# Route 450 distance 550 lane placement check (r297)

## Source texture and corridor samples

The default route center at distance 550 landed on the authored yellow center
marking. `roadTextureSampleAt` scored its stripe at 0.187 after bilinear
filtering. The matched route record exposes selector 3 at +2.147827 m along
the route's right vector; that candidate sampled 0.0 on the same lane texture
and remained road supported. The viewer's old 0.2 stripe threshold and 0.2
minimum improvement rejected this source candidate, leaving the player over the
yellow line.

The preview now accepts a stripe score above 0.15 and a source-texture
improvement above 0.1. The selected start is therefore shifted by the authored
2.147827 m corridor at this route point. This is a viewer lane-placement hint;
retail's final per-driver lane still depends on runtime FuturePoint values.

## Packaged Chrome drive

Chrome 150 loaded the packaged viewer at route 450, distance 550, reached “City
scene ready”, and showed the 240SX clear of the double-yellow marking in the
right-hand lane. A 3.0-second W input moved it from `(-879.1232, -422.2354)` to
`(-885.5358, -412.1708)`, a displacement of about 11.8 m. It reached 7.684 m/s
(17.2 mph) while remaining on the extracted roadway. The screenshot is
`webgl-city/review/images/432-r297-route450-distance550-lane-drive.png`.

This fixes the measured route start and verifies forward motion from it. It
does not establish lane-side selection throughout Bayview or reproduce retail
steering and AI behavior.