What''s OpenGL?

Open Graphics Library.
opengl.org
opengl.org FAQ (first question is "What is OpenGL?")


"There is no reason good should not triumph at least as often as evil. The triumph of anything is a matter of organization. If there are such things as angels, I hope that they're organized along the lines of the mafia." -Kurt Vonnegut


[edited by - wayfarerx on March 22, 2002 4:08:00 PM]

OpenGL is OpenGL

What it is used for? Is it a language?

Again...

opengl.org
opengl.org FAQ (first question is "What is OpenGL?", they have a lot of other info too).

OpenGL stands for Open Graphics Library. It''s a library of functions used to make graphics programming easier and portable. When I say easier, I mean that the majority of OpenGL''s tools are function calls which a lot of beginning programmers tend to find easier than working with the classes and pointers associated with DirectX. OpenGL is supported on multiple operating systems (and to some extent even some consoles). The API is supported by most 3d-hardware acceloraters, making it a very popular for game programming, as well as 3D CAD projects. Probably one of the best tutorial sites I''ve found for OpenGL is:
http://nehe.gamedev.net
Although you can find tons of tutorials through:
www.opengl.org
To give you an idea of the power of OpenGL, all you have to do is look at any Quake game, whose graphics engine is entirely designed on OpenGL framework! I hope this helps to answer your question.

Brandon
bwforres@netzero.net

Wow, thanks. That clears up everything!

In answer to your question "Is it a language?", OpenGL is a library, meaning that you can "call" it''s functions (usually using C or C++) from within your program. You simply link the libraries to your compiler (the libraries should be included if you have any windows based operating system, but if not you can download them from openGL.org), and include the appropriate header files in your program. A snipit of OpenGL code might look something like this:

// Drawing Using Triangles
glBegin(GL_TRIANGLES);
glVertex3f( 0.0f, 1.0f, 0.0f); // Top
glVertex3f(-1.0f,-1.0f, 0.0f); // Bottom Left
glVertex3f( 1.0f,-1.0f, 0.0f); // Bottom Right
glEnd();

The above example would be included in a program that initiallizes an OpenGL window in what ever operating system you''re using, and then would call the function above to draw a simple triangle. the glVertex lines are defining the 3 points of the triangle in a 3 dimensional coordinate system.

Brandon
bwforres@netzero.net