Random pathways with controls.

​

- mouseX controls range (speed) of motion

- mouseY controls interval (how often there is a random change in direction)

​

When mouse is pressed:

- mouse position relative to center controls direction and extent of drift

When key is pressed:

- mouseY controls yscl (verticality)

​

*/

​

// Store x,y coordinates of current location

let x, y;

// Store x,y coordinates of previous location

let px, py;

// Store current xspeed and yspeed

let xspeed, yspeed;

​

// # of frames to wait before changing direction.

let interval;

// Range of random, relative range of vertical random

let range, yscl;

// How much to shift right/left, up/down

let xshift, yshift;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  x = width / 2;

  y = (height / 2) + 120;

  px = x;

  py = y;

​

  xspeed = 0;

  yspeed = 0;

​

  interval = 1;

  range = 1;

  yscl = 1;

  xshift = 1;

  yshift = 1;

​

  background(0);

  noStroke();

}

​

function draw() {

​

  // Draw very transparent background every frame

  // to create fade-out effect

  background(0, 5);

​

  //Change direction

  if (frameCount % interval == 1) {

    xspeed = random(-range, range * xshift); //shift median to go right/left

    yspeed = random(-range, range * yshift)*yscl; // shift median to go up/down

  }

​

  // Move

  x += xspeed;

  y += yspeed;

​

  // Draw a line from the previous loc to this loc

  stroke(255);

  strokeWeight(10);

  line(px, py, x, y);

​

  // Remember current location for next frame

  px = x;

  py = y;

​

  // Wrap around screen

  if (x < 0 || x > width || y < 0 || y > height) {

    if (x < 0) x = width;

    else if (x > width) x = 0;

    if (y < 0) y = height;

    else if (y > height) y = 0;

​

    // Don't draw line when wrapping around

    px = x;

    py = y;

  }

​

  // Draw a landmark in the center

  fill(255);

  noStroke();

  rect(width / 2, height / 2, 10, 10);

​

  // Controls

  if (keyIsPressed) {

    // mouseY controls yscl (verticality)

    yscl = mouseY / (height/2);

  }

  // Mouse position relative to center sets directional drift

  else if (mouseIsPressed) {

    // Horizontal shift

    xshift = mouseX / (width / 2);

    // Vertical shift

    yshift = mouseY / (height / 2);

  }

  else {

    // mouseX controls range (speed)

    range = 100 * mouseX / width;

    // mouseY controls interval (frequency of change)

    interval = int(1200*mouseY/height);

  }

}