Saturday, April 5, 2008
The New Design: Core and Floor Architecture for Second Life Using Huge Prims
The arrival of Havok 4 is about to create a revolution in second life design. Many treasured buildings are now obsolete, and could be rebuilt on a fraction of the prims, with much greater usability. The new design of Second Life, which will be replicated hundreds of times, is "Core and Floor."
In Havok 1 Huge prim hollow was largely for looks, though certain cut and hollow combinations worked. The problem was that the bounding box of even simple huge prims was calculated on the outside and outside alone. There were tricks that could get around this, for example a button that phantomized a huge prim long enough to enter the bounding box, and the solidified it. However, every so often, the huge prim might expel avatars inside.
In Havok 4, huge prim bounding boxes are calculated correctly. Sidewinder Linden responded to a bug which broke complex huge prims, to keep the features of hollowed huge prims correct. The combination of a hole in a floor prim, with a spiral allows floors to be built with a spiral through the middle. By stacking huge prim spiral/floor combinations, it is possible to build, on about 10 prims per floor, a tower of any height up to 1024M. I am sure this is being done, or will be done shortly, since 200 prims will build a tower to the new 1024 limit, which means that it could be usably occupied even in an open space sim.
The first part of the core and floor design is, of course, the use of a huge prim floor with a hollow. The simplest is a 256 prim that covers an entire sim, with a round hole in the center. This is accomplished by selecting hollow, and then selecting the shape to be round. The tube, torus, or ring will be put through this hole.
The second part of the core and floor design is the use of a torus, tube, or ring. This is best set to 4 revolutions, however other sizes can be used. The spirals are then stacked on top of each other. Without a gap they form a smooth ascending stair case. With H1, this was often done with 10x10 prims, but these could be hard to navigate. With the 32x32x40, 40x40x40, 50x50x50 the result is a large walk area which is even sufficient to have usable space inside of it. Think the shape of the Guggenheim Museum.
The third technique that completes the Core and Floor is the use of the "Gap." The gap is when, instead of joining the entrance of the next spiral to the exit of the previous spiral, the top of the old spiral is used as a walk way. The entrance to the next level is rotated 180 degrees, creating a gap. This gap can be protected by creating a huge prim "rail." The huge prim rail is cut to a very thin profile, and shortened using path cut. These thin rails are visible in the illustration provided.
To construct a simple core and floor system, all that is needed is to build the first floor and core, adjust the position of the next floor and then grab an example of the floor and core paring as a coalesced object. This object is then put inside a huge prim rezzer. These can be constructed with relative ease, or purchased. The height between them is set, and the number of floors is set. The huge prim rezzer warposes to the next heigh, rezes, waits because a large rez uses "energy," and then warposes to the next location. The result is a tower in less than a minute to any buildable heeght.
More architecturally distinct core and floor designs can be made, using several huge prims for each floor. In this case a harness prim or prims are often needed, which is simply a single huge prim with a circular hollow.
In summary, under Havok 4, huge prims make practical and easy the building of an architectural style based on hollowed floor prims with hollowed complex spirals as the walk way between them. The simplest version takes up only a few prims per floor, and can be easily rezzed using a warpos driven rezzer.
The example building show is at Yedo Bashi,and was built in only two hours of working time. It uses less than 100 prims, and has two 256 levels, three office levels and an observation deck. It is, at 312M high, as tall as the old Eiffel Tower was. It is possible in an openspace™(Linden Labs) to walk around comfortably with render far clip at 512M.