere in the python code.

If I don't specify any bounds but include graticules or the sea layer, I get the errors mentioned in #107. I tried to fix that with a minor patch to kartograph/map.py#L256 adding

if (layer.source.__class__.__name__ in ['GraticuleLayer', 'SeaLayer']):
    return []

However, that causes a KartographError "'no features found for calculating the map bounds'".

I also tried specifying points at the desired corners of the map, but that causes the resulting bounding box to be the minimum area between them. Is there any way to specify that I want the bounding box to be computed the "long way round?"