Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Environment
The Environment section contains ten entries for dealing with (getting or setting) global
environment properties. Three of the entries are function calls (which include parentheses)
for setting environmental properties, such as frameRate() for setting the sketch playback
rate, noCursor() for hiding the cursor, and cursor() for setting the cursor’s icon.
The rest of the entries are for accessing environmental properties—for example, focused
gets the current focus state (true or false) of a sketch (whether the running sketch is the
active application on your desktop); online accesses the sketch’s online status (whether
the sketch is running in a browser—note that the applet can be on your local machine or
a remote server for this property to be true); and screen gets information about the
resolution of your monitor (e.g., screen.width gets the width of your screen).
One somewhat confusing detail in this section is the use of the identical keywords
frameRate() and frameRate. The first is a function call (you can always tell by the inclusion
of the parentheses) for setting the sketch’s frame rate, and the second is a variable
(property) for accessing the current frame rate.
In general, environment properties are connected to what can be referred to as object singletons—objects
representing the mouse, computer screen, Processing program, and so
on—that are the only instance created from their respective class. For example, there may
be a Mouse class defined in your operating system that describes the attributes and behavior
of a mouse. To use the Mouse class, an object of the Mouse class is created. Since there
is (usually) only one mouse connected to your computer, there is only ever one mouse
object at any time—unlike, say, window objects, which are created every time you open a
document. Thus, when you change an environmental variable, its effect is felt throughout
the entire program.
Data
The Data section contains entries that represent the core data types within Processing, as
well as utility functions that allow you to conveniently work with data (such as converting
from one data type to another, manipulating strings, and transforming arrays).
At the lowest level, the computer sees all data as bits (zeros and ones), and couldn’t care
less what each bit stands for. In contrast, we humans, with our limited internal calculating
capabilities, require more complex signs (labels) than bitstrings to be able to remember
and categorize stuff. Data types add logical meaning to the process of coding, allowing us
to express ourselves through programming languages—in a form somewhere between
pure bits and our natural language. For example, even though the statement
String yourName = "Matilda";
is not quite English, it does tell us that the literal name Matilda is being assigned to a variable
called yourName that is of data type String. This is certainly easier to understand than
1101101110000111101001101001110110011001001100001, which is Matilda converted to