The wordmark segmentation mapped alpha with smoothstep(46, 120) over distance
from the background colour. That ceiling is fixed, but the ink distance is not:
white text on a black band sits at ~438, so every edge pixel brighter than about
27% grey saturated to fully opaque. A hard threshold wearing a smoothstep's
clothing. Measured on Camping in Alaska's "Needlemouth" cover, the extracted
mask's edges transitioned over 0.10px against the source's 0.88px -- nine times
harder than the artwork it came from.
The ramp's top now tracks the measured ink distance (95th percentile of
distance-from-background, so it reads the glyph body rather than the brightest
speck), with the old constant kept as a floor so low-contrast marks are
untouched. Retained anti-aliasing on that cover goes from 10.4% of inked pixels
to 22.2%, and the glyphs thin back toward the source instead of being dilated by
the saturation.
That unlocks the trace side, which is the visible half. The blur there was never
a goal -- it exists to synthesise anti-aliasing a mask lacks, and it melts serif
terminals into blobs. With real gradients in the alpha, the cover-logo branch
drops from ~0.93px of blur to a 0.5px floor and from eps 0.5 to 0.2, at a 2400px
raster instead of 1400. Lowering eps ALONE was tried and rejected: against the
old near-binary mask it just captured the pixel staircase in finer detail.
Camping in Alaska's traced path goes 900 -> ~2500 vertices with no staircasing,
and the serif terminals keep their shape. Cost is 35ms -> 65ms of main-thread
work, once per cover-derived logo at page load, not per frame.
KeelrLeek
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