Hi. I was just wondering what exactly the functions in opengl were to translate/rotate a vertex by opengl''s current matrix, and actually get the results back. AKA Without having that point rendered, and actually recieving the coordinates of the vertex in the current matrices space. Obviosly, the glVertex3f and likewise functions dont return anything and beyond that are used only for rendering. Not for actually putting a vertex into matrix space. Incase you dont know what Im talking about, say I have a point at (1,1,1) and I had a 3 dimensional matrix: (1,0,0)(0,1,0)(0,0,1) if I wanted to put the point into matrix space, I would multiply the point by the matrix. In this example, as the matrix is an identity matrix, the resulting point would be at (1,1,1) as 1 x = 1x,0y,0z and likewise for the rest. Very obvios is the fact that opengl has facilities for doing this. Otherwise it would be slightly impossible to render, well, anything. It doesnt make any sense to me that opengl would have the math functions to rotate/translate vertecies by matrices built in, but not allow the users (erm, coders that is) to utilize them. Ive checked all of my books, and cant find opengl''s facilities for doing this. Im quite sure they exist though. If you know anything about this, it would be really helpful. Thanks in advance. ~Elig

i think what you are looking for is "glFeedbackBuffer". check it out.

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