Contour filter: accelerate for linear grid inputs
Use vtkContour3DLinearGrid when possible
vtkContour3DLinearGrid can be used when the following conditions are met:
- all cells in the input are linear (i.e., not higher order)
- the contour array is one of the types supported by the vtkContour3DLinearGrid
- the Compute Scalars option is off
Edited by Cory Quammen