where is 0,0,0 in 3d space

Guys where is 0,0,0 in the window, is it bottom left, as i think 0,0 is, or is it in the middle???

Or am i well off, can i define my own 0,0,0 default starting points.

Thanks.

It depends on how you set up your matrixes. Using a standard perspective matrix for the projection and the identity for the modelview, the point at world coordinate (0, 0, 0) is projected exactly into the middle of the screen.

Y.