I have a NetCDF file with multiple time points in it and I program in vtk python. After loading the NetCDF file in paraview, I am able to navigate through all the available time points without any delay. However, I am not able to achieve the same performance in vtk. All I want is to switch the scalar array for which I am using the following statement.
timestep = 162152
reader.GetOutputInformation(0).Set(vtk.vtkStreamingDemandDrivenPipeline.UPDATE_TIME_STEP(), timestep )
After issuing this statement, if I try to get the output from the netCDF reader, I am able to get the new scalar array for the time step 162152, but I have a performance issue in vtk because I always render the scalar data on a surface generated from the netCDF file. (code below)
reader = vtk.vtkNetCDFCFReader()
reader.SetFileName(filePath)
reader.UpdateMetaData()
reader.SphericalCoordinatesOn()
reader.ReplaceFillValueWithNanOn()
reader.Update()
cellDataToPointData = vtk.vtkCellDataToPointData()
cellDataToPointData.SetInputData(reader.GetOutput())
cellDataToPointData.ProcessAllArraysOn()
cellDataToPointData.PassCellDataOn()
goemetryFilter = vtk.vtkGeometryFilter()
goemetryFilter.SetInputConnection(cellDataToPointData.GetOutputPort())
goemetryFilter.Update()
self.mapper = vtk.vtkPolyDataMapper()
self.mapper.SetInputData(goemetryFilter.GetOutput())
self.mapper.GetInput().GetPointData().SetActiveScalars("elevation")
self.mapper.SetColorModeToMapScalars()
self.mapper.ScalarVisibilityOn()
self.mapper.Update()
I am now wondering how paraview is able to switch different time steps so fast and what should I do to quickly switch scalars in vtk-python for the above code? Any input on this is greatly appreciated. Thanks in advance!