@chestnutlabs/gcode-dialects

Slicer/firmware dialect adapters for the Chestnut Labs G-code Preview stack (design: DD-005). Dialect adapters annotate a parse — features, object boundaries, bed geometry, thumbnails, multi-tool metadata — and are forbidden from changing geometry (a geometry-invariance gate enforces it).

Supported dialects: PrusaSlicer, OrcaSlicer/Bambu Studio, Cura, Klipper, Marlin, RepRap-flavor — see the evidence-dated compatibility matrix.

Every annotation is capability-tagged (known | inferred | approximated | unavailable); consumers render what is known and disclose what is not.

Slicer comments are untrusted file data. A comment whose value cannot be true is left out of the metadata. That covers a print time or filament total that overflows or is not a number (Cura ;TIME: included), a print height of zero or less, a bed outline that encloses no area, and a comment thumbnail that is malformed (dimensions outside 1..65535, over the size cap, longer than declared, not base64, or never closed). The parse records one dialect-metadata-invalid warning for these, with a count. A bed point that is not finite gives no bed, with the dialect-bed-unparsed warning. When a file carries more of something than the annotator keeps (thumbnails, object names, filament slots), the extra entries are dropped with a dialect-annotation-truncated warning. It never reports NaN or Infinity, and it never fails the parse. Filament colours may be #RRGGBB or #RRGGBBAA; the alpha is ignored.

A custom adapter gets the same treatment. Sink input that cannot be used (an object value outside 1..10,000, a tool id that is not a whole number, a colour that is not a string) is dropped with a dialect-metadata-invalid warning. If an adapter's annotations still fail to apply, none of them are kept, and the parse records adapter-failed. An adapter that reads comment thumbnails with ThumbnailCollector should call collector.close(sink) in finalize, so a block left open at the end of the file is reported instead of dropped silently.

This package is bundled into the parser's default batteries worker — most applications never import it directly. Import it to build a custom worker with a chosen adapter subset, or to register your own adapter against the annotator contract.

Part of Chestnut Labs G-code Preview · MIT