Three related editor fixes surfaced while debugging a captured house
project that rendered an infinite wall and failed to load.
Infinite wall (core/systems/wall/wall-mitering.ts):
Junction miters are line-line intersections, so the joint point sits
~halfThickness/sin(theta) from the junction. The only guard was an
exact-parallel check (det < 1e-9), so two walls meeting at a shallow
angle (a room-preset preview dragged onto an existing wall, or a wall
drawn nearly collinear to its neighbour) produced a joint point far
away — an infinite spike. Add a miter limit: reject joints farther
than 10x half-thickness from the junction and fall back to a square
joint, exactly like the parallel case.
Scene load failure (core/utils/heal-scene-graph.ts + validate-build-json
+ use-scene migrateNodes):
Capture wall-merge could leave a `children: [null]` entry (see the
matching merge-walls.ts fix in private-editor) and zero-length walls.
`null` children fail wall schema validation, so the whole scene fails
to load. Add a shared heal step — strip non-string child refs, drop
childless zero-length walls — run on every load path: import
validation now repairs instead of hard-failing (with a warning), and
setScene heals on the prod project-load path too.
Grid snap (nodes slab/ceiling/spawn tools):
These tools hardcoded a 0.5 m snap (Math.round(x*2)/2) and ignored the
editor's grid-snap setting, so the cursor jumped by 0.5 while later
vertices already followed the configured step. Route them through
snapPointToGrid / snapScalar with gridSnapStep.
Adds unit tests for the miter limit and the heal step.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
