I was just sending a PM about that sort of stuff to Anna. We use tiles of 2K max so that we can easily fit it into 2Gb. Although most of us have 4Gb+ we don't want to restrict it to cut out some of the members.

Its a chap called Monks who does the mapping. Hes very particular about things and a ME nut. So he has lots of ref maps and has overlaid them all into one giant map and is working off of that to create it in 3D. I believe its all georeffed so its physically accurate to the globe too. I'm just the dev creating the tools and stuff that might get us there. We have others who are also doing some sterling work too.

I would really strongly advise going to tiles. There comes a point where the machine cant cope with such large images easily. As soon as you go to tiles then the memory footprint drops tremendously. You can even use the graphics card processing. Things get faster and you can take the handbrake off.

BTW. Publius if you need a map in a few weeks thats very large take a peek at L3DT. It has some advantages and some disadvantages over other tools but its very easy and quick to get a large terrain out of it. I really like it but accept that it has some limitations that would have not worked well for MeDem. However it may be fine for what you need. A few weeks is a drop in the ocean for large scale high def mapping tho.