virtual-textures

A minimal prototype implementing virtual texturing without hardware sparse textures, put together while writing How Virtual Textures Really Work.

This repository contains a small prototype that implements the core ideas behind virtual texturing. It focuses on correctness and clarity rather than completeness or performance. The project demonstrates how large textures can be split into pages, mapped through a GPU page table, and streamed into a physical atlas on demand based on what the GPU actually samples.

Virtual texturing is usually explained at a high level and implemented behind layers of engine code. This prototype strips it down to the essentials so the system can be understood and reasoned about end to end.

• Virtual texture sampling via page table indirection
• Physical texture atlas with page residency
• GPU feedback pass to detect page usage and mip selection
• CPU-side page cache and simple eviction
• Page padding for bilinear filtering

The demo renders a simple terrain using a virtual texture. A minimap overlay displays currently resident pages and feedback results, making page streaming behavior visible in real time. Camera movement and zooming trigger higher-resolution tiles to be requested and loaded incrementally.

• Rendering: Powered by VGLX which handles internal dependencies.
• Tile Generation: Textures are generated offline using vtile.
• Assets: The UV grid texture is by Maurus Löffel. You can download the source image here.

The project uses CMake and VGLX for rendering. The easiest way to install VGLX is with the Python installer included in the repository. It guides the process and builds the engine using the correct presets for your system.

# clone the repository
git clone https://github.com/shlomnissan/vglx.git
cd vglx

# run the installer
python3 -m tools.installer.main

With VGLX installed, you can build this prototype like any other CMake project.

# clone the repository
git clone https://github.com/shlomnissan/virtual-textures.git
cd virtual-textures

# configure cmake
cmake -S . -B build

# build the project
cmake --build build

Copyright (c) 2025-present Shlomi Nissan
https://shlom.dev | https://vglx.org

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a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
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permit persons to whom the Software is furnished to do so, subject to
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The above copyright notice and this permission notice shall be
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