From:
Posted: Sunday, July 13, 2008 3:00 AM
Subject: Calculating listener's orientation from pitch, yaw and roll angles?
So the values should range from -1 to 1?
They're standard directional vectors. Each value has the range -1 to 1, but the entire length of the vector equals 1. You get the length with:
length = sqrt(x*x + y*y + z*z)
Use that with the default forward vector (0,0,-1), and we get:
sqrt(0*0 + 0*0 + -1*-1) = sqrt(0+0+1) = sqrt(1) = 1
Thus the vector has a length of 1. Applying a proper rotational matrix to a vector will produce another vector that has the same length (though the actual x,y,z values may be different).