github-featured/earthtojake--text-to-cad

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knewnothing-git cb6f984bbc fix(dfam-check): address maintainer review on #265

Blockers
--------
1. requirements.txt was missing scipy, networkx and lxml. With only
   trimesh/numpy/rtree installed the first measure of any mesh died with a raw
   ModuleNotFoundError from mesh.body_count, and .3mf could not load at all.
   Reproduced in a clean venv, then confirmed fixed there: all four advertised
   formats now load and measure. Only scipy is mirrored into
   requirements-dev.txt; networkx and lxml are already listed under the repo
   tests block, matching how trimesh is handled.

2. Wall thickness is now measured per connected body. Cast against a whole
   assembly, a ray can leave one body, cross a mating clearance and land on
   its neighbour, recording the fit gap as a wall - so a tight-clearance
   assembly reported a wall violation no single part had. _wall_facts splits
   first and measures each body against itself, pooling the results and adding
   a per_body breakdown. Sample budget is shared by surface area with a floor
   so small bodies are still sampled.

Should-fix
----------
3. Each fact family now runs through _safe and degrades to an error field.
   A planar mesh dies in convex_hull; previously that cost the user the whole
   report, including the facts that had computed.

4. New scale block reports bbox_diagonal_mm and units_suspect. A meters-scale
   mesh sits under the 0.1 mm on-plate tolerance, so every down-facing face
   reads as on-plate and the part looks like a flawless print. SKILL.md now
   branches on the measured field instead of asking the agent to eyeball the
   bounding box.

5. Added the skill to the README table and the docs page array.

6. process-limits.md now names which rows have a measured counterpart today
   (walls, self-supporting angle) and which do not (hole diameter, positive
   feature, unsupported bridge), closing the eyeballing loophole.

SKILL.md also gained a rule to attribute an assembly's wall violation to the
body it belongs to.

Verification
------------
- Clean venv built from the skill's own requirements: 26 checks covering
  multi-body clearance, 81k-face performance, a 42-body assembly, planar,
  meters-scale, broken export, all four formats, degenerate mesh.
- Per-body change costs ~150 ms on an 81k-face mesh (7493 -> 7643 ms); the
  bulk of that time is trimesh's pure-Python ray fallback, not the split.
- Real part measurements unchanged: L-bracket still 1200 mm2 unsupported,
  9.0 mm median wall.
- gcode/urdf/dxf suites fail identically with and without this change; those
  are pre-existing.

2026-08-20 22:37:39 +05:30

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name, description

name	description
dfam-check	Measure mesh files against Design for Additive Manufacturing (DfAM) rules and report printability findings per process (FDM, SLS, SLA/DLP, metal PBF, MJF). Use when the user asks whether a part is printable, wants overhang/wall-thickness/support analysis of an `.stl`, `.obj`, `.ply`, or `.3mf` mesh, wants a build-orientation recommendation, or wants DfAM redesign guidance before slicing with `$gcode` or regenerating geometry with `$cad`.

name

description

dfam-check

Measure mesh files against Design for Additive Manufacturing (DfAM) rules and report printability findings per process (FDM, SLS, SLA/DLP, metal PBF, MJF). Use when the user asks whether a part is printable, wants overhang/wall-thickness/support analysis of an `.stl`, `.obj`, `.ply`, or `.3mf` mesh, wants a build-orientation recommendation, or wants DfAM redesign guidance before slicing with `$gcode` or regenerating geometry with `$cad`.

DfAM Check

Provenance: maintained in earthtojake/text-to-cad. Use the installed local skill files as the runtime source of truth; the repository link is only for provenance and release review.

Use this skill to produce conservative, evidence-backed DfAM reports for mesh files before slicing or printing. It measures geometry facts locally and compares them against per-process design limits; it never slices, uploads, or starts print jobs.

Geometry Inspection

Use scripts/dfam_tool.py in the active project Python environment for all geometry facts (requires trimesh, numpy, rtree). The tool is fact-only: it reports measurements and never emits pass/fail or readiness statuses. Comparisons and verdicts belong to this workflow. Do not estimate wall thickness, overhang angles, or support volume by eye or from renders when the tool can measure them.

python scripts/dfam_tool.py measure part.stl --angle-limit 45
python scripts/dfam_tool.py orientations part.stl --angle-limit 45

Set --angle-limit to the target process's self-supporting angle from references/process-limits.md before measuring, and re-run when the target process changes: the aggregate support-area facts are binned against it.

STEP/STP input is boundary-representation CAD, not a mesh. When the $cad skill is installed, export an STL sidecar with it first, then measure the STL here. Report that remediation instead of attempting raw STEP parsing.

Workflow

Collect print intent: target process, material, layer height, and any machine or material datasheet the user can provide. If the process is unknown, measure once with the default 45° limit, then present findings per candidate process rather than guessing a single verdict.
Read references/process-limits.md and select the limit column for the target process. A user-provided machine/material datasheet overrides the defaults; cite whichever source is used for every comparison.
Run measure on the exact upload file. Do not inspect only a generator script, source CAD model, or console summary of the file.
Run orientations when the process requires supports and the measured support area is nonzero. Report any candidate that materially reduces support area, with its build-height tradeoff.
Compare each measured fact to the cited limit and report findings with restrained status labels:
- ✅ pass: the measured fact satisfies the cited limit.
- ❌ fail: a measured fact directly violates the cited limit.
- ❓ need more info: missing process context, unmeasured geometry, sampling too sparse to trust, or tool limitations.
Order findings by severity: watertightness first (blocks slicing for every process), then wall thickness, then overhangs/supports, then orientation and cost signals.

Comparison

Compare only trustworthy pairs of evidence.

Cite the limit source (process-limits table row, or the user's datasheet field) and the measured fact (JSON field path) for every finding.
Treat p05_mm below the wall-thickness limit as a violation even when min_mm alone could be a sampling outlier; report both values.
On an assembly, wall_thickness reports body_count and a per_body breakdown. Attribute a violation to the body it belongs to; a thin figure pooled across bodies is not a finding against the part as a whole.
Do not apply support-angle findings to powder processes (SLS, MJF); the relevant powder-process check is trapped-volume powder escape, which this tool does not yet measure — report that as ❓ need more info when enclosed cavities are likely.
Do not silently rescale geometry. scale.units_suspect is measured from the bounding-box diagonal: when it is true, the source is probably in meters or inches, every down-facing face reads as resting on the plate, and overhang and support figures of 0.0 mean nothing. Report a unit/scale finding and ask the user to confirm units before comparing anything against a material limit.
Support-volume ratios are coarse upper bounds; report them as cost signals, not hard failures, unless the user has set an explicit budget.

Redesign Handoff

For every ❌ fail, include a concrete, plain-language redesign instruction with target numbers (for example "thicken the wall at [12.4, 3.0, 8.1] from 0.6 mm to ≥1.2 mm" or "chamfer the overhang at [23.3, 10.0, 52.0] to ≥45°"). When the $cad skill is installed, offer to apply the redesign instructions with it and re-measure the regenerated geometry here, repeating until no ❌ fail findings remain. When $cad-viewer is installed, hand the measured file path(s) to it so the user can inspect the findings visually.

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