About this page.
The purpose of this page, and the other pages in this tree is to
provide a foundation for learning and using OpenGL.
Much of information on the web assumes knowledge which a student may not have.
I do not endorse any hardware vendor.
What is OpenGL ?
OpenGL is the defacto
standard for acclerated
cross-platform interactive graphics.
That is, if you need to write a program that takes advantage
of modern GPU hardware, and that program needs to run on
Windows, Mac OS X, and Linux then OpenGL is a good choice for you.
Most high end cell phones also have a GPU inside them which is exposed
to the programmer with OpenGL. The OpenGL standard itself is part of a family of multimedia
standards administered by an industry consortium called
The Khronos Group .
How do I write an OpenGL program?
Because OpenGL is meant to run on any operating system, OpenGL (or GL)
has no notion of a window. Therefore, each operating system must have
an API which can setup a window so that OpenGL drawing calls will
work in that window. On UNIX/Linux that API is called GLX. On Windows
that API is called WGL, and on Mac OS X, that API is called AGL.
There are OpenGL bindings for Java also.
Of course, after opening a window, we'd like to get keyboard
and mouse events also. These calls are operating system specific also.
Further, if we're writing software that's supposed to function across
multiple operating systems, we'd like all those platform specific calls to
be abstracted away to generic event callbacks anyway. Fortunately,
toolkits that do just this job are available. Here are a few
I do not evaluate these libraries in terms of their suitability for
any particular application domain here. That is up to you. Rather,
I mention them because I have used them all and they all provide
a reasonable way of abstracting the operating systems services
required, namely: opening an OpenGL window and getting events
of various kinds (e.g. keyboard and mouse events). They are also
all open source, so they can be used at no cost. Notably, GLUT
is not free, but a free alternative exists here:
Hardware vendors write drivers which
allow programmers to use their GPU by making OpenGL calls.
So, in addition to having operating system support for OpenGL,
(or, as with the libraries above, an abstraction of those services)
your GPU driver must support it. Fortunately, all major hardware
There are OpenGL bindings for many languages, but I will focus on
C/C++ since those are the most widely used. Once you are familiar
with OpenGL, transferring that knowledge to Java or Python
should be straight forward.
- The OpenGL Web Site The Official web site for the standard. News and documentation are there. Worth special mention are the on line reference pages which are complete for OpenGL 2.1. OpenGL 3.2 versions are in the works.
- Paul's Projects A wide variety of well written tutorials relating to OpenGL and other technical topics.
- Lighthouse 3D , many tutorials and examples relating to OpenGL.
- NeHe , also many tutorials and examples relating to OpenGL.
- Paul Bourke's Web Pages An astonishingly rich web site filled with information spanning many areas of computer graphics and science.
- The OpenGL Programming Guide Also known as "The Red Book". This is the cannonical reference for OpenGL programmers.
- The OpenGL Shading Language . Also known as "The Orange Book". This is the cannonical reference for the OpenGL shading language, or GLSL.
- The OpenGL Book List . The book list on the OpenGL web site. To my knowledge, its a fairly complete list of major OpenGL related texts.
A math professor of mine used to repeat the phrase "many examples"
quite often. He used many examples. I learned quite a lot from him,
so I will adopt that approach here.
All the examples I show use the GLUT toolkit. It is well
suited for teaching and it is the lingua franca of the
OpenGL world. That is, when reading books or talking with other
developers, knowledge of GLUT is assumed. GLUT is quite easy
to use. Makefiles for Linux are provided.