RFC 1 · Should a sheet animate from screen geometry or reading direction?

[jihoons0]

Labels: RFC motion

In a horizontal interface a bottom sheet slides up: the direction matches gravity and the nearest screen edge, and dismissal downward feels natural. In a vertical, right-to-left interface those two forces split apart — dismissing toward the bottom-right runs with gravity but against the reading direction. Which axis should win?

Where it shows up here: sheet, dialog, toast. Today the demos favor the reading axis, but this is not settled.

Open questions:

• Does the answer differ for a transient toast vs. a modal sheet the user dismisses deliberately?
• Should the enter and exit directions ever differ (enter with reading flow, exit with gravity)?
• What does the gesture feel like on a touchscreen when the swipe-to-dismiss vector fights the scroll axis?

Write-up: https://vertically.works/challenges#motion-direction
Propose your answer as a PR. Strong answers get merged into the spec.