Both found reviewing the gesture on device.
The gutter is 24 stacked hour-tall boxes, each rounding its own height to
whole pixels, while the hour lines and event blocks are drawn at the
fractional height. A pinch lands on fractional heights constantly, so the
two sat on different grids — at 56.4px per hour the 23:00 label is ~9px
off the line it names — and the whole label column jumped as the pinch
drifted across each half pixel. A pinch now lands on whole pixels, so
every part of the timeline shares one grid.
Zooming out stopped at a fixed 24dp per hour, which is below the height
that fills the screen on a phone, so you could shrink the day until it
left dead space under midnight. The floor is now the height at which all
24 hours exactly fill the viewport: past that there is no more day to
uncover. It is applied when the height is resolved rather than only in
the gesture, so a height pinched in landscape still fills portrait.
Jean-Luc Makiola
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