Re: OpenGL question

On 2008-01-20, Bin Chen <binary.chen@xxxxxxxxx> wrote:

Many operations of opengl is multiply the current matrix with a
provided matrix. But what is the current matrix for?

I suggest you do some reading on computer graphics, before trying to use
OpenGL.

OpenGL works as a typical rendering pipeline. Vertices are fed to it in
model space (say a coordinate system somewhere about the center of each
object) and then, they are sucessively transformed through a number of
coordinate systems, in order to be finally projected to the 2D view
plane and drawn on the screen. A 4x4 matrix is needed for each such
transformation, which you can manipulate with the OpenGL matrix
functions.

This is not the best newsgroup for OpenGL discussions. OpenGL was born
on UNIX systems, but it's a cross-platform API, and there is a special
newsgroup for it: comp.graphics.api.opengl. Post any other questions
you may have, there.

--
John Tsiombikas (Nuclear / Mindlapse)
http://nuclear.sdf-eu.org/
.

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