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Revision as of 18:16, 11 August 2008 by Henk-Jan van Tuyl (talk | contribs) (Added "Beautiful Code" to the resources section and changed some texts to links)

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This is a stub page for Haskell's OpenGL and GLUT bindings. It is meant as a starting point to replace the outdated and misleading documentation at the old page.

First, note that the implementation is far more up-to-date than that old page suggested (originally, it was quite useful, but the page hasn't kept up with the implementation for a long time now).


In particular, note that the examples/ directory in the GLUT repo contains lots of examples, including translations of the red book examples.

Both the API documentation and the examples are best studied with the original specs and the original red book examples at hand. An index of the examples from v1.1 of the red book, with screen shots, can be found here

Projects using the OpenGL bindings

  • Frag, a 3D first-person shooter game.
  • Monadius, a 2D scrolling arcade game.
  • Roguestar, a roguelike adventure game using 3D graphics.
  • Shu-thing, a 2D scroling arcade game.
  • Topkata, a jumping ball puzzle game.
  • PolyFunViz, a toolkit for scientific visualization (e.g. surfaces, flows, contours, volumes)

HOpenGL Resources

OpenGL Resources

Getting Started

  • assuming you know Haskell, any OpenGL tutorial of your choice should get you going (browsing the OpenGL site is also a good idea)
  • use the Red Book, and its example code translations, to understand the small differences between OpenGL and HOpenGL
  • use the OpenGL and GLUT specs to find your way around the HOpenGL Haddock documentation
  • use the HopenGL list for questions and success stories


I can't display text with renderString

It's probably because the text is displayed too big. Setting a much smaller scale factor before calling renderString should solve the problem.

scale 0.001 0.001 (0.001GLfloat)
renderString Roman "Test string"

Animations flicker

If you're not using DoubleBuffered display mode, turn that on. Also, you must set the display mode before creating the window you're going to be drawing in. To check if you've enabled double buffering use something like:

db <- get doubleBuffered

and set DoubleBuffered mode (before creating your windows!) like this:

initialDisplayMode $= [DoubleBuffered]
createWindow "My Window"
You will also need to call
at the end of your draw function.