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Protocol Stability

We should have a discussion about protocol stability at some point. Which (if any) messages should be considered "set in stone", versus "could change from release to release"? What about protocol structure in general? There's a lot to talk about here, and much to be documented. As the system matures and as there's increased heterogeneity of clients, there's going to be more of a groundswell and need for stabilization. However, maintaining stringent backwards-compatibility is really hard work that takes away from time spent working on new features. -- Rob Linden 14:56, 1 December 2006 (PST)

Can someone describe the file format used for animation in SL, and how it compares to and differs from the bvh format? --Eddy Stryker 07:28, 10 January 2007 (PST)

The format uses normalized key framed quaternions stored in shorts. The format is closer to that of Poser then BVH. There format consists of a header, that tells it what morphs to set, how long the animation plays and at what priority. After that there is an array of bones with each set of positions and rotations. The position array is only used in the root prim (or you can use it to animate the HUD, course there is no default animation for the HUD so once you do, you can't get it back into the default position). Both position & rotations use 3 shorts (16 bits * 3 = 6 bytes) per entry. For quaternions, it regenerates the 4th value since the quaternion is normalized. Here are my old asset notes, since LL has release the client source there isn't much point in keeping them a secret any longer. Download Speaking of animations, I always thought limiting the users to 5 priorities (0-4) was pretty silly when you reserved a full 32 bit integer. Strife Onizuka 07:56, 13 January 2007 (PST)