fix extend seems broken for some geoJson

[lpas]

const MINIMAP_PADDING = 40 // should be smaller than SIZE/2
const SIZE = 200 // actual size is size - padding
const poly = {
    "type": "Feature",
    "properties": {},
    "geometry": {
        "type": "Polygon",
        "coordinates": [
            [
                [13.056508703137666,52.362012953186536],
                [13.055221242810262,52.36091224014757],
                [13.057088060284428,52.36012599975746],
                [13.058139486218977,52.36137087391279],
                [13.056508703137666,52.362012953186536]
            ]
        ]
    }
} 
const fc = { 'type': 'FeatureCollection', 'features': [poly] }
const projection = geoMercator().fitExtent([[MINIMAP_PADDING, MINIMAP_PADDING], [SIZE - MINIMAP_PADDING, SIZE - MINIMAP_PADDING]], fc)
const geoGenerator = geoPath().projection(projection)

results in a projection with scale 19.098593171019434 and translate of  [100, 99.99999999997485]

if i now get the path and display the poly with something like

const geoGenerator = geoPath().projection(projection)
geoGenerator(fc)

i get a super small path that is barely visible

there seems to be a problem with the calculation of the bounding box of the poly but I'm not familiar enough with the lib to pinpoint where this happens. the poly seems to get clipped and this results in a to big bounding box

if i calculate the bbox with something like turf i don't have this problem. if i calculate the scale & translate myself it comes out to something like scale 2225147.3776166504 translate [-506971.1720894703, 2395335.8344671903]

[lpas]

I looked at this a little more and i guess the poly is in the wrong winding order for d3 and thus creates a big square with a little hole in it that i couldn't see (because the image was very small and i only used outline)

looks kinda strange to me but if this the intended behaviour the ticket can be closed

[Fil]

yes, see #227 ; you can probably use turf.rewind to change to winding order?