clip polygonal data with user-specified implicit function or input scalar data vtkClipPolyData is a filter that clips polygonal data using either any subclass of vtkImplicitFunction, or the input scalar data. Clipping means that it actually “cuts” through the cells of the dataset, returning everything inside of the specified implicit function (or greater than the scalar value) including “pieces” of a cell. (Compare this with vtkExtractGeometry, which pulls out entire, uncut cells.) The output of this filter is polygonal data. To use this filter, you must decide if you will be clipping with an implicit function, or whether you will be using the input scalar data. If you want to clip with an implicit function, you must: 1) define an implicit function 2) set it with the SetClipFunction method 3) apply the GenerateClipScalarsOn method If a ClipFunction is not specified, or GenerateClipScalars is off (the default), then the input’s scalar data will be used to clip the polydata. You can also specify a scalar value, which is used to decide what is inside and outside of the implicit function. You can also reverse the sense of what inside/outside is by setting the InsideOut instance variable. (The cutting algorithm proceeds by computing an implicit function value or using the input scalar data for each point in the dataset. This is compared to the scalar value to determine inside/outside.) This filter can be configured to compute a second output. The second output is the polygonal data that is clipped away. Set the GenerateClippedData boolean on if you wish to access this output data.