Things you need to know about the code presented in this blog.

• it is compatible with Processing V3
• where sensible I use object orientated programming (OOP) techniques, primarily basic classes and objects. Processing provides a beginners tutorial on objects so if you are not familiar with OOP then read the tutorial.
• most user defined classes shown are inner classes so have access to the fields in the containing class. Although  this is not good OO design it reduces the syntax complexity .
• where top-level classes are created they will be in standard Java syntax and can be used in other IDEs such as Processing without alteration.
• the code is likely to be verbose. The reason is to make the meaning (semantics) absolutely clear. As far as I am concerned understandable code is one of the most important attributes of good software. If you don’t think so then good luck updating that program you wrote last year.
• if the code needs resources such as images or sounds then a link will be provided to download them in zip format.