Without any VI or example it would be very hard to support you
On our homepage you can find this example:
Your VI and a little more precise description would help to find a solution.
You can find some examples here:
C:\Program Files\National Instruments\LabVIEW 2010\examples\picture\3D Picture Control\Using Meshes.vi
Refer to the Using Meshes VI in the labview\examples\picture\3D Picture Control directory for an example of using the New Light VI.
or LabVIEW example finder or in the LabVIEW Help when you are looking for "New Light VI"
Hope that helps