Challenge Overview

Procedural techniques enable the creation of large-scale, complex, and richly detailed virtual worlds without manual modeling. Coupled with global illumination (GI), these methods reveal realistic multi-bounce lighting, shadows, and color bleeding in intricate environments.

The task

Implement a global illumination shader in ShaderToy that showcases:

Vast procedural scenes

Algorithmically generated, large or infinite in scale (fractals, SDFs, noise, neural fields, tiled or hybrid systems).

Global Illumination

support multiple bounces for indirect lighting and realistic light transport.

Evaluation Criteria

• Creativity and originality of procedural representation
• Quality and accuracy of global illumination
• Visual richness and scene complexity
• Code clarity and ShaderToy efficiency
• Alignment with the theme of vast proceduralism plus GI

Winners

🥇 First place: Procedural Neon Metropolis GI
Haowen Gao, Huazhong University of Science and Technology

Procedural Neon Metropolis GI is a ShaderToy-based procedural global illumination shader showing a large hash-generated cyberpunk city.

The scene is generated entirely at runtime from procedural cells, including roads, plazas, towers, podiums, glass needle towers, metal slabs, brick/composite facades, neon signs, and warm/cool window patterns.

To make indirect lighting visible at low sample counts, the stochastic path tracing is reinforced by a deterministic procedural city irradiance field derived from the same hash cells that generate the city.

🥈 Second place: MayaSabha: Hall of Illusion
Rushikesh Vidye, University of Utah

Maya Sabha is a procedural SDF palace hall inspired by the MayaSabha from the Mahabharata, a mythical hall of illusions known for its grandeur, reflective surfaces, and deceptive spatial experience.

Scene consists of tiled palace environment with repeated chambers, arches, columns, glowing portals, water-like floors, emissive crystals, and per-cell architectural variation creating a never ending hallway.

For GI, the shader uses a progressive Monte Carlo path tracer with multi-bounce indirect lighting, next-event estimation for emissive scene lights, MIS-style weighting, glossy/specular BRDF sampling, sky lighting.

🥉 Third Place: Untitled — infinite cyberpunk city
Nan Li, University of Southern California

The shader generates an infinite cyberpunk city on a 2D XZ grid, with no pre-authored geometry. Every element is procedurally derived from cell coordinates and hash functions.

Each building facade is procedurally divided into a window grid with district-driven spacing. Windows are stochastically lit based on per-district probability. Each building selects a pair from its district's 4-color palette, and 12% of lit windows randomly override with a high-saturation neon accent for visual punch.

For GI: Unidirectional path tracing with Next Event Estimation (NEE), implemented in a single Buffer A pass with self-feedback temporal accumulation.

Entries

Rushikesh Vidye University of Utah	🥈MayaSabha: Hall of Illusion
Vinicius Hirono Goncalves Universidade Estadual de Campinas (UNICAMP), Brazil	Artificial Light
Utkarsh Sharma Indian Institute of Science (IISc)	Untitled — terrain/thunderstorm
Haowen Guo Huazhong University of Science and Technology	🥇Procedural Neon Metropolis GI
Nan Li University of Southern California	🥉Untitled — infinite cyberpunk city
Keshav Singh IIIT Delhi	Urban Scene with Multi-Bounce Path Tracing

Past winners

2025

1st Place

Lucas Domingo Alber (Karlsruhe Institute of Technology)

2nd Place

Hibiki Kirihata (Toyo University)

3rd Place

Gustaf Waldemarson (Lund University)

Honorable Mentions

Rasmus Clausen

Sparsh Nair

Eva Kato

2024

1st Place

Murilo Mesquita Carolina (Universidade Federal de Goiás)

2nd Place

Wenjian Zhou (University of Utah)

2023

Student competition cancelled

2022

Winner

Yu Chengzhong (Tokyo university of science)

Honorable Mentions

Akshay Jindal

Arthur Pereira Vala Firmino

2021

Winner

Andrew Hollis & Ajinkya Gavane (North Carolina State University)
Efficient Ray-Tracing for Urban Radiation Source Localization

Finalist

He (Anka) Chen (University of Utah)
MeshFrame: a Light Weighted Dynamic Mesh Processing Framework

2020

Winner

Evgeniya Malikova (Bournemouth University)
Ray-casting Inspired Visualization Pipeline for Multi-scale Heterogeneous Objects