The merged face count no longer joins faces across a Split Face line, and Offset Face's same-surface grouping stops there. A piece whose move the body's topology cannot follow (its neighbour stays put) is swept along its normal and joined on or cut in, giving walls along the split line as in Fusion. Engine test: a split box top counts 7 faces; one half up 5 (27000 mm³), the other down 3 (25200 mm³).
Fixes#12
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RjGw4gA5ZvKrU8MQP6sBgT
Split Face records the new edges as polylines on the body (Body::split_lines); the document carries them through later features. STEP export no longer joins pieces of one surface across such a line, and healing (fillets, chamfers, booleans, shell, draft) no longer merges coplanar pieces there, while incidental pieces (boolean leftovers, seam halves) still merge as before. Tests: plane and cylinder splits keep their face count through a STEP round trip (and join without the record), a second split keeps both lines, and an engine test exports a split box after a fillet with 8 faces.
Fixes#11
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RjGw4gA5ZvKrU8MQP6sBgT
Export: ExportCommand/CLI --out/MCP export with .3mf write a 3MF Core package
([Content_Types].xml, _rels/.rels, 3D/3dmodel.model; millimetres), one
mesh object and build item per body, named after it, vertices shared and
welded watertight (T-junctions between faces split), base-material colours
when bodies carry one (STEP colours now ride on bodies). Tessellation as
for STL. File > Export 3MF.
Import: doc.open/drag-drop/CLI/MCP open accept .3mf and .stl; Insert Mesh
(ParaMeshInsertAlignCommand) adds them to a design as a MeshImport feature.
Kernel mesh bodies render, measure exactly, move and export; solid
features refuse them with a clear error. 3MF reading flattens components
and build transforms, converts units, reads colours; sizes, entries,
nesting and element counts are capped.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL
