lux-rs

Pure Rust lighting and color science library for spectral, photometric, and colorimetric workflows.

Overview

lux-rs provides a native Rust API for core lighting and color science calculations without requiring Python at runtime.

The crate currently includes:

spectral foundations: wavelength grids, spacing helpers, interpolation, normalization, and single/batch spectrum models
observers and photometry: embedded standard observers, tristimulus integration, radiometric / photometric / quantal power, and mesopic support
illuminants and reference sources: blackbody, daylight family, CRI reference sources, and a registry for common CIE illuminants and LED series
color kernels: CCT, common XYZ-derived transforms, color difference, and chromatic adaptation including viewing-condition and compiled-adapter workflows
appearance models: CIECAM02, CAM16, CAM02-UCS, and CAM16-UCS forward / inverse paths plus wrapper APIs on top of the color data models
color quality metrics: CIE Ra, CIE Rf / Rg, and structured TM-30 result objects for single and batch spectral workflows

Design Goals

lux-rs is designed for:

predictable native deployment
easier integration into Rust systems
clearer data ownership and API design
parity testing against an existing scientific reference implementation

Verification

The crate is validated with Rust tests and parity checks against luxpy. Covered paths include:

spectral grid helpers
interpolation and normalization
observer and CMF access
spd_to_power, spd_to_ler, spd_to_xyz
blackbody, daylightphase, cri_ref
xyz_to_cct, cct_to_xyz
standard illuminants
one-step and two-step CAT
CIECAM02, CAM16, CAM02-UCS, and CAM16-UCS
CIE Ra
CIE Rf / Rg
TM-30 result objects

Install

cargo add lux-rs

Quick Example

use lux_rs::{spd_to_ler, spd_to_xyz, standard_illuminant, xyz_to_cct, Observer};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let observer = Observer::Cie1931_2.standard()?;
    let d65 = standard_illuminant("D65", None)?;

    let xyz = spd_to_xyz(&d65, &observer, true)?;
    let ler = spd_to_ler(&d65, &observer)?;
    let (cct, duv) = xyz_to_cct(xyz, Observer::Cie1931_2)?;

    println!("XYZ: {:?}", xyz);
    println!("LER: {:.3} lm/W", ler);
    println!("CCT: {:.1} K, Duv: {:.6}", cct, duv);
    Ok(())
}

For spectral workflows, use Spectrum and SpectralMatrix as the primary API. For tristimulus and color workflows, use Tristimulus and TristimulusSet.

Relationship To LuxPy

luxpy is a comprehensive Python toolbox for lighting and color science. lux-rs is not a binding layer around Python; it is a native Rust implementation that draws on the same problem domain and uses LuxPy for parity-oriented validation during development.

Scope difference, in short:

luxpy: broad toolbox including CAM, CAT, CRI/TM-30, photobiology, hyperspectral imaging, instrument/toolbox integrations, and more
lux-rs: focused on spectral kernels, observers, integration, reference illuminants, photometry, CCT, color transforms, CAM, and CRI/TM-30 core workflows

That means lux-rs is narrower in scope than luxpy, while still being suitable for a meaningful subset of core numerical workflows.

Citing LuxPy

If this repository or its design work benefits from luxpy, please cite the original luxpy project and tutorial paper.

Recommended citation from the upstream luxpy README:

Smet, K. A. G. (2020). Tutorial: The LuxPy Python Toolbox for Lighting and Color Science. LEUKOS, 1-23. https://doi.org/10.1080/15502724.2018.1518717

Useful upstream references:

LuxPy repository: https://github.com/ksmet1977/luxpy
LuxPy tutorial paper: https://www.tandfonline.com/doi/full/10.1080/15502724.2018.1518717
LuxPy Zenodo DOI: https://doi.org/10.5281/zenodo.1298963

License

This crate is licensed under GPL-3.0-only. See Cargo.toml and the repository license terms for details.

lux-rs 0.1.0