OK, where to start. Let me start with where the screenshot was taken. It was taken at Rumsey Maps, which includes a huge 3D map of Yosemite Valley, as well as a bunch of other cool examples of cartography.
Maybe I should now start at the beginning. I was researching for an upcoming blog article and came across a fact that Second Life has over 1800 square kilometers in land. (I originally thought it was around 1000, but I was looking at old statistics). There are however reports that the amount of land is dropping rapidly because of the change in open space policy.
Anyways, I got into yet another discussion about the difference between There.com and Second Life, and this land issue came up. There.com actually resides on a 3D planet sized sphere slightly smaller than planet earth. It is possibly the largest 3D object in virtual space navigable by virtual avatars. It has even been circumnavigated, taking weeks to complete. The question always comes up, how much actual land is there in There’s globe? Turns out the answer is 630 square kilometers, plus or minus 20, but I’m getting ahead of myself.
The next question usually is, how does all this compare to the real world?
It was about then that I discovered this entertaining video called A Geophysical Survey of World of Warcraft
Now this video awoken the geek in me, and all this talk about the relative land mass in There.com and Second Life, and that got me started on a pretty cool project.
The end result being this map. A scale map of Second Life, There, World of Warcraft, and Oahu:
Click picture for full size version. Its about a megabyte big, so feel free to copy and distribute it elsewhere so as not to kill my bandwidth. The relative scale is 14 pixels = 1km.
According to Linden Labs figures, the total land in Second Life is just over 1,800 sq. km. Oahu is around 1,500 sq km. So when you measure all the Second Life regions, they a little bit bigger than Oahu.
To figure out There.com land area, I took the scale map of There, selected all the water and made it black, then inverted the selection and made the land white. I went around the map making sure I did not have any stray odd pixels to mess up the calculation. I also remeasured known distances to make sure my scale was correct. I then used a histogram function to find out how many pixels were black and how many were white. Of the 14,256,222 pixels, 122,883 were white. Divide that by 196 (14×14) = 627 km sq. There is stuff in There missing from the map (Saja, Snowman Island, and Coke Island), plus possible errors to my methodology, hence the plus or minus 20 km sq. part.
In scaling all the maps, I used multiple methods as well. The second life client, used to tell you the total distance from where you are to your destination, it doesn’t anymore. But, I found a way around that by finding the “grid position” of the region I am on in the debug tools then going to a region on the far left and the far right and finding how many regions across it is and multiplying by 256 to get meters, and divide 1000 to get kilometers. The regions charted at slurl.com (which is the map I used) is 186km across and 110km top to bottom.
I did the scale work in There years ago on my web site. Two prominent dots on the map, the white mountain on Comet and the tiny island of Egypt are 225 km apart.
WoW was based on work done on this link, confirmed in the video above.
Then I needed a real world island to use as a comparison. Ireland was way too big when I scaled it, Manhattan was way too small (about the same size as WoW). The big island of Hawaii fit but covered most of the map, and then decided to use the most populated and more famous island of Oahu.
And there you have a method, as accurate as I can make it, of comparing the relative size of three prominent 3D worlds with the real world.