Why are we scaling the vector water multiplying it by M? Is this just so M looks nicer? Or is this the only way to write it in homogenous coordinates?
SainanChen
I am confused... If we can get (xd/z yd/z d 1)T from (x y z z/d)T, why couldn't we get (xd/z yd/z d)T directly from (x y z)T by multiplying every element by d/z but using matrix multiplication?
wcyjames
@SainanChen: I think there is no easy way to multiply z by d/z directly, since d/z is a term containing z itself. But using homogenous coordinates solves this problem, and many other operations can also be done by matrix multiplications too!
Why are we scaling the vector water multiplying it by M? Is this just so M looks nicer? Or is this the only way to write it in homogenous coordinates?
I am confused... If we can get (xd/z yd/z d 1)T from (x y z z/d)T, why couldn't we get (xd/z yd/z d)T directly from (x y z)T by multiplying every element by d/z but using matrix multiplication?
@SainanChen: I think there is no easy way to multiply z by d/z directly, since d/z is a term containing z itself. But using homogenous coordinates solves this problem, and many other operations can also be done by matrix multiplications too!