From the website
Processing is an open source programming language and environment for people who want to create images, animations, and interactions. Initially developed to serve as a software sketchbook and to teach fundamentals of computer programming within a visual context, Processing also has evolved into a tool for generating finished professional work. Today, there are tens of thousands of students, artists, designers, researchers, and hobbyists who use Processing for learning, prototyping, and production.
- Free to download and open source
- Interactive programs using 2D, 3D or PDF output
- OpenGL integration for accelerated 3D
- For GNU/Linux, Mac OS X, and Windows
- Projects run online or as double-clickable applications
- Over 100 libraries extend the software into sound, video, computer vision, and more…
With advances in graph databases, visualization techniques, availability of data, etc., now is a great time to be working with topic maps.