I'm looking at the 2 gradient filters available in the ParaView GUI and trying to improve their functionality. I see that the "Gradient of Unstructured DataSet" filter only works with vtkPointSets in ParaView but in general can handle vtkImages and vtkRectilinearGrids as well. The Gradient filter only works on image data. This means that there is on gradient filter for rectilinear grids and that any multiblock data set with mixed data set types can't be used with the gradient filter either. Because of this I'm wondering why the Gradient of Unstructured DataSet filter was limited to just vtkPointSets. Obviously performance is an issue. On an image data with 100 million cells, 1000 by 1000 by 100 whole extent, it took 14.5 seconds to create the image data with the wavelet source and run the Gradient filter. Using the Gradient of Unstructured DataSet filter instead it took 41.9 seconds. <br>
<br>The Gradient of Unstructured DataSet does have more functionality (operates on arrays with more than a single component, can calculate vorticity,...) but I'd like to look into getting a better interface to gradients and am trying to encourage input on that process.<br>
<br>Thanks,<br>Andy<br><br>