Based on Rudolf Olah's version and modification by Bunny Blake.
https://github.com/emacsmirror/processing-mode
https://gist.github.com/4083326
The snippets are taken from Sublime Text 2's Processing plugin and converted to yasnippet snippets.
In your .emacs file, add this:
(add-to-list 'load-path "/path/to/processing2-emacs/")
(autoload 'processing-mode "processing-mode" "Processing mode" t)
(add-to-list 'auto-mode-alist '("\\.pde$" . processing-mode))
To add the snippets put this also in your .emacs file:
(yas-load-directory "/path/to/processing2-emacs/snippets")
and eventually add this to activate yasnippet if it is not:
(add-hook 'processing-mode-hook 'yas-minor-mode)
The key-bindings are:
C-c C-r Run a sketch.
C-c C-b Compile a sketch into .class files.
C-c C-p Run a sketch full screen.
C-c C-e Export sketch.