First off, I'd say the limit is really the coordinate system you use. Assuming you have a 4-byte integer value measuring meters, then you already can go roughly 2.000.000.000 meters in any direction, which well exceeds terrestial distances, but isn't quite enough to take you from the Sun to Pluto (iirc, my numbers may be wrong). That is why Java3D for example has a 256-bit HiResCoord data type, which "is sufficient to describe a universe in excess of several billion light years across, yet still define objects smaller than a proton." If that is still not enough, you could use an arbitrary number of bits, which is theoretically limitless. In practice it will be restricted by the amount of bits supplied by your main memory, though :-)
However, people do not like to work with large numbers. It is much more convenient to have the coordinates of your world closely around (0,0,0). You have that in your pyramid world, and the little penguin will want it for its iceberg too, probably on the spot where he keeps his bucket of fish. Then you *link* the iceberg into your pyramid world, just like a web hyperlink, but with attached coordinates: It states that the iceberg is at (x,y,z) in your pyramid coordinate system. The peguin does the same for its iceberg world, indicating where the pyramid is located in relation to its fish bucket. These two numbers should be inverses of each other if you want realism, but they don't have to be; it could be much closer from the iceberg to the pyramid than vice versa, or not possible at all to go in one direction. This kind of free linking is just one possibility however; some people may prefer a fixed sized grid for this sort of thing, or a more restricted scheme for who may link to what. In any case, there should be some halfway point at which the seagulls stop using the pyramid server for position tracking and switch over to to the iceberg server. This kind of handover is more or less what you do to make cellphones work. Hope this helps a bit! Karsten Otto (kao) _______________________________________________ vos-d mailing list [email protected] http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
