MoonModel creates hollow, terrain-accurate lunar globes as generic, material-aware 3MF files. It supports a one-piece display Moon, an eight-section large Moon, arbitrary named filament colors, nozzle-aware tonal dithering, optional coordinate lines, magnetic-box configuration, and a separate orbital-triskelion stand.

Setup and use

bundle install
bundle exec ruby bin/moon_model

The executable begins with require "bundler/setup", so all application imports use the locked Bundler environment. To reproduce a run:

bundle exec ruby bin/moon_model --config config/example.yml --output build/example

The wizard first asks for a model name, then asks about the printer/tooling envelope, intended use, palette, grid, size or scale, vertical exaggeration, and assembly hardware. Named models are written to build/<name>/. Selecting an existing generated name offers to revise it, using its saved configuration as the defaults for a fresh wizard run. It displays maximum one-piece/eight-section sizes in millimeters and inches and a terrain-relief cheat sheet before generation.

Output

One-piece runs create moon.3mf. Segmented runs create eight print files, an assembled preview, and an assembly-key file. The optional one-piece, support-free orbital stand is emitted as orbital_triskelion_stand.3mf without a material assignment; its footprint scales with the Moon and is capped to the usable printer bed. Its saddles use conservative terrain-radius bounds so the Moon can be rotated freely while retaining a configurable 10 mm default clearance above the central hub. Every run includes its reusable YAML configuration, a slicer/spool manifest, and assembly instructions. Revisions are generated in a temporary directory and atomically replace the prior generated directory only after successful validation; unrelated directories are never overwritten. --output DIR continues to override the named default location.

Colors are closed surface inlay volumes over a continuous structural shell. Palette entry order defines filament slots 1 through N. The 3MF records portable material names/display colors and Bambu Studio part names/slot assignments; confirm the numbered slots against physical AMS or external-spool filaments. The structural shell and first-color surface remain separate bodies assigned to the same filament 1, so an N-color Moon may show N+1 bodies. The file has no fixed palette limit, though the printer and filament system will impose practical limits.

Modeling notes

The first palette entry is the structural material.
Reflectance is mapped across the palette by perceptual luminance and deterministic spatial dithering.
Grid lines override reflectance. They are contrasting inlays for multicolor output and debossed for one-color output.
A requested final-envelope diameter is rescaled after exaggeration so it fits. Datum/scale mode preserves the lunar datum diameter and reports the larger resulting envelope.
One-piece spherical prints require slicer-generated adhesion/support. Section files are moved above the build plane but may still need slicer-specific support decisions.

See data/SOURCES.md for data provenance and ROADMAP.md for milestones and acceptance gates.

Developer visual QA renders front, back, left, right, top, bottom, and isometric views:

blender --background --python script/render_previews.py -- build/example/moon.3mf build/example/previews