I wrote an [overview] almost eight years ago about IDL's basic routines to visualize a vector field. Not much has changed since then. This [paper] by Laidlaw, et al, mentioned at the end of my overview, outlines six common visualization techniques and evaluates them on the speed and accuracy of doing common tasks with them.

I think it would be great to have two of the better performing techniques: OSTR (image-guided streamlines, integral curves) and LIC (line-integral convolution) techniques. Between the two of them, they have the best or nearly the best performance in every category. An example OSTR visualization is shown below:

OSTR example

I have tackled LIC and have [code][LIC code] to produce images from vector fields in my library.

[overview]: http://michaelgalloy.com/2008/03/19/overview-of-flow-visualization-in-idl.html "Overview of flow visualization in IDL"

[paper]: http://www.cs.utah.edu/~kirby/Publications/Kirby-10.pdf "Comparing 2D Vector Field Visualization Methods: A User Study"

[LIC code]: http://michaelgalloy.com/2008/04/10/line-integral-convolution-code.html "Line-integral convolution code"