cad2scad 0.2.0

Convert CAD/mesh files to parameterized OpenSCAD .scad with physics-aware Customizer sliders

cad2scad

Convert CAD/mesh files to parameterized OpenSCAD .scad with physics-aware Customizer sliders.

Unlike simple "dump polyhedron" converters, cad2scad provides a full pipeline with material-aware physics constraints.

Features

Feature	Description
Multi-format input	STL, 3MF, OBJ, PLY, OFF, GLTF/GLB, DAE, STEP*
Vertex welding	Merge duplicate vertices -> smaller .scad files
Mesh decimation	Reduce triangles while preserving shape
Multi-body splitting	Each solid -> separate OpenSCAD module
Auto-centering	Move bounding box center to origin
Color extraction	Preserve materials from 3MF/OBJ as color() wrappers
Printability analysis	Wall thickness, overhang detection, watertight checks
Physics engine	Mass, center of mass, stress, stability, warp risk
8 materials	PLA, ABS, PETG, TPU, Nylon, ASA, PC, Resin properties
Customizer output	Auto-generated sliders with physics constraints
Feature detection	Holes, flat surfaces, symmetry axes
Parameterized .scad	Scale, rotate, hollow with material-safe limits
CLI + Python API	Use from command line or as a library

*STEP support requires cadquery (pip install cadquery)

Install

pip install cad2scad

# With all optional features (decimation, splitting, pretty CLI)
pip install cad2scad[full]

Quick Start

Command Line

# Basic conversion
cad2scad model.3mf -o model.scad

# Parameterized with physics Customizer sliders
cad2scad model.3mf -o model.scad --parameterize --material PLA

# Decimate to 50% triangles, center on origin
cad2scad model.stl -o model.scad --decimate 0.5 --center

# Physics analysis
cad2scad model.3mf --analyze --physics --material PETG

# Split multi-body file into separate modules
cad2scad assembly.3mf -o assembly.scad --split

# Batch convert all STLs in a directory
cad2scad *.stl -o converted/

# Compact output (smaller file, less readable)
cad2scad model.3mf -o model.scad --compact --precision 4

Python API

# One-liner
from cad2scad import convert
convert("model.3mf", "model.scad")

# Parameterized with physics
convert("model.3mf", "model.scad", parameterize=True, material="PETG")

# Full control
from cad2scad import Converter
c = Converter(parameterize=True, material="PLA", decimate=0.5)
c.load("model.3mf")
print(c.summary())
c.save("model.scad")

# Physics engine directly
from cad2scad import PhysicsEngine
engine = PhysicsEngine("PLA")
report = engine.analyze(vertices, faces)
print(f"Mass: {report.mass_grams:.1f}g, Stability: {report.stability_score}/100")

# Feature detection
from cad2scad import Parameterizer
p = Parameterizer(material="PETG")
features = p.detect_features(vertices, faces)
print(f"Holes: {len(features.holes)}, Symmetry: {[s.axis for s in features.symmetry]}")

Output Example

Standard mode

Input: box.3mf (100x115x50mm box)

// Generated by cad2scad v0.2.0
// Source: box.3mf
module box() {
  polyhedron(points = [...], faces = [...]);
}
box();

Parameterized mode (--parameterize --material PLA)

/* [Material] */
material = "PLA"; // ["PLA", "ABS", "PETG", "TPU", "Nylon", "ASA", "PC", "Resin"]

/* [Dimensions] */
scale_x = 1.0; // [0.1:0.01:5.0] X scale (100.0mm nominal)
// ^ constraint: Min 0.8mm wall for PLA

/* [Structure] */
hollow = 0; // [0:1:1] Hollow the part
shell_thickness = 1.6; // [0.8:0.1:10.0] Shell wall thickness

/* [Physics (read-only)] */
_mass_g = 140.19;       // Estimated mass (g)
_printability = 71;     // Printability score (/100)
_stability = 85;        // Stability score (/100)
_warp_risk = 30;        // Warp risk (/100)
_safety_factor = 999.0; // Structural safety factor (x)

module box_base() { polyhedron(...); }
module box() {
  translate([offset_x, offset_y, offset_z])
  rotate([rotate_x, rotate_y, rotate_z])
  scale([_x_eff, _y_eff, _z_eff])
  if (hollow == 1) {
    difference() { box_base(); scale([...]) box_base(); }
  } else { box_base(); }
}
box();

Open in OpenSCAD -> Window > Customizer to get interactive sliders.

CLI Options

cad2scad [OPTIONS] INPUT [INPUT ...]

Optimization:
  --decimate RATIO    Reduce faces (0.0-1.0). 0.5 = halve triangles
  --decimate-target N Reduce to exactly N faces
  --center            Center mesh at origin
  --split             Split disconnected bodies into modules
  --weld TOL          Vertex weld tolerance (default: 1e-6 mm)
  --round N           Round coordinates to N decimal places

Formatting:
  --precision N       Decimal places in output (default: 6)
  --compact           Compact arrays (smaller files)
  --no-color          Strip color data
  --prefix STR        Module name prefix

Analysis:
  --analyze           Print analysis report (no conversion)
  --min-wall MM       Min wall threshold (default: 0.8mm)
  --overhang DEG      Overhang angle threshold (default: 45 deg)

Physics / Customizer:
  --parameterize      Generate OpenSCAD Customizer with physics constraints
  --material MAT      Material: PLA, ABS, PETG, TPU, Nylon, ASA, PC, Resin
  --physics           Include physics report in --analyze output

General:
  -o, --output PATH   Output file or directory
  -v, --verbose       Increase verbosity (-v info, -vv debug)
  --version           Show version

Material Database

Material	Density	Tensile	Min Wall	Max Overhang	Shrinkage
PLA	1.24	50 MPa	0.8 mm	45 deg	0.3%
ABS	1.04	40 MPa	1.0 mm	40 deg	0.7%
PETG	1.27	50 MPa	0.8 mm	40 deg	0.4%
TPU	1.21	30 MPa	1.2 mm	35 deg	0.5%
Nylon	1.14	70 MPa	1.0 mm	35 deg	1.5%
ASA	1.07	45 MPa	1.0 mm	40 deg	0.6%
PC	1.20	65 MPa	1.0 mm	35 deg	0.7%
Resin	1.12	45 MPa	0.3 mm	80 deg	0.5%

Supported Formats

Format	Extension	Notes
STL	.stl	Binary & ASCII
3MF	.3mf	Multi-body, colors
OBJ	.obj	With materials
PLY	.ply	Binary & ASCII
OFF	.off	—
GLTF/GLB	.gltf, .glb	Scenes → modules
COLLADA	.dae	—
AMF	.amf	—
STEP	.step, .stp	Requires cadquery
IGES	.iges, .igs	Requires cadquery

License

MIT