rougier/freetype-gl
FreeOpenGL text using one vertex buffer, one texture and FreeType
FreeFree tier
Inputs: text
About rougier/freetype-gl
Freetype-gl is a small C library for displaying Unicode text in OpenGL using a single texture and a single vertex buffer. It integrates with FreeType to load fonts and generate bitmap glyphs, which are packed into a texture atlas using the skyline bottom left algorithm. The library provides optional modules for markup text styling, font caching, generic vertex buffers, and distance field computation for smooth rendering. Designed for efficiency and cross-platform use, it works on Windows, Linux, macOS, and Android.
Key Features
Single texture and vertex buffer for efficient OpenGL text rendering
Full Unicode support via FreeType
Texture atlas with skyline bottom left packing algorithm
Optional components: markup, font-manager, vertex-buffer, distance fields, makefont
Cross-platform C library (Windows, Linux, macOS, Android)
MIT-licensed open source code
Pros & Cons
Pros
- Efficient rendering with minimal draw calls (one buffer, one texture)
- Full Unicode and international text support
- Open source with permissive MIT license
- Cross-platform across major desktop and mobile OSes
- Active community with 1.7k GitHub stars and many contributors
Cons
- Limited to OpenGL (no DirectX/Vulkan support)
- C codebase requires manual memory management
- Documentation is primarily the README and inline comments
- No built-in text layout beyond simple string rendering
Best For
Rendering text in OpenGL applicationsGame UI and HUD text displayScientific visualization labels2D text overlays in OpenGL-based toolsPrototyping text rendering in graphics engines
FAQ
What is freetype-gl?
Freetype-gl is a C library that renders Unicode text in OpenGL using a single texture and a single vertex buffer, leveraging FreeType for font handling.
What are the main dependencies?
The library requires FreeType and OpenGL. It also uses CMake or Meson for building.