You guys are all making incorrect assumptions of how textures are used in games. The textures in MS CFS III (and definitely those before) are not specifically based on imaging of the Earth. Using a Blue-Marble type texture, for instance, would be
very inefficient for the requirements of a game.
The textures are most definitely
small-ish squares that represent
types of terrain. There's a grass texture, a sand texture, a water texture, a pavement texture, etc. These textures are tiled, one on top of another, to build up the look of the terrain in the game. The size of the textures is chosen to optimize the use of the video card's memory. Current games are probably not using textures larger than 512x512.
The actual geometry of the landscape is probably derived from some real elevation data but not likely at a very high resolution. The high detail seen in-game is interpolated from the real samples to make it look good.
The accuracy of the visuals in flight sims is not constant. More resources are spent trying to get the layout of cities and famous landmarks as close to real as possible. The rest of the terrain is just classified as fields or deserts or ocean. The textures for those areas are stitched together in such a way as to be most aesthetically pleasing.
Celestia doesn't work this way and I don't think it's the direction that Chris wants to go. Least of all, it would make creating textures for planets much more complicated as you would not only have to create the "component" textures, but then specify how they're stitched together. Not feasable.
EarthViewer, Don, does not store the textures on the client machine. You need an internet connection to use the program because the very high resolution images are downloaded as needed. They probably have
terabytes of near-military grade textures in their database, but you only get the data for a city at a time.
Star Lion, I have no clue what you're talking about...
- a b i o g e n e s i s -