So d3's concept of scaling is making my head explode. That aside, I seem to be thudding my head against the wall in trying to use a projection. Or rather, to set one up.

I have a map. It's not an Earth map, but it's at a 2:1 ratio and thus directly mapable at a x,y => lat,lon function with scaling factor.

D3 provides a Equirectangular projection, (d3.geoEquirectangular), but when invoked, it constructs a projection such that lat/long 0,0 = 480,250. Which would be a 1.92:1 ratio, rather than 2:1.

Am i missing something? Why is the projection at this ratio? Can the ratio be fixed by some magical command that none of the documentation details?