p5.js | textWidth() Function

The textWidth() function is used to calculate the width of the text given as parameter. Syntax:

textWidth( theText )

Parameters: This function accepts a single parameter as mentioned above and described below:

• theText: It holds the string of which the width has to be measured.

Return Value: It returns a number which denotes the width of the given text. Below examples illustrate the textWidth() function in p5.js: Example 1:

javascript

let sampleChar = "P";
let sampleLine = "This is a sample text";

// Canvas area creating
function setup() {
  createCanvas(400, 200);
  textSize(20);
  text('The widths of the text are '
        + 'displayed below:', 20, 20);

  // Checking textwidth sampleChar
  text(sampleChar, 20, 80);
  let charWidth = textWidth(sampleChar);
  text("Width of the character is: "
        + charWidth, 20, 100);

  // Checking textwidth sampleLine
  text(sampleLine, 20, 140);
  let lineWidth = textWidth(sampleLine);
  text("Width of the line is: "
        + lineWidth, 20, 160);
}

Output: Example 2: Using text width measure to underline the text. 

javascript

let sampleText =
    "This is a sample sentence.";

// Canvas area creating
function setup() {
  createCanvas(400, 200);
  textSize(20);
  text('Click the button to underline'
        + ' the text below', 20, 40);
  text(sampleText, 20, 80);

  // Creating button
  btn = createButton("Underline text");
  btn.position(30, 120);
  btn.mousePressed(underlineText);
}

// Measuring text width and
// creating underline
function underlineText() {
  let width = textWidth(sampleText);
  line(20, 90, width + 20, 90);
}

Output: Online editor: https://editor.p5js.org/ Environment Setup: https://www.geeksforgeeks.org/p5-js-soundfile-object-installation-and-methods/ Reference: https://p5js.org/reference/#/p5/textWidth