Module stl 

STL format import and export (binary and ASCII).

This module provides conversion between STL files and 3MF Model structures. Both binary and ASCII STL formats are supported.

STL Formats

Binary STL

The binary STL format consists of:

• 80-byte header (typically unused, set to zeros)
• 4-byte little-endian unsigned integer triangle count
• For each triangle:
  • 12 bytes: normal vector (3 × f32, often ignored by importers)
  • 12 bytes: vertex 1 (x, y, z as f32)
  • 12 bytes: vertex 2 (x, y, z as f32)
  • 12 bytes: vertex 3 (x, y, z as f32)
  • 2 bytes: attribute byte count (typically 0)

ASCII STL

The ASCII STL format is a text-based format with keyword-delimited geometry:

• Keywords are case-insensitive (real-world files use both uppercase and lowercase)
• Multiple solids per file are supported (each becomes a separate object)
• Solid names with spaces are supported

Auto-Detection

StlImporter::read() automatically detects the format using the file size formula. Use StlImporter::read_binary() or StlImporter::read_ascii() for explicit format selection.

Examples

Importing STL (auto-detect)

use lib3mf_converters::stl::StlImporter;
use std::fs::File;

let file = File::open("model.stl")?;
let model = StlImporter::read(file)?;
println!("Imported {} objects", model.build.items.len());

Exporting Binary STL

use lib3mf_converters::stl::BinaryStlExporter;
use lib3mf_core::model::Model;
use std::fs::File;

let file = File::create("output.stl")?;
BinaryStlExporter::write(&model, file)?;

Exporting ASCII STL

use lib3mf_converters::stl::AsciiStlExporter;
use lib3mf_core::model::Model;
use std::fs::File;

let file = File::create("output.stl")?;
AsciiStlExporter::write(&model, file)?;

Structs

AsciiStlExporter

Exports 3MF Model structures to ASCII STL files.

BinaryStlExporter

Exports 3MF Model structures to binary STL files.

StlImporter

Imports STL files (binary or ASCII) into 3MF Model structures.

Enums

StlFormat

Detected STL file format.

Functions

detect_stl_format

Detects whether an STL file is binary or ASCII.