Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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// abstract method, to be implmented by subclasses
abstract void create();
/* concrete methods*/
//getter/setters
void setColor1(color c1){
this.c1 = c1;
}
color getColor1(){
return c1;
}
void setColor2(color c2){
this.c2 = c2;
}
color getColor2(){
return c2;
}
void setBounds(Rectangle Bounds){
this.bounds = bounds;
}
Rectangle getBounds(){
return bounds;
}
}
Abstract class declaration
Notice that I began the class with the Java keyword abstract. By preceding a class declaration
with abstract, you enforce the rule that the class cannot be instantiated. Therefore,
the call new Gradient() will generate a compiler error. I designed the Gradient class to be
used exclusively as a base class to extend when building custom gradients. To read what
Sun has to say about abstract classes, check out http://java.sun.com/docs/books/
tutorial/java/javaOO/abstract.html.
Class constants
Next, I declared two constants:
final static int AXIS_VERTICAL = 0;
final static int AXIS_HORIZONTAL = 1;
Again, I borrowed some Java modifiers (final and static) to enforce good coding practice.
Constants shouldn’t be changed, and the use of the final keyword ensures that the
compiler enforces this rule. Once a constant has an initial value, you’ll generate a compile
error if you try to assign another value to it. Typically, constants are assigned integer
values, as I did in the Gradient class.
Declaring properties with the static keyword makes their values directly accessible using
the class name, without the use of an object. For example, to access the value of