Bouncing Ball
/**
* Bouncing Ball with Vectors
* by Daniel Shiffman.
*
* Demonstration of using vectors to control motion
* of a body. This example is not object-oriented
* See AccelerationWithVectors for an example of how
* to simulate motion using vectors in an object.
*/
PVector location; // Location of shape
PVector velocity; // Velocity of shape
PVector gravity; // Gravity acts at the shape's acceleration
void setup() {
size(640, 360);
location = PVector(100, 100);
velocity = PVector(1.5, 2.1);
gravity = PVector(0, 0.2);
}
void draw() {
background(0);
// Add velocity to the location.
location.add(velocity);
// Add gravity to velocity
velocity.add(gravity);
// Bounce off edges
if ((location.x > width) || (location.x < 0)) {
velocity.x = velocity.x * -1;
}
if (location.y > height) {
// We're reducing velocity ever so slightly
// when it hits the bottom of the window
velocity.y = velocity.y * -0.95;
location.y = height;
}
// Display circle at location vector
stroke(255);
strokeWeight(2);
fill(127);
ellipse(location.x, location.y, 48, 48);
}