# GPS Momentum Field Tests

Current patch surface: fixed additive penalty on ordinary GPS solver edge
expansion, patched at the two ordinary relaxation callsites feeding
`0x40ba58`. Live tuning is through `momentum_weights.bin`.

## 2026-06-27 North Watson To Dogtown/Badlands

Starting context: player in North Watson near the motel/Cassius area. The two
main comparison routes fit in the same map viewport:

- The Damned / Dogtown, south into Pacifica.
- Fuel Station fast travel point in the southwest Badlands/Biotechnica flats.

Screenshots:

- `../logs/screenshots/the-damned-and-fuel-station-0.webp`
- `../logs/screenshots/the-damned-and-fuel-station-8.webp`
- `../logs/screenshots/the-damned-and-fuel-station-80.webp`

Telemetry log:

- `../logs/EdgeWeightGPS_live_momentum_ab_8_0_80.log`

Results:

| Route | Penalty | Expansion calls | Route records | Observed route |
| --- | ---: | ---: | ---: | --- |
| The Damned | 8 | 1,057,410 | 78 | Similar to vanilla; threads city blocks and a side highway. |
| The Damned | 0 | 1,110,243 | 87 | Similar visible corridor, slightly more route-record churn. |
| The Damned | 80 | 1,010,035 | 70 | Visibly smoother highway corridor, avoids City Center stair-stepping. |
| Fuel Station | 8 | 296,976 | 89 | Uses City Center roundabout/city threading. |
| Fuel Station | 0 | about 308k-314k | 90-92 | Similar visible corridor to 8. |
| Fuel Station | 80 | about 345k-347k | 77-78 | Converges onto the smoother highway corridor before splitting south. |

Interpretation:

- `0` and `8` are close visually in this location, despite small telemetry
  changes.
- `80` is a strong proof value: it changes the coarse corridor and reduces
  route-record count for the tested long routes.
- This supports the main hypothesis that a fixed per-segment additive penalty
  can optimize for smoother player-driving corridors, not merely highway class.

## 2026-06-27 Broad 80 Smoke

Telemetry log:

- `../logs/EdgeWeightGPS_momentum80_broad_smoke.log`
- `../logs/EdgeWeightGPS_momentum80_drive_validation.log`

User reported no bad routes after probing:

- Claire routes differently than nearby Sinnerman, choosing a smooth Japantown
  highway leg.
- Sinnerman still cuts through City Center, plausibly because that corridor is
  appropriate for that destination.
- Short local routing to Cassius remains fine.
- Heywood routes remain fine and may avoid some stair-stepping.
- Routes near highways but not traffic-feasible still detour appropriately.
- One NCPD bounty used a road the user had not previously seen GPS select, and
  it looked like a good fit.

Interpretation:

- No obvious local-route breakage was found at `80`.
- `80` was not immediately pathological in the sampled routes and later became
  the working default after drive validation.
- Higher values still need caution; `160` later proved too high.

Drive validation at `80`:

- The Damned / Dogtown route drove cleanly in the Outlaw at sustained high
  speed.
- The route surfaced a back/elevated highway through Japantown/Westbrook that
  the user had not seen vanilla GPS select before.
- Live minimap recalculation after a deliberate detour still worked.
- Claire route also drove cleanly. One ramp/hill surprised the driver, but the
  issue was road unfamiliarity at full speed, not bad routing.

Conclusion after the drive test: `80` is the working default.

## 2026-06-27 40/160 Bounds

Telemetry log:

- `../logs/EdgeWeightGPS_momentum40_160_tuning.log`

At `40`, the highlighted routes improved only partially:

- Claire still used the Sinnerman/City Center path instead of the smoother outer
  road.
- Sinnerman remained sensible.
- The near-highway case remained acceptable.
- The NCPD bounty took the smoother outer City Center road, but retained a
  Watson stair-step that `80` avoided.

At `160`, overcorrection appeared:

- Claire showed a questionable hairpin.
- The Damned produced a fallback/straight-line style route instead of a usable
  road route.
- The Gig/Cassius local access got worse, asking for a backtrack and hairpin
  instead of a simple nearby approach.
- NCPD bounty regressed to stair-stepping.

Conclusion: `160` is too high. The useful bracket is roughly `40 < default <
160`, with `80` currently best validated by map inspection and driving.