Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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x+=speedX;
y+=speedY;
// Check display window edge collisions
if (x > width-w){
x = width-w;
speedX*=-1;
}
else if (x < 0){
x = 0;
speedX*=-1;
}
else if (y > height-h){
y = height-h;
speedY*=-1;
}
else if (y < 0){
y = 0;
speedY*=-1;
}
}
If you run the sketch, you should see a single rectangle bouncing off the four boundaries
of the display window. If it isn’t obvious, the key block of code that makes the rectangle
bounce off the walls is the following:
// Check display window edge collisions
if (x > width-w){
x = width-w;
speedX*=-1;
}
else if (x < 0){
x = 0;
speedX*=-1;
}
else if (y > height-h){
y = height-h;
speedY*=-1;
}
else if (y < 0){
y = 0;
speedY*=-1;
}
Each of the four if statements controls detection on one of the display window boundaries
(right, left, bottom, and top). Notice that the conditionals check if the rectangle is
either greater than (>) or less than (