topical media & game development
#javascript-processing-example-basic-objects-inheritance.htm / htm
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<html><head>
<script src="javascript-processing-example-processing.js"></script>
<script src="javascript-processing-example-init.js"></script>
<link rel="stylesheet" href="javascript-processing-example-style.css">
</head><body><h1><a href="http://ejohn.org/blog/processingjs/">Processing.js</a></h1>
<h2>Inheritance</h2>
<p>A class can be defined using another class as a foundation. In object-oriented
programming terminology, one class can inherit fi elds and methods from another.
An object that inherits from another is called a subclass, and the object it
inherits from is called a superclass. A subclass extends the superclass.</p>
<p><a href="http://processing.org/learning/basics/inheritance.html"><b>Original Processing.org Example:</b> Inheritance</a><br>
<script type="application/processing">
SpinSpots spots;
SpinArm arm;
void setup()
{
size(200, 200);
smooth();
arm = new SpinArm(width/2, height/2, 0.01);
spots = new SpinSpots(width/2, height/2, -0.02, 33.0);
}
void draw()
{
background(204);
arm.update();
arm.display();
spots.update();
spots.display();
}
class Spin
{
float x, y, speed;
float angle = 0.0;
Spin(float xpos, float ypos, float s) {
x = xpos;
y = ypos;
speed = s;
}
void update() {
angle += speed;
}
}
class SpinArm extends Spin
{
SpinArm(float x, float y, float s) {
super(x, y, s);
}
void display() {
strokeWeight(1);
stroke(0);
pushMatrix();
translate(x, y);
angle += speed;
rotate(angle);
line(0, 0, 66, 0);
popMatrix();
}
}
class SpinSpots extends Spin
{
float dim;
SpinSpots(float x, float y, float s, float d) {
super(x, y, s);
dim = d;
}
void display() {
noStroke();
pushMatrix();
translate(x, y);
angle += speed;
rotate(angle);
ellipse(-dim/2, 0, dim, dim);
ellipse(dim/2, 0, dim, dim);
popMatrix();
}
}
</script><canvas width="200" height="200"></canvas></p>
<div style="overflow: hidden; height: 0px; width: 0px;"></div>
<pre><b>// All Examples Written by <a href="http://reas.com/">Casey Reas</a> and <a href="http://benfry.com/">Ben Fry</a>
// unless otherwise stated.</b>
SpinSpots spots;
SpinArm arm;
void setup()
{
size(200, 200);
smooth();
arm = new SpinArm(width/2, height/2, 0.01);
spots = new SpinSpots(width/2, height/2, -0.02, 33.0);
}
void draw()
{
background(204);
arm.update();
arm.display();
spots.update();
spots.display();
}
class Spin
{
float x, y, speed;
float angle = 0.0;
Spin(float xpos, float ypos, float s) {
x = xpos;
y = ypos;
speed = s;
}
void update() {
angle += speed;
}
}
class SpinArm extends Spin
{
SpinArm(float x, float y, float s) {
super(x, y, s);
}
void display() {
strokeWeight(1);
stroke(0);
pushMatrix();
translate(x, y);
angle += speed;
rotate(angle);
line(0, 0, 66, 0);
popMatrix();
}
}
class SpinSpots extends Spin
{
float dim;
SpinSpots(float x, float y, float s, float d) {
super(x, y, s);
dim = d;
}
void display() {
noStroke();
pushMatrix();
translate(x, y);
angle += speed;
rotate(angle);
ellipse(-dim/2, 0, dim, dim);
ellipse(dim/2, 0, dim, dim);
popMatrix();
}
}</pre>
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(C) Æliens
20/2/2008
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