Node.js GM drawPolyline() Function

Last Updated : 30 Mar, 2023

The drawPolyline() function is an inbuilt function in the GraphicsMagick library which is used to draw polylines with specified coordinates. The function returns the true value of success.

Syntax:

drawPolyline( [x0, y0], ..., [xn, yn] )

Parameters: This function accepts the array of x and y coordinates.

Return Value: This function returns the GraphicsMagick object.

Original Image:

Example 1:

javascript

// Include gm library
const gm = require('gm').subClass({imageMagick: true});
 
// Import the image
gm('1.png')
 
// Set the color for the stroke
.stroke("#000000")
 
// Invoke drawPolyline function with array of points
.drawPolyline([12, 60], [45, 79], [80, 120], [300, 32])
 
// Process and write the image
.write("drawPolyline1.png", function (err) {
    if (!err) console.log('done');
});

Output:

Example 2:

javascript

// Include gm library
const gm = require('gm');
 
// Import the image
gm(600, 300, 'white')
 
// set the color for the stroke
.stroke("green", 3)
 
// Set the font
.font("Helvetica.ttf", 60)
 
// Invoke drawPolyline function with
// array of points
.drawPolyline([12, 60], [45, 79], [80, 120],
        [300, 32], [400, 150], [500, 200])
 
// Call to drawText Function
.drawText(100, 280, "GeeksforGeeks!")
 
// Process and write the image
.write("drawPolyline1.png", function (err) {
    if (!err) console.log('done');
});