Processing: Creative Coding and Computational Art

The toolbar conveniently contains Processing’s six main control buttons. These buttons
also have equivalent commands in the menu bar, which I’ll cover a bit later. These are not
the only commands in the Processing application, but they are probably the most often
used ones. From left to right, these buttons are Run, Stop, New, Open, Save, and Export.
The following list describes the functions of each (when applicable, I’ve included the Mac
and Windows keyboard shortcuts for each in parentheses after the button name):
Run (Cmd+R on OS X; Ctrl+R on Windows): Compiles your code, launches a display
window, and executes your sketch within this window.
Stop: Terminates your running program, but leaves the display window open.
THE PROCESSING ENVIRONMENT
New (Cmd+N on OS X; Ctrl+N on Windows): Creates a new sketch within a new
project directory. Both the directory and the PDE file (Processing’s own file format)
will share this name. By default, new sketches are saved with the root sketch_, the
date (in the form yy/mm/dd), and a secondary character beginning with the next
alphabetically available character. For example, my current sketch is named
sketch_051024a. If I save this sketch using this name, and then create a new sketch,
that sketch will be named sketch_051024b; the next one will be sketch_051024c.
Be aware that the default preference state in Processing is to delete empty
sketches upon quit. Therefore, if you do not enter any code into the text editor
window, you will not be able to actually save the project to disk—which I guess
makes sense since there’s nothing to save in the file. If you want to change this setting,
you can do so in the preferences, found under the Processing menu in OS X
and the File menu in Windows.
Open (Cmd+O on OS X; Ctrl+O on Windows): Displays a menu that lets you choose
between opening a sketch residing on your local hard drive or across a network,
through a standard file navigator; selecting from a list of available sketches, residing
within your sketchbook location directory; or loading an example sketch that
came bundled with the Processing software, from the examples directory residing
within the main Processing directory. You can set the location of your sketchbook,
where the sketches you create will reside, through the preferences—again found
under the Processing menu in OS X and the File menu in Windows.
Save (Cmd+S on OS X; Ctrl+S on Windows): Writes the current sketch to disk. You
will not be prompted to confirm that you are writing over the previous state. If you
want to keep your original sketch and also save the current one, you should use
Save As, found under File menu. Again, please note that Processing requires sketch
names to begin with a letter or underscore and contain no spaces. You may use
numbers in the sketch name after the initial character, and sketch names should be
no more than 64 characters in length. If you try to name a Processing sketch using
an illegal character, Processing will bark at you and rename your file, converting the
illegal character to an underscore.
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