GGPO
GGPO is an open-source networking library for peer-to-peer games that uses rollback to keep play moving while remote inputs travel between players.
What GGPO is
GGPO is an open-source networking library for peer-to-peer games that uses rollback to keep play moving while remote inputs travel between players. It predicts inputs and runs gameplay speculatively; when actual inputs differ, the game can resimulate from the divergence point. The approach targets fast-paced games requiring precise inputs and frame-perfect execution. Integration requires the game to save and load state and execute a frame without rendering its result, alongside a fully deterministic peer-to-peer engine. The repository includes SDK code, documentation, and sample applications. Its Vector War sample demonstrates synchronizing two clients and includes two-, three-, and four-player examples. The MIT License permits commercial and non-commercial use, with attribution appreciated but not required. The project is free at no cost. Building is currently available only on Windows and requires Visual Studio 2019 and CMake.
Good
- Rollback prediction keeps gameplay moving
- Supports two-, three-, and four-player samples
- MIT license allows commercial use
- Includes SDK, documentation, and samples
- Free at no cost
Watch out
- Builds currently available only on Windows
- Requires Visual Studio 2019 and CMake
- Needs a fully deterministic game engine
- Integration requires state save and load
Who it suits
GGPO suits developers building deterministic peer-to-peer games where precise, frame-level input matters. It is intended for teams able to implement state saving, loading, and resimulation.
Verdict
GGPO provides rollback networking components and examples for deterministic peer-to-peer games. Developers must meet its integration requirements and use the currently Windows-only build setup.
Plans and prices
From GGPO's own pricing page, checked 9 Oct 2001.
| Plan | Price | What it gives you |
|---|---|---|
| GGPO SDK (MIT License) | Free | Free for commercial and non-commercial use · Attribution appreciated but not required |
The facts
Each one read from GGPO's own pages, with the date it was checked.
Where it runs
- Build platform
- The project README says building is currently available only on Windows, with efforts underway to port it to other platforms.checked 9 Oct 2001
What it does
- Build tools
- Windows builds require Visual Studio 2019 and CMake.checked 9 Oct 2001
- Contact
- The official site offers a contact form for licensing inquiries on terms other than the MIT license and other messages.checked 9 Oct 2001
- Engine requirement
- Rollback networking is designed to integrate with a fully deterministic peer-to-peer engine.checked 9 Oct 2001
- History
- The official site says GGPO was created in 2009 and pioneered rollback networking in peer-to-peer games.checked 9 Oct 2001
- Integration
- Integration requires the game to save and load state and execute a frame of game state without rendering its outcome.checked 9 Oct 2001
- Intended games
- The SDK is designed to hide network latency in fast-paced games that require precise inputs and frame-perfect execution.checked 9 Oct 2001
- License
- GGPO is available under the MIT License for commercial and non-commercial use; attribution is appreciated but not required.checked 9 Oct 2001
- Purpose
- GGPO is a zero-input-latency networking library for peer-to-peer games.checked 9 Oct 2001
- Resimulation
- When received inputs differ from predictions, the game can be resimulated from the point of divergence.checked 9 Oct 2001
- Rollback
- It uses input prediction and speculative execution so gameplay can proceed while remote inputs are in transit.checked 9 Oct 2001
- Sample
- The Vector War sample application demonstrates synchronizing two clients and includes examples for two-, three-, and four-player games.checked 9 Oct 2001
- SDK contents
- The repository contains the SDK code, documentation, and sample applications.checked 9 Oct 2001
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