Table of Contents
Table of Contents
Pros & Cons
When you need to create a graphical representation of someth
ing for whatever
reason on a computer you need to use a graphics API. OpenGL is the industry standard
graphics API. OpenGL allows the use of common and complex graphics rendering, in a
fairly simple, cross
Because OpenGL is created by a
pool of top
graphics and computer companies, it allows the creation of applications that look and act
the same on different operating systems.
One of OpenGL’s biggest advantages is
ability to create a graphics application that works on most operating
systems. OpenGL is
also well documented and fairly easy to learn
to program when compared to other
OpenGL is a multipurpose, multiplatform graphics API
. Silicon Graphics Inc originally created
since 1992 OpenGL’s
development has been overseen by the OpenGL Architecture Review Board. This board
is made up from major graphics vendors, and major computer related companies such as
NVIDIA, ATI, Hewlett
Packard, Dell, Intel, Matrox, IBM, 3DLa
bs, Evans & Sutherland,
SGI, Sun Microsystems, and Silicon Graphics.
The board determines and maintains
OpenGL’s specifications. The latest version of OpenGL is 2.0 which was just released
OpenGL is a collection of functions that give access t
o all of the features offered by
graphics hardware. There are hundreds of functions within OpenGL.
Using the OpenGL
API allows you to change various aspects such as current c
olor, blending, lighting, ect.
The core of OpenGL is the rendering pipeline. W
hat appears on the screen is a result of
this pipeline. OpenGL handles most of these steps for you. You can modify the
operations, but the operations at each step are always the same unless you modify them.
enGL allows rendering, texture mapping, spec
ial effects (such as fog), lighting, and
: The OpenGL pipeline
OpenGL does not support input, windowing or menus
for any operating system
In order to get those kinds of functionality y
ou need to use an extended function library
(also known as an extension)
. One of the most important of these
(OpenGL Utility Toolkit). GLUT provides the input, windowing, and menu functionality
while keeping OpenGL platform independent.
There are also other libraries out there
such as SDL, and G
ee. SDL (Simple Direct Media Layer) provides cross
support for audio, 2D graphics, and many more functionalities.
GLee (OpenGL Easy
) provides functions for W
OpenGL programs are created by using C/C++ to program them. Although they
use C/C++, OpenGL has
own list of commands that are unique to it.
program can bee seen below.
OpenGL is used for a wide variety of graphics applications. Most commonly it is
used for gaming, and computer graphics.
“Any visual computing application requiring maximum performance
3D animation to CAD to visual simulation
performance OpenGL capabilities. These capabilities allow developers in
diverse markets such as broadcasting, CAD/CAM/CAE, entertainment,
medical imaging, and virtual reality to produce and display incredibly
compelling 2D and 3D gr
Pros and Cons
One of the biggest advantages of using OpenGL is that
it is the industry standard
for graphics specification. This allows OpenGL to be multiplatform, and vender neutral.
Another advantage is that any changes to OpenGL are overse
en by the ARB to insure
backwards compatibility of older programs, and allows developers enough time to adopt
to any changes made to it. Any OpenGL application is visually consistent when used on
different hardware and operating systems. OpenGL is also o
ne of the easiest API’s to
program, and it is very well documented.
When it comes to programming OpenGL allocations for Windows, using certain
libraries make the application only work on Windows. This eliminates the major
advantage of OpenGL being multi
Open GL Vs. Direct
Multiple Operating Systems
Hardware Independent Z
Depth of Field
Parametric Curves and Surfaces
Hardware Not Present
Let App. Determine
: OpenGL Features, and Direct
Astle, Dave, and Hawkins, Kevin.
Beginning OpenGL Game Progra
“OpenGL Overview.” Article. Nov 29, 2004.
For more information on Open
documentation of OpenGL
For more information on
For more information on GLUT:
For more information on SDL:
For more information on Glee:
re information on Direct