Linear motion.

*/

​

// Variables to store x,y coordinates

let x, y;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

​

  // Initial position is middle, near the top

  x = width / 2;

  y = 10;

  // Don't draw an outline

  noStroke();

}

​

function draw() {

  // Draw black background

  background(0);

​

  //Move horizontally to the left .4 pixels every frame

  x = x + -0.4;

  // Move vertically down .8 pixels every frame

  y = y + 0.8;

​

  // Set fill color to white

  fill(255);

  // Draw a circle at x,y

  ellipse(x, y, 10, 10);

}