The Visualization Toolkit (VTK) is an open-source, freely available software system for 3D computer graphics, image processing and visualization. VTK consists of a C++ class library and several interpreted interface layers including Tcl/Tk, Java, and Python.
Many software engineers recommend what I call the "procrastination approach" to optimization. Delay optimization as much as possible, and don't do it if you can avoid it. I agree with the basic premise. Optimizing too early or too often is not a good appr