Text scenery component files (.scn/.inc/.scm/.ctr) are compiled into
per-file binary twins (.scnb/.incb/.scmb/.ctrb), handled transparently
at the cParser layer: a fresh twin (mtime-checked, version-matched) is
replayed instead of re-tokenizing text; otherwise the text is parsed and
a twin is compiled alongside it for next time.
Format details:
- per-file string interning: keywords/paths stored once, referenced by
varint index (so node/endmodel/... are not repeated as text)
- numeric tokens stored as 8-byte IEEE doubles, not ASCII
- includes kept as references with parameters; random sets stored verbatim
and re-evaluated on every load (choice not frozen at compile time)
- twin writing offloaded to a bounded thread pool so baking overlaps
scene construction instead of blocking the load
The legacy terrain-only .sbt path is removed; terrain now loads as
ordinary scenery content.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
