buildRegions filtered everything by visibility except the
intra-cluster edge strokes: with a search active, edges between
filtered-out nodes were still stroked into the bitmap — which had
already shrunk to the visible members — and segments crossing that
rect cut diagonal hue streaks from other clusters across the
filtered regions. Strokes now require both endpoints visible, same
law as the world rect, member discs, and label anchors. The
no-double-counting rule survives: a member touched only by a
partially-invisible edge gets its disc.
amosblomqvist
f3a3d69401