I really like Processing. Processing is a Visual Programming language, and it is based on Java. It is designed to run either as an Applet, a Standalone App, or as a Java Component; running a Processing Sketch as a Component is the one with less documentation, but probably one of the most interesting and powerful applications of it.
This is a small guide on setting up a Processing Sketch as a Java component, ready to use on your Swing or AWT desktop applications.

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I really like Nodebox. The idea of mixing the Ease of use and Power of Python with the Rendering of Quartz, is simply great. One of my favourite things about it is the great quality of the rendering; it’s just gorgeous.
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