reference-to-3d-reconstruction

name	reference-to-3d-reconstruction
description	Reconstruct a measured Blender asset from one or more image references, wireframes, logos, or orthographic views, then validate scale, registered cameras, landmarks, silhouette, materials, and OVRTX output. Use for reference-locked modeling, orthographic image registration, pixel-to-world calibration, or explicit inferred-depth reporting; it needs Blender/MCP and the installed add-on.

Reference to 3D reconstruction

Treat supplied images and measurements as the source of truth. The goal is a repeatable asset with documented assumptions, not a plausible but unmeasured mesh.

Plan and register references

1. Preserve originals and record file hashes, pixel dimensions, orientation, crop, lens/orthographic assumptions, and known dimensions. Do not silently stretch a reference to fit a camera.
2. Classify the task: single-view concept, front/side/top orthographic fit, multi-view reconstruction, wireframe-to-mesh, logo/mascot, or texture-driven surface. For single views, label depth as inferred.
3. Establish Blender units and a named REF_* collection. Add image empties or planes with locked transforms; keep them out of final renders/exports.
4. Create measurable landmarks (corners, centerlines, extrema, joints, and silhouette breaks). Store expected image-space positions and tolerances.

Before modeling, read references/reference-registration.md. Follow its idempotent image-empty recipe, camera conventions, calibration and landmark schemas. Run scripts/reference_projection_report.py in Blender after registration and after any camera, scale, or silhouette change. Do not accept a visual overlay without the resulting projection report.

Reconstruction loop

1. Block out with primitives at the measured scale. Lock the reference camera and solve projection before adding detail.
2. Fit the primary silhouette and major parts across all available views. Use separate objects for independently moving parts and preserve stable names. Avoid adding hidden geometry to cover a projection mismatch.
3. Refine only after silhouette/landmark error is within the declared tolerance. Apply controlled bevels, subdivision, and topology repair while checking proportions at thumbnail size and in greyscale.
4. Assign materials/UVs through texture-uv-material-workflow; validate the reference look separately from geometric fit.
5. Render a neutral Blender control and the same camera through ovrtx-current-scene-workflow. Compare framing, silhouette, normals, occlusion, and color with label-free images plus a numeric fit report.

Use blender-community-skill-bootstrap to install upstream blender-modeling and blender-cameras recipes when those optional skills are absent. Use blender-python-execution for the MCP transaction. Keep reference images in a named COL-reference collection and create them through Blender's data API; do not depend on the current selection.

Use blender-camera-framing only for beauty or diagnostic subject containment. Do not use it to solve a registered reference camera: registration fixes the camera from calibration and measures object error against that camera.

Acceptance gates

• Reference files and source .blend remain immutable; derived outputs use a caller-selected cache/output folder.
• Every fit claim names camera/projection, landmarks or mask metric, tolerance, and view(s) tested. “Looks close” is not a fit result.
• Image planes, guides, and diagnostic overlays are excluded from beauty renders and USD unless explicitly requested.
• Mark unseen depth, occluded surfaces, and inferred materials as assumptions.
• Require every view to state whether depth is measured, constrained by another view, or inferred. A passing 2D projection report does not validate depth.
• A failed OVRTX render is a runtime/add-on diagnostic; use the documented status and log surfaces to diagnose it.

Handoff

Return the requested .blend or export plus the camera/scale assumptions, fit metrics, and unresolved ambiguities needed to judge the reconstruction. Add a reference manifest, source map, or previews only when the handoff benefits from them. For USD/SimReady, continue with the dedicated skill.