# AcademySoftwareFoundation/OpenShadingLanguage

Advanced shading language for production GI renderers

Repository: https://github.com/AcademySoftwareFoundation/OpenShadingLanguage
Canonical: https://ross.abutalabs.com/products/openshadinglanguage
Language: C++
License: BSD-3-Clause
License Family: permissive
Topics: osl, shading-language, shaders, c-plus-plus, computer-graphics, computer-language, llvm, vfx, open-shading-language
Last push: 2026-08-25T22:32:40+00:00

## Health v2 (maintenance only)
Score: 94/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 84, longevity 100
- inputs: {"age_days": 5655, "days_push": 8, "days_rel": 31, "gap_med": 31.0, "n_releases_24m": 17}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2325, forks 414 (observed 2026-08-28T04:06:37.410241+00:00)

## What it is
Open Shading Language (OSL) is a small, C-like programmable shading language with a compiler and runtime library for advanced production renderers, designed for describing materials, lights, displacement, and pattern generation. Originally developed by Sony Pictures Imageworks, it is the de facto standard shading language for VFX and animated feature films and received an Academy Award for Technical Achievement in 2017.

## Use cases
- write custom material shaders for a path tracer
- programmable shading in a GI renderer
- define BSDFs and radiance closures for film rendering
- pattern generation and displacement shaders for VFX
- integrate a production shading language into a renderer
- author lights and materials for animated feature films

## When to choose
- building a physically based renderer that needs programmable materials
- working in VFX or animation where OSL is the industry-standard shading language
- you need first-class radiance closures, BSDFs, and deferred ray tracing
- you want a production-proven, permissively licensed (BSD-3-Clause) shading system

## When to avoid
- real-time game engines, where GLSL/HLSL/SPIR-V ecosystems are standard
- simple rendering projects that don't need a full programmable shading language
- non-graphics applications needing a general-purpose scripting language

## Facets
- artifact type: library
- maturity: stable
- function: programming-language, compiler, graphics, simulation
- domain: graphics, programming-languages
- platform: cpp, cross-platform
- tags: shading-language, rendering, vfx, material-shaders, llvm-jit, academy-award, computer-graphics, llvm

## Member repositories
- AcademySoftwareFoundation/OpenShadingLanguage (main) score 94

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:37.410241+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:38:22.771194+00:00, confidence not recorded.
  - readme: https://github.com/AcademySoftwareFoundation/OpenShadingLanguage (fetched 2026-08-28T04:06:37.410241+00:00, sha a6acdd9e83ba)
- Data as of 2026-08-30T08:39:29.467469+00:00.