Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Here’s a conditional if...else example:
if (thisBook == bestSeller) {
sleepWellAtNight();
} else {
addMorePictures();
}
Here’s a function example:
void sleepWellAtNight() {
println("one sheep, two sheep...");
}
Here’s a for loop example:
for (int i = 0; i < totalPictures; i++) {
makeSomeInterestingPictures();
}
You’ll be looking at a lot more examples that make use of curly braces shortly. You’ll notice
that I structured the blocks of code between the curly braces using indentations. Indenting
is not necessary for the code to work, but it is the conventional way to write blocks of
code. Indenting makes it easier for other coders to read your code. In the examples in this
book, each indentation is created by hitting the spacebar twice.
Dot syntax
The last syntactical structure you’ll see in Processing is the dot (.) It looks like a period
(and it technically is a period), but it’s referred to as a dot; it’s the same dot in .com. The
dot is an advanced syntactic structure used in OOP.
As I mentioned earlier, there are two approaches to structuring a program in Processing:
procedural programming and OOP. Procedural programming uses functions to organize a
program. You just saw an example of a function in sleepWellAtNight. When you need to
use a function, you explicitly call it—for example, sleepWellAtNight()—pretty simple.
In OOP, you build much more complex structures called classes. To use a class, you create
instances of it, known as objects. Classes contain properties and methods. You can think of
the properties as the traits of the object and the methods as actions you perform on/with
the traits. For example, if you create a class called Cat, some of the properties might be
color, weight, and markings, and a method might be getBreed(). You use the dot syntax
as a way to connect an object with its properties and/or methods. For example, if you
create an object myCat from the Cat class, the object can call the getBreed() method
using dot syntax, like this:
String breedName = myCat.getBreed();