Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
382
Door class
In designing these really simple classes, it helps to think a little bit about how the house
will fit together. I’ll begin with the door—what properties will the door have? I want to
keep everything really simple for now. The door will have an x position, a y position, width
and height, and a doorknob. What methods will the door have? Working in pure Java, I
would set up a set and get method for each of the properties. For example, for the x property,
I’d have a setX() and a getX() method. In addition, in pure Java, I’d make the
properties private, meaning that users couldn’t call the properties directly (e.g., d1.x), but
would be forced to use the respective set and get methods for each property (e.g.,
d1.getX()). Although this is the classic OOP approach, it is not really the Processing
approach. So I won’t make the properties private, nor will I create set and get methods for
all the properties, which will actually save me a ton of work. The only methods I will add
to the Door class are setknob() and drawDoor(). The setknob() method will control the
side of the door on which the doorknob is drawn, and the drawDoor() method will draw
the door. Here’s the Door class:
class Door{
// instance properties
int x;
int y;
int w;
int h;
// for knob
int knobLoc = 1;
// constants - class properties
final static int RT = 0;
final static int LFT = 1;
// constructor
Door(int w, int h){
this.w = w;
this.h = h;
}
// draw the door
void drawDoor(int x, int y) {
rect(x, y, w, h);
int knobsize = w/10;
if (knobLoc == 0){
//right side
ellipse(x+w-knobsize, y+h/2, knobsize, knobsize);
}
else {
//left side
ellipse(x+knobsize, y+h/2, knobsize, knobsize);
}
}