Start with a polar map projection and draw your continent. Then use a piece of software to reproject it to your desired projection. I recall hearing that G.Projector wants an Equirectangular projection input, so you'll need something to go from your polar projection to Equirectangular. Many years ago I wrote a Windows program called ReprojectImage ( http://www.fracterra.com/ReprojectImage.zip ) that can go from various projections to Equirectangular, but it's a little twitchy.