7.1.Principle
- Every construct only places, scales in time, offsets, mirrors, holds or fills, or references keyframes of the existing P and its hyper conditions (§3.4). No construct adds a latent dimension, changes the registry (§4), or redefines a dimension.
- Composition is compose-time. A script is evaluated once into ordinary keyframes (plus expression references, §7.6.7), and the result decodes like any other P data. A consumer that only decodes P never needs to parse a script.
- The script is the authored source. A producer SHOULD store it with the composed result so that the result can be re-composed when a source gloss or function changes.
Terms used in this section:
| Term | Meaning |
|---|---|
| Lexicon | The producer's store of named glosses, expressions, and user functions. |
| Gloss | A named run of P keyframes (one sign). Its native length is its last keyframe index (1 if that is 0). |
| Subgroup | A group split by side where the group is sided: a_l a_r w_l w_r g_l g_r h b f m. A gloss drives a subgroup when it has at least one keyframe on it. |
| Gloss flags | Lexicon flags read by the grammar: draft (unfinished), spelling (a fingerspelling letter), fixed_position (body-anchored; never shifted or anchored), left_dominant (the left hand leads). |
| Neutral pose | The rest pose configured for the composition. Where none is configured, the registry defaults (§4). |
| Frame | One step of the composition timeline. All pause, gap and ramp values are in frames. |