---
title: "A Radiative Transfer Framework for Non-Exponential Media"
authors: ["Benedikt Bitterli", "Srinath Ravichandran", "Thomas Müller", "Magnus Wrenninge", "Jan Novák", "Steve Marschner", "Wojciech Jarosz"]
year: 2018
venue: "SIGGRAPH Asia / TOG"
arxiv: null
doi: "10.1145/3272127.3275103"
source: "https://doi.org/10.1145/3272127.3275103"
topics: [subsurface-scattering]
seed_rank: 1336
seed_batch: "sss-translucent-2026-08-25"
reviewed: "2026-08-25"
pool: "graphics"
relevance_score: 7
lineage: subsurface-scattering
cites:
  - title: "The Rendering Equation"
    url: "https://doi.org/10.1145/15922.15902"
    year: 1986
    arxiv: null
    doi: "10.1145/15922.15902"
  - title: "Path Traced Subsurface Scattering using Anisotropic Phase Functions and Non-Exponential Free Flights"
    url: "https://graphics.pixar.com/library/PathTracedSubsurface/paper.pdf"
    year: 2017
    arxiv: null
    doi: null
see:
  - "152-the-rendering-equation"
  - "1309-path-traced-subsurface-scattering-using-anisotropic-phase-functions"
---

# A Radiative Transfer Framework for Non-Exponential Media

## One-sentence takeaway

Non-exponential RTE; production already wanted this (Wrenninge).

## Problem

Predecessor chain Exponential free-flight → non-exp. This paper's job: Non-exponential RTE; production already wanted this (Wrenninge).

## Design

Non-exponential RTE; production already wanted this (Wrenninge). Lineage: Exponential free-flight → non-exp.

## Evidence

SIGGRAPH Asia / TOG 2018. DOI `10.1145/3272127.3275103`. Non-exponential RTE; production already wanted this (Wrenninge).

## Limitations

Read the cited predecessors before treating this as a drop-in Anoptic shader. Do not claim the library already implements it.

## Implications for Broadside

Anoptic has a forward+ mesh renderer and is betting on FMM+RC 3D GI. Translucent materials / SSS is the missing appearance model for skin, marble, wax, leaves, and interiors. Do not claim they already have SSS.

## Bottom line

Mint this 2018 SIGGRAPH Asia / TOG paper. Non-exponential RTE; production already wanted this (Wrenninge).

## Links

- DOI: [10.1145/3272127.3275103](https://doi.org/10.1145/3272127.3275103)