p5.js setup() Function

The setup() function runs when the program starts. It is used to set the initial environment properties such as text-color, screen size, background-color and load the media file such as images and fonts. The program contains only one setup() function. The setup() function can not be called again after its initial execution.

Note: The variable declaration within setup() function can not be access by other functions including draw() function.

Syntax:

setup()

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

Example 1:

function setup() {

    // Create Canvas of given size
    createCanvas(400, 300);

}

function draw() {

    background(220);

    // Use color() function
    let c = color('green');

    // Use fill() function to fill color
    fill(c);

    // Draw a rectangle
    rect(50, 50, 300, 200);

}

Output:

Example 2:

function setup() {

    // Create Canvas of given size
    var cvs = createCanvas(600, 250);
}

function draw() {

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

    // Use createDiv() function to
    // create a div element
    var myDiv = createDiv('GeeksforGeeks');

    var myDiv1 = createDiv('A computer science portal for geeks');

    // Use child() function
    myDiv.child(myDiv1);

    // Set the position of div element
    myDiv.position(150, 100);

    myDiv.style('text-align', 'center');

    // Set the font-size of text
    myDiv.style('font-size', '24px');

    // Set the font color
    myDiv.style('color', 'white');

}

Output: