On Fri, 8 Jul 2005, Keean Schupke wrote: > Okay, this approach is starting to make sense to me... I can see now > that Vectors are a different type of object to Matrices. Vectors > represent points in N-Space and matrices represent operations on those > points
That's what I wanted to express. > (say rotations or translations)... But it seems we can represent > translations as adding vectors or matrix operations (although we need to > introduce the 'extra' dimension W... and have an extra field in vectors > that contains the value '1'). > > (3D translation) > > [x,y,z,1] * [[0,0,0,0],[0,0,0,0],[0,0,0,0],[dx,dy,dz,dw]] = > [x+dx,y+dy,z+dz,1+dw] Do you mean [x,y,z,1] * [[1,0,0,0],[0,1,0,0],[0,0,1,0],[dx,dy,dz,dw+1]] ? > but how is this different from adding vectors? If we allow vector > addition then we no longer have the nice separation between values and > linear operators, as a value can also be a linear operator (a > translation)? ??? _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
