---
title: "Microfacet Models for Refraction through Rough Surfaces"
authors: ["Bruce Walter", "Stephen R. Marschner", "Hongsong Li", "Kenneth E. Torrance"]
year: 2007
venue: "Eurographics Symposium on Rendering (EGSR)"
arxiv: null
doi: "10.2312/EGWR/EGSR07/195-206"
source: "https://doi.org/10.2312/EGWR/EGSR07/195-206"
topics: [translucent-materials]
seed_rank: 1312
seed_batch: "sss-translucent-2026-08-25"
reviewed: "2026-08-25"
pool: "graphics"
relevance_score: 8
lineage: translucent-materials
---

# Microfacet Models for Refraction through Rough Surfaces

## One-sentence takeaway

Walter EGSR 2007 GGX BTDF: the transmission lobe every layered dielectric/skin-oil/glass stack uses.

## Problem

Predecessor chain Cook-Torrance; Stam rough BTDF. This paper's job: Walter EGSR 2007 GGX BTDF: the transmission lobe every layered dielectric/skin-oil/glass stack uses.

## Design

Walter EGSR 2007 GGX BTDF: the transmission lobe every layered dielectric/skin-oil/glass stack uses. Lineage: Cook-Torrance; Stam rough BTDF.

## Evidence

Eurographics Symposium on Rendering (EGSR) 2007. DOI `10.2312/EGWR/EGSR07/195-206`. Walter EGSR 2007 GGX BTDF: the transmission lobe every layered dielectric/skin-oil/glass stack uses.

## 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. Skin is the first character-appearance hole: translucent dermis, not another BRDF lobe. Do not claim Anoptic already has SSS.

## Bottom line

Mint this 2007 Eurographics Symposium on Rendering (EGSR) paper. Walter EGSR 2007 GGX BTDF: the transmission lobe every layered dielectric/skin-oil/glass stack uses.

## Links

- DOI: [10.2312/EGWR/EGSR07/195-206](https://doi.org/10.2312/EGWR/EGSR07/195-206)