# M14-04B Status

status: done  
task: Chromium DPR 1/1.5/2/3 canvas and raycast consistency  
updated: 2026-08-19 America/New_York  
enablingTask: false  
parityStateChange: false

## Scope

Shared viewport DPR and CSS-bounds NDC helpers now drive the main-thread and Offscreen viewport
boundaries. Chromium production verification ran at device scale factors 1, 1.5, 2 and 3; the
declared renderer cap of 2 was applied, backing dimensions matched the browser canvas, CSS dimensions
remained `679x321`, and the same center raycast selected the same object at every scale.

## Evidence

- `npm --prefix web run build` passed.
- `npm --prefix web run test:chromium-dpr-consistency` passed: 2 protocol tests and 4 real Chromium
  production contexts.
- Checker output: `chromium-dpr-ok dpr=1,1.5,2,3 css=679x321 selection=stable execution=DISABLED next=M14-04C`.
- `npm --prefix web run typecheck` and `git diff --check` passed.

## Next Task

`M14-04C`: Chromium mouse/touch/pen pointer identity and cancellation contract.