[vtkusers] Why is my render slow, rendering in software mode?

[Todd Gable]

I made a small program to load some volume data and render it using vtkVolumeRayCastMapper and the rendering is extremely slow. I was also playing with VolView and the rendering and interaction was very fast for the same data. While I was playing with the VolView option I ran into a check box that forced hardware rendering off and the results were very similar to default behavior of my VTK app. After I searched around the only info I could find was that opengl will uses hardware first unless the data format is unsupported. Both VolView and my VTK volume render app are using the same unsigned short .vtk volume data. 

Hardware is a P4 with a 9800 Pro on WinXP.


Todd Gable