p5.js noLoop() Function

The noLoop() function is used to stop the program after executing the draw() function. The loop() function runs the draw() function again and again. If noLoop() function is used in setup() function then it should be the last line inside the block. If noLoop() function is used then it is not possible to change or access the screen inside event handling functions such as mousePressed() or keyPressed().

Syntax:

noLoop()

Below examples illustrate the noLoop() function in p5.js:

Example 1:

function setup() {

  // Create canvas of given size
  createCanvas(500, 300);

  // Set the background color
  background('green');

  // Use noLoop() function
  noLoop();
}

function draw() {

  // Set the stroke color
  stroke('white');

  // Set the stroke width
  strokeWeight(4);

  // Function to draw the line
  line(50, 50, 450, 250);

}

Output:

Example 2:

let l = 0;

function setup() {

  // Create canvas of given size
  createCanvas(500, 300);

  // Set the background color
  background('green');

}

function draw() {

  // Set the stroke color
  stroke('white');

  l = l + 0.5;
  if (l > width) {
    l = 0;
  }

  // Function to draw the line
  line(l, 0, l, height);

}

function mousePressed() {
  noLoop();
}

function mouseReleased() {
  loop();
}

Output: