---
title: "Calculating the acoustical room response by the use of a ray tracing technique"
authors: ["Asbjørn Krokstad", "S. Strøm", "S. Sørsdal"]
year: 1968
venue: "Journal of Sound and Vibration"
arxiv: null
doi: "10.1016/0022-460X(68)90198-3"
source: "https://doi.org/10.1016/0022-460X(68)90198-3"
topics: [ray-tracing, geometric]
seed_rank: 1685
seed_batch: "audio-harvest-2026-09-09"
reviewed: "2026-09-09"
pool: "graphics"
relevance_score: 10
lineage: geometric-acoustics
---

# Calculating the acoustical room response by the use of a ray tracing technique

## One-sentence takeaway

Krokstad/Strøm/Sørsdal 1968: first practical computerized ray-tracing of rooms — geometric acoustics becomes a program.

## Why it matters here

Every game audio ray is a grandchild of this JSV paper. Historical root of Vorländer hybrids and GSound. Mint as the geometric-acoustics origin, not as a realtime algorithm.

## Key ideas

- **Rays as energy particles.** Trace from source, tally arrivals at receiver volumes.
- **Room acoustics, not optics.** Absorption on hits; build decay curves.
- **Journal of Sound and Vibration 1968.** Seminal computerized GA.
- **No diffraction, no phase.** Energy, not pressure — the geometric split from wave methods.

## Caveats

1968 computers; no interactive rates, no HRTF. Historical. Image sources (1674) are the specular cousin, not a remint.

## Links

- DOI: https://doi.org/10.1016/0022-460X(68)90198-3