Hello.

I have been studying the concept of projection matrix and I found something missing from it.

The projection matrix is supposed to move points into projection space which is enclosed in -1,1 centered at 0,0,0.

The column matrix of projection looks like this

S , 0 , 0 , 0

0 , S , 0 , 0

0 , 0 , Q , 1

0 , 0 , -Zn*Q , 0

It is supposed to transform points from large space of arbitrary world size into -1,1 space, yet, S is a constant and can be precisely 1 for certain angle. It seems that wheather transponed or not, this matrix will not touch the values of x and y, but the x and y are promissed to be in scale of -1,1. How come? This matrix will not translate large points's x and y into -1 , 1. Does projection matrix realy move points into projection space, or additional computaion on vector x and y is neccesary to have them -1,1 spaced? Thanks for clarification.