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edits
Changes
→DOM Integration?? (need a better header)
Processing.js is more than just a Processing parser written in JavaScript. It is designed in a way that connects the Processing language (also known as P5) with web technologies such as JavaScript, the HTML5 canvas element, JQuery, and various web services. Furthermore, Processing.js is built in such a way as to allow easy integration of new technologies as they emerge.
The original Processing Language is Java based. In order to To run processing code a Processing sketch in a web page , the Java code has to be completely converted into JavaScript. While syntactically JavaScript and Java are fairly similar, there are some fundamental differences that has made this conversion challenging. Each The first is that we wanted to do this conversion dynamically in real time. The code produced by the converter needed to be fully object oriented and we had to provide support to all native Java functions and objects (such as Strings) that are supported by Processing. We also had to take into account the differences between working with web resources vs local resources. Furthermore we had to consider how we would handle some fundamental differences between Java and JavaScript such as typed vs. typeless variables, function overloading and variable name overloading. From it's inception, Processing.js was designed to be more than just a rewrite of the Java functions provided by Processing to JavaScript. John Resig wrote the original Processing.js parser to scan the code in a Processing sketch for hints of Java code and convert that uses processingcode to JavaScript. However, if the parser encountered JavaScript code, it would leave the code intact. This method allowed not only for the conversion of existing Processing code to JavaScript but the injection of JavaScript into Processing sketches as well. By not only
We could of done a straight up JavaScript port of the Processing language, but that would mean all Processing sketches written in Processing, would need to be rewritten in JavaScript. This way, all previous Processing sketches can simply be dropped into the web, and they will work. We took this one step further, allowing both languages to mingle as one. When we parse the Java into JavaScript, we don't break previously existing JavaScript, this means you can add JavaScript right into the Java, without having to declare that you are doing so. We simply ignore the JavaScript we encounter while parsing the Java, leaving it in tact. Not only do we allow mingling of the two languages, which is unique and powerful in itself, but also allows for sketches to be written in pure JavaScript. The advantages of this is we had a huge library of work to test and draw from right from the beginning.
