[Myuavbug66]

Experimental contribution for maintainer review

This is an unofficial experimental fork, not reviewed, approved or endorsed
by CNC Kitchen. Testing is limited to one Windows development computer, not
independent validation or broad platform testing. Opening this draft does not
imply approval. I welcome guidance on splitting this into smaller contributions.

Proposed changes

• Mesh Tools Bridge gap: surface-constrained picks/drawn crossings, adjustable
  guide counts, bowed geometry, explicit validated preview/Apply, guide/bend
  correction choices, undo and editable project persistence. Original scan
  vertices remain unchanged; geometry checks are not bypassed.
• Visible-only triangle selection/deletion: current-view selection, Add/Remove,
  whole-mesh inversion, underside selection, clipping and dense/subpixel
  visibility. Exact oriented-face mapping preserves unselected geometry despite
  BVH face reordering. Removal requires preview and two separate confirmations.
  Through selection remains available as legacy behavior.
• Project saves: numbered revisions, retained browser-directory handles, and
  native Windows localhost Save As, including cancellation/error handling.
• Exports: independent remembered export folder shared across formats without
  changing the project-save folder; opt-in open-sheet STEP export; immediate
  feedback and duplicate-click protection. All-sheet exports skip solid-only
  mending readback, not explicit geometry verification.

The implementation stays within the plugin architecture. There are no new npm
dependencies. New native save endpoints require same-origin loopback requests
and single-use expiring selections. Ordinary hosted export behavior is retained.
New bridge edit entries require a compatible customized build.

Scope deliberately excluded

Windows installer packaging, fork-only UI branding, local sign-in startup,
SpaceMouse focus changes, private scans, tokens, local settings, personal
instructions and development records are not included in this contribution.
The experimental installer is distributed separately to invited reviewers;
no public EXE release is being requested here.

Validation

• Production build and TypeScript check passed.
• Plugin-boundary checker passed in the isolated contribution checkout.
• 220 focused geometry, command, persistence and output tests passed.
• Two native Save As tests passed separately on three monitors. One positioning
  assertion failed when run alongside CPU-heavy/browser tests, then passed
  when run alone; the native test is timing/focus-sensitive under contention.
• Isolated Edge browser regressions passed for bridge preview/Apply/Undo,
  correction and persistence, visible selection/deletion (including 1,960,000
  overlapping triangles), retained output folders/all export formats and
  open-sheet STEP feedback/readback.
• git diff --check passed.

The full test suite and other OS/clean-machine combinations have not been run
for this submission. Exporting a sheet does not establish that arbitrary
reconstructed geometry is valid or ready for downstream CAD.

Contribution process

This work was developed with GitHub Copilot assistance (credited in the commit).
I understand that the maintainer may request changes or decline it, and that
accepted contributions are applied in the development repository and credited
in a later publish as described in CONTRIBUTING.md.

CLA: pending my personal review/signature. No agreement comment has been
posted on my behalf.

[github-actions]

All contributors have signed the CLA. Thank you.
_{Posted by the CLA Assistant Lite bot.}

[Myuavbug66]

I agree to CLA.md

[Myuavbug66]

I made these changes simply because I needed as I was working on the first Test project toll your scan ruler app. I found for these functions and copilot in VS code If it could help me add these functions it said it could so I did. So now I'm trying to make it available for you if you want. This is one of the best App I have seen in a long time. And if you like what I'm doing I lots of things to contribute.
Again thanks for developing this app It is greatly needed. I am retired and completely nonprofit but do a lot of scanning and engineering designing 3D printing for personal use only. I've been trying to duplicate or work around what you have created for a very long time and will be glad to help improve it anywhere I can