egui (pronounced “e-gooey”) is a simple, fast, and portable immediate mode GUI library written in Rust. It is designed to provide an easy-to-use interface for creating graphical user interfaces (GUIs) in Rust applications.
Whether you are building a web app, a desktop application, or integrating a GUI into a game engine, egui offers a versatile solution. Below, we explore its tools and functionality.
Key Features Of egui
- Immediate Mode GUI:
eguioperates on the immediate mode paradigm, which means the GUI is redrawn every frame. This approach eliminates the need for callbacks or retained states, simplifying the code structure. For example:
if ui.button("Click me!").clicked() {
println!("Button clicked!");
}
- Cross-Platform Compatibility:
eguiis highly portable and works seamlessly across platforms such as Web (via WebAssembly), Linux, macOS, Windows, and Android. The official framework,eframe, facilitates this compatibility. - Widgets and Layouts:
eguiprovides a variety of widgets like buttons, sliders, checkboxes, text fields, color pickers, and more. It also supports flexible layouts—horizontal, vertical, columns, and automatic wrapping. - Customizability:
Developers can customize the appearance of GUIs through styles that allow changes to colors, fonts, spacing, and sizes. This makes it easier to adapt the GUI to specific design requirements. - Integration-Friendly:
eguican be integrated into existing game engines or platforms due to its modular design. It only requires textured triangle rendering to function. - Lightweight and Safe:
With minimal dependencies and no use of unsafe Rust code,eguiensures safety while maintaining performance.
Advantages Of Using egui
- Ease of Use: Its immediate mode simplifies GUI programming by removing complexities like state synchronization and callback management.
- Performance: Designed for responsiveness at 60 frames per second in debug builds.
- Extensibility: Developers can create custom widgets or extend functionality as needed.
While egui is easy to use and versatile, it does have some drawbacks:
- Layouting complex GUIs can be challenging due to the immediate mode approach.
- It lacks native-looking interfaces and some advanced features found in retained mode libraries.
egui is an excellent choice for Rust developers seeking a straightforward way to build GUIs for interactive applications or games.
With its focus on simplicity, portability, and customization, it empowers developers to create responsive interfaces efficiently while maintaining code clarity.















