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mikau
07-20-2005, 10:45 PM
According to the info I can just install it off a website. :eek: Don't I have to pay for it?

And btw, does OpenGL include any 3D modeling and animation tools? Or do you need to draw the models and animations elsewhere and import them into openGL?

Ehsan Kamrani
07-20-2005, 11:10 PM
OpenGL is open source and it's free. Download the latest version of your video card and download its OpenGL SDK. Each hardware-NVIDIA or ATI- uses from its driver and implementation to support the OpenGL API.

OpenGL cantains of some simple SYMBOLIC CONSTANTs and functions to draw the simple objects--points, lines, squares, triangles, etc.You can put these shapes together and create more complex objects.Also with OpenGL quardics you can draw more complicated shapes-Spheres, cones, etc. But GLU Quadric isn't a good way to do graphics. processing the quadrics is so expensive for the processor.
And yes. it's better that you load the complicated objects and then animate them with OpenGL. It's possible...
Hope that you can understand my bad english ;)
-Ehsan-

jide
07-21-2005, 12:43 AM
OpenGL is not open source. It is open in the sense that anyone can see its architecture (with the ARB) and can tell ideas about its future (threw this web site). So OpenGL is not free at all.

However there is (are) free implementations of OpenGL like Mesa (for Linux/Unix). Nevertheless free implementations usually lack of hardware acceleration due to the fact that graphic vendors do not open their architecture (I don't mean it's bad or good).

OpenGL is a set of 2 libraries only (gl and glu). So, don't expect for any providen modeler and such with it. So, you'll have to model from a modeler (like 3DS Max or Blender...) and then import them in your program. Most common model format are well explained in many places on the Internet (like 3ds and so).

Hope that helps.

ZbuffeR
07-21-2005, 12:54 AM
Originally posted by Ehsan Kamrani:
OpenGL is open source and it's free.OpenGL is not open source. The API is open and usable freely, but actual implementations (from ATI, NVidia, 3dlabs etc) must be licensed by SGI.
Only one exception is mesa (http://mesa3d.sourceforge.net/) : it is an open source implementation in software of a 'compatible' api but is not an official licensed implementation.

EDIT: too slow...

V-man
07-21-2005, 06:24 PM
Originally posted by jide:
OpenGL is not open source. It is open in the sense that anyone can see its architecture (with the ARB) and can tell ideas about its future (threw this web site). So OpenGL is not free at all.

However there is (are) free implementations of OpenGL like Mesa (for Linux/Unix). Nevertheless free implementations usually lack of hardware acceleration due to the fact that graphic vendors do not open their architecture (I don't mean it's bad or good).

OpenGL is a set of 2 libraries only (gl and glu). So, don't expect for any providen modeler and such with it. So, you'll have to model from a modeler (like 3DS Max or Blender...) and then import them in your program. Most common model format are well explained in many places on the Internet (like 3ds and so).

Hope that helps.OpenGL is *not* a set of 2 libraries. OpenGL is OpenGL and GLU is the "OpenGL Utility".
It is written to make GL programming easier.
There is also GLUT which is the "OpenGL Utility Toolkit", also for making GL programming easier.

There are countless other libs out there that make GL programming easier. Non of them are part of the OpenGL specification.

What is the GL specification?
It defines GL functions and it's pipeline in a generic way. It can be used to write your own implementation, either software or hardware.

http://www.opengl.org/documentation/spec.html

That's what GL is. It is a specification. It is "Open" for all to see and read.