Q:

Difference between Vector4f and Vector3f java3d

Can anyone explain me the difference between vector3f and vector4f
i know that vector3f contains of xyz
however a vector4f contains xyzw
but what if I want to convert 3f to 4f what value i put for w as? 

A:

if you don't use the fourth value, set it to zero. 
there is a constructor for vector4f that takes a Tuple3f, and what that constructor does is set the W value to 0. 
Vector3f vector3 = new Vector3f(x,y,z);
Vector4f vector4 = new Vector4f((Tuple3f)vector3);

