GuiLite — Smallest Header-Only GUI Library for All Platforms

Introduction

GuiLite is a header-only C++ GUI library compressed into roughly 4,000 lines of code. It targets extreme portability, running on microcontrollers, Linux framebuffers, Windows GDI, and Docker containers with no external dependencies.

What GuiLite Does

• Provides basic widgets: buttons, labels, lists, keyboards, and wave displays
• Renders directly to raw pixel buffers on any platform
• Supports multi-layer compositing for overlapping UI elements
• Works on MCUs with as little as 32KB RAM
• Enables cross-platform development from embedded to desktop with one codebase

Architecture Overview

GuiLite operates on a simple display-surface-widget model. A display manages one or more surfaces (pixel buffers). Widgets draw themselves onto surfaces using direct pixel manipulation. There is no scene graph or layout engine; positions are set explicitly for maximum control and minimal overhead.

Self-Hosting & Configuration

• Copy the single header file into your project; no build system changes needed
• Implement a platform-specific display driver (framebuffer, GDI, or custom)
• Set screen resolution and color depth at compile time
• Example projects available for STM32, Raspberry Pi, and Windows
• Use Docker samples to preview UI without hardware

Key Features

• Entire library fits in one 4K-line header file
• Zero external dependencies — no SDL, Qt, or OS-specific APIs required
• Runs on ARM Cortex-M, RISC-V, x86, and MIPS architectures
• Multi-language support through Unicode rendering
• Animation and transition support for responsive UIs

Comparison with Similar Tools

• LVGL — richer widget set and theme engine but larger footprint; GuiLite is smaller and simpler
• Dear ImGui — immediate-mode paradigm for desktop tools; GuiLite targets embedded displays
• Qt for MCUs — commercial solution with more features; GuiLite is free and dependency-free
• Slint — modern declarative UI in Rust; GuiLite stays pure C++ header-only

FAQ

Q: How small is the compiled binary? A: A minimal GuiLite app compiles to under 10KB on ARM Cortex-M, depending on widget usage.

Q: Does GuiLite support touch input? A: Yes. It handles touch events and routes them to widgets; you provide the platform-specific touch driver.

Q: Can I use GuiLite for desktop applications? A: Yes. There are examples for Windows, Linux, and macOS using native display backends.

Q: Is GuiLite suitable for production embedded products? A: It is used in commercial IoT devices, medical instruments, and industrial panels where minimal resource usage matters.

Sources

• https://github.com/idea4good/GuiLite
• https://gitee.com/aspect-studio/aspect-guilite