vertex positions

Hi!

I am new to Jitter. I am trying to trace the position of an object on the xyz space. I know how to get the position of its center, but say I have a cube, I would like to know where all of the 8 vertexes are at any given moment. I have activated the matrixoutput from the gridshape and when I print the matrix it seems that the vertexes (first 3 values of each line, right?) are immobile despite the cube is actually bouncing around.

Any help?

Thank you

Michele