Modify the execution speed of Windows games by hooking system time functions via a desktop interface.

OpenSpeedy is an open-source desktop app that functions as a game speed modifier for Windows. It allows users to manipulate the execution speed of game processes, enabling them to either accelerate or decelerate the pace of gameplay. The application is designed for Windows 10 and newer versions, and it is available for installation via the Winget package manager or through a manual download of the executable.
Users operate the software by launching the application and selecting a running game process from the provided list. Once a target process is selected, the speed multiplier is adjusted through the interface to change the game pace in real time. The tool is compatible with both x86 (32-bit) and x64 (64-bit) architectures, ensuring it can interact with a wide variety of desktop games regardless of their bitness.
The application is built using Rust and the Tauri framework for the GUI, utilizing MUI and Ant Design for its visual components. It achieves speed modification by hooking several Windows system time functions across user32.dll, winmm.dll, and kernel32.dll. Specifically, it intercepts functions such as QueryPerformanceCounter, GetTickCount, GetTickCount64, and Sleep to manipulate how the target process perceives the passage of time. By overriding these specific API calls, the software can trick the game engine into running faster or slower without requiring deep system kernel access.
This tool is intended for educational and research purposes in game modification and development. It is a lightweight utility for users who need to modify game timing without the complexity of a full memory editor.
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