# 3D Form Model Report & Export

> Measure a form model by tag and export its geometry as OBJ or STL. Inspect a Kerfwise Form Studio project for object bounds, gross surface area, volume and triangle counts. Group quantities by tag and download the normalized project, OBJ and STL files.

Part of usefulweb.site (https://usefulweb.site/). Results are deterministic calculations from the inputs and the listed assumptions; the API returns exactly what the web page shows.

## Use it
- Human interface: https://kerfwisemodelreport.usefulweb.site/ (interactive tool at https://kerfwisemodelreport.usefulweb.site/tool)
- JSON API: POST https://kerfwisemodelreport.usefulweb.site/api/v1/calculate with a JSON object of inputs (schema: https://kerfwisemodelreport.usefulweb.site/api/v1/tool)
- OpenAPI: https://kerfwisemodelreport.usefulweb.site/openapi.json
- MCP (Streamable HTTP): https://kerfwisemodelreport.usefulweb.site/mcp - tool `kerfwise_model_report`

## Inputs
- project (textarea): Form Studio project JSON
- visibleOnly (boolean): Report and export visible solids only

## Method
- All geometry is in millimetres, with Z up. Accept one simple, non-self-intersecting footprint without holes, 3–64 vertices and at least 1 mm² area. Extrude vertically, then rotate around Z and translate.
- Triangulate both caps and each side with consistent outward winding. Each separate prism is closed; intersecting prisms are not unioned. Surface = 2 × footprint area + perimeter × height; gross volume = footprint area × height.
- Models contain at most 128 solids and eight saved camera views. Coordinates, heights and profiles are bounded. OBJ and ASCII STL use millimetres; STL does not embed a unit. These are concept models, separate from cabinet cut lists or machining instructions.
- Visible-only export is on by default. Hidden solids can be included explicitly. Report bounds are axis-aligned after rotation; quantities sum complete solids, so touching internal faces and overlapping volumes remain counted.

## Limits
- Gross quantities count complete solids, including overlaps and internal faces. STL is unitless; import it as millimetres.