Examples+
Bounce
When the shape hits the edge of the window, it reverses its direction.
Highlighted Features
/**
* Bounce.
*
* When the shape hits the edge of the window, it reverses its direction.
*/
int rad = 60; // Width of the shape
float xpos, ypos; // Starting position of shape
float xspeed = 2.8; // Speed of the shape
float yspeed = 2.2; // Speed of the shape
int xdirection = 1; // Left or Right
int ydirection = 1; // Top to Bottom
void setup()
{
size(640, 360);
noStroke();
frameRate(30);
ellipseMode(RADIUS);
// Set the starting position of the shape
xpos = width/2;
ypos = height/2;
}
void draw()
{
background(102);
// Update the position of the shape
xpos = xpos + ( xspeed * xdirection );
ypos = ypos + ( yspeed * ydirection );
// Test to see if the shape exceeds the boundaries of the screen
// If it does, reverse its direction by multiplying by -1
if (xpos > width-rad || xpos < rad) {
xdirection *= -1;
}
if (ypos > height-rad || ypos < rad) {
ydirection *= -1;
}
// Draw the shape
ellipse(xpos, ypos, rad, rad);
}
This example is for Processing 4+. If you have a previous version, use the examples included with your software. If you see any errors or have suggestions, please let us know.