[vtkusers] vtkCubeSource code question

[David Doria]

On Thu, Nov 5, 2009 at 8:04 AM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
> 1) It creates 24 points and 6 cells (not 6 points and 24 cells as you
> stated). Each cell is a quad and corresponds to each face of the cube.
>
> 2) Each face (cell) has its own set of points because each point will
> have its own normal and texture coordinate. A point can only have a
> single normal or texture coordinate. Each point normal is "normal" to
> the face it belongs to. If the cells shared the corner points, then a
> rendered cube would appear to have flat faces.
>
> 3) The order of the points defining a cell is consistent so that each
> cell is numbered in a counterclockwise ordering when viewed from the
> outside. Draw a picture to understand.


Anja,

>From Bill's #3 - in fact, draw a nice picture (maybe using a vector
graphics tool such as Illustrator or Inkscape) and post it to the
mailing list. Then other will understand, too. Maybe we can add it to
the documentation somehow?

Thanks,

David