The band filled the mouth because a band is the wrong reduction: the bright
region is a blob, and reading it as "everything above a line" throws the shape
away.
Extracting a contour reintroduces the vertex-correspondence problem that made
me avoid it, but for a blob there is a way out. Radial sampling from the
centroid along N fixed directions makes vertex k always mean "the extent in
direction k": correspondence holds by construction, the count is fixed, and
temporal smoothing cannot reorder anything. It also yields a star-shaped
reduction, which suits flat colour.
Tongue rejection, which the band had no way to express:
- pixels red relative to their own brightness are dropped (teeth are neutral)
- component choice is biased toward the top of the cavity, since area alone
picks the tongue when the mouth is wide
- separate inner and outer controls: cavity erode pulls the sampled region off
the lip edge, blob grow/erode resizes the found blob
Also: a knob wired in app.js but missing from index.html threw during wiring
and left a blank page with nothing useful in the console - which is exactly
what happened to teethDwell in the previous commit. el() now names the missing
id, and window.onerror surfaces it in the status line.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Your Name
9a11eeabc1