Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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color rectBackground = color(0, 0, 255);
void setup(){
size(400, 400);
background(255);
rectMode(CENTER);
}
void draw(){
fill(rectBackground);
rect(width/2, height/2, 200, 200);
}
void keyPressed(){
if(key == CODED){
if (keyCode == UP) {
rectBackground = color(255, 0, 0);
}
else if (keyCode == DOWN) {
rectBackground = color(255, 255, 0);
}
else if (keyCode == RIGHT) {
rectBackground = color(0, 255, 0);
}
else {
rectBackground = color(255, 0, 255);
}
}
}
The keyCode property is used to check special keys on the keyboard, such as the arrow
keys. Processing defines these keys with constants (that’s why the arrow direction names
are in all caps). Before checking the individual key codes, you need to check if the key is
coded at all; this is handled by the external conditional if(key == CODED){}. For an up-todate
list of the available key codes in Processing, please refer to the online reference at
http://processing.org/reference/keyCode.html.
In addition to key codes, it’s also possible to detect the value of each standard key. The
next sketch is based on the last example, replacing the arrow keys with the keys A, S, W,
and Z, for left, right, up, and down, respectively.
color rectBackground = color(0, 0, 255);
void setup(){
size(400, 400);
background(255);
rectMode(CENTER);
}
void draw(){
fill(rectBackground);
rect(width/2, height/2, 200, 200);
}
void keyPressed(){
if(key == 'a'){