# M00-QAR-COORD-CALIBRATION-001 — Renderer coordinate calibration

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<!-- OPENWC_INTEGRATION:ACCEPTED:M00-QAR-COORD-CALIBRATION-001:dfc1031 -->

## Ownership

- Target: M00
- Program: QAR
- Owner/Agent ID: sindo-main-codex
- Branch: `work/sindo-main-codex/m00-coordinate-calibration`
- Lease expires UTC: 2026-07-13
- Integrator: milestone integrator

## Outcome

Record the five observed build 12340 camera positions as non-proprietary golden coordinates and determine whether the existing WoW/Godot position formula round-trips them.

## Non-goals

- Introducing the M01 production `CoordinateMapper` contract.
- Changing terrain, placement, WMO, liquid, or streaming behavior.
- Claiming camera composition parity from coordinate round-trip alone.

## Paths

- Exclusive: `src/tools/verify_render_coordinate_calibration.gd`
- Shared/hotspots: `src/tools/render_baseline_manifest.json`, renderer baseline documentation
- Generated/ignored: original-client screenshots and local reports

## Contracts and data

- Public API/events: none; headless diagnostic only
- Schema/format version: additive checkpoint calibration metadata, manifest schema remains 1
- Migration/compatibility: existing capture consumers ignore additive fields
- Consumers: M00 fidelity workflow and future M01 golden fixtures

## Dependencies

- Requires: five accepted original-client build 12340 viewpoints
- Blocks: diagnosis of paired camera/placement mismatch
- External state: screenshots remain outside Git

## Verification

- Commands: coordinate calibration probe, baseline manifest, coordination and documentation gates
- Fixtures: five `reference_wow_camera` values in renderer manifest
- Fidelity evidence: positions were observed in build 12340 during the paired session
- Performance budget: negligible headless arithmetic

## Documentation deliverables

- Inline public API docs: diagnostic script header
- Module specification: renderer verification/source map update
- Data-flow diagram: baseline calibration flow update
- Sequence/state/dependency diagrams: not applicable; stateless synchronous probe
- Source map/status updates: renderer module and baseline document

## Simplicity and naming

- Important names introduced: `reference_wow_camera`, `maximum_round_trip_error`
- Simplest considered solution: direct formula probe over manifest fixtures
- Rejected complexity/abstractions: production domain mapper before M01
- Unavoidable complexity and justification: none
- Measured optimization evidence: not applicable

## Status

- State: ready
- Done: five golden camera points, headless round-trip probe, runner integration and documentation
- Next: integrator review; diagnose terrain height/placement/composition separately
- Blocked by:

## Handoff

- Commit: branch HEAD
- Results: five points passed with maximum mapping/round-trip error 0.000015
- Remaining risks: correct position arithmetic does not prove terrain height, placement or camera direction parity
- Documentation updated: `docs/RENDER_BASELINE.md`, `docs/modules/world-renderer.md`