[vtkusers] Display Pointcloud in 3d

[David Doria]

On Fri, Jan 6, 2012 at 4:55 AM, h0ppel <h0ppel at web.de> wrote:
> Hi,
>
> I do have an example point Cloud and put it into imagedata like this:
>
> int i, j, k;
>
>            int[][][] Matrix;
>            var rand = new Random(100);
>
>            var x = 100; var y = 200; var z = 35;
>            var size = x * y * z * sizeof(int);
>
>            Matrix = new int[x][][];
>
>            for (i = 0; i < x; i++)
>            {
>                Matrix[i] = new int[y][];
>
>                for (j = 0; j < y; j++)
>                {
>                    Matrix[i][j] = new int[z];
>
>                    for (k = 0; k < z; k++)
>                    {
>                        Matrix[i][j][k] = rand.Next();
>                    }
>                }
>            }
>
>            vtkImageData image = new vtkImageData();
>
>            image.SetDimensions(100, 200, 35);
>            image.SetSpacing(1, 1, 1);
>            image.SetOrigin(0, 0, 0);
>            image.SetNumberOfScalarComponents(1);
>            image.SetScalarTypeToFloat();
>            image.AllocateScalars();
>
>            unsafe
>            {
>                int* ptr = (int*)(image.GetScalarPointer());
>
>                for (i = 0; i < 100; i++)
>                {
>                    for (j = 0; j < 200; ++j)
>                    {
>                        for (k = 0; k < 35; ++k)
>                        {
>                            *ptr++ = Matrix[i][j][k];
>                        }
>                    }
>                }}< /raw>
>
> but how can I display this cloud in 3d and not only in the viewer?
>
> thanks

I think you are mixing terminology a little bit. If you want a "point
cloud", you should use a vtkPolyData object, then it is very simple to
display:

http://www.vtk.org/Wiki/VTK/Examples/Cxx/PolyData/PointSource

If you create a 3D image (vtkImageData), you will have to use much
fancier display techniques, something like volume rendering.

David