M2-09: Speed and distance from the track #36

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opened 2026-08-08 19:56:53 -04:00 by agent · 0 comments

agent commented

2026-08-08 19:56:53 -04:00

Member

Derive distance, duration and speed from the track and show them on the detail view.

Wes: "Gives me speed and route, and things to do with that data later." The route is M2-08; this
is the other half, and it is the thing the data was actually wanted for.

Scope

Total distance, moving time, average speed, and maximum speed.
Derived from the track at read time, not stored. The track is the record; a cached summary is a
second source of truth that can disagree with it.
Units follow the device locale.

Accuracy is the whole problem here

GPS noise inflates distance. A phone standing still produces scattered fixes that a naive
point-to-point sum reads as movement, and over forty minutes that is not a rounding error.

CLLocation carries horizontalAccuracy and speed, and M2-06 records both precisely so this
issue can use them. The plan should say which filter it applies and why — an accuracy threshold, a
minimum displacement, the device's own speed reading, or some combination — and the tests should
include a synthetic stationary track that must report approximately zero distance.

A number that is confidently wrong is worse than no number. If a filter cannot be made to
behave on real walk data, show distance and drop speed rather than shipping something that reads
as authoritative.

Done when

A real walk reports a plausible distance against a known route.
A synthetic stationary track reports approximately zero distance, not GPS drift.
A partial track says the figures cover only part of the recording.

Milestone 2 of the Stash v3 rebuild. M2 is still app-side — no sync, no account, no server. It
turns a list of memos into something you can open, listen to, read and see the route of. Sync
arrives in M3. There is no milestone/M2 label yet (creating org labels needs owner rights), so
the title carries the milestone.

Working agreement for every issue in this repo: feature branch, tested before the PR opens
(on-device where the label says so), then Wes reviews the PR and we walk the code together. Docs
update in the same commit. A PR that takes more than 20 minutes to review is too big — say so and
split it.

Derive distance, duration and speed from the track and show them on the detail view. Wes: *"Gives me speed and route, and things to do with that data later."* The route is M2-08; this is the other half, and it is the thing the data was actually wanted for. ## Scope - Total distance, moving time, average speed, and maximum speed. - Derived from the track at read time, not stored. The track is the record; a cached summary is a second source of truth that can disagree with it. - Units follow the device locale. ## Accuracy is the whole problem here GPS noise inflates distance. A phone standing still produces scattered fixes that a naive point-to-point sum reads as movement, and over forty minutes that is not a rounding error. `CLLocation` carries `horizontalAccuracy` and `speed`, and M2-06 records both precisely so this issue can use them. The plan should say which filter it applies and why — an accuracy threshold, a minimum displacement, the device's own speed reading, or some combination — and the tests should include a synthetic stationary track that must report approximately zero distance. **A number that is confidently wrong is worse than no number.** If a filter cannot be made to behave on real walk data, show distance and drop speed rather than shipping something that reads as authoritative. ## Done when - [ ] A real walk reports a plausible distance against a known route. - [ ] A synthetic stationary track reports approximately zero distance, not GPS drift. - [ ] A partial track says the figures cover only part of the recording. --- *Milestone 2 of the Stash v3 rebuild. M2 is still app-side — **no sync, no account, no server**. It turns a list of memos into something you can open, listen to, read and see the route of. Sync arrives in M3. There is no `milestone/M2` label yet (creating org labels needs owner rights), so the title carries the milestone.* *Working agreement for every issue in this repo: feature branch, tested before the PR opens (on-device where the label says so), then Wes reviews the PR and we walk the code together. Docs update in the same commit. A PR that takes more than 20 minutes to review is too big — say so and split it.*

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2026-08-08 19:56:53 -04:00

agent referenced this issue from a commit

2026-08-10 01:08:17 -04:00

M2-09: speed and distance from the track [pre-human-testing]

agent referenced this issue from a pull request that will close it,

2026-08-10 12:08:49 -04:00