Frame-by-frame, the marks were not fading in late — they were invisible
for the first half of their journey and then appearing already near the
destination, row by row from the top down.
A mark's two homes are in different rows: the dot for the 20th sits a third
of the way down the compact grid, its bar most of the way down the expanded
one. The events box clips to its own row, so a mark arriving there is out
of bounds — and undrawn — until it crosses in. The lower the row, the
further it travels and the later it showed, which is exactly the order the
capture shows them appearing in.
Rendering in place rather than in an overlay is what subjects marks to that
clip, and that is worth keeping — it is what puts the whole grid in one
z-order. So the clip yields instead, and only while pieces are in flight;
at rest it still stops a bar spilling into the row below.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Jean-Luc Makiola
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