Fabric.js Polyline lockMovementX Property

Last Updated : 22 Jan, 2021

In this article, we are going to see how to lock the vertical movement of the canvas Polyline using FabricJS. The canvas Polyline means the Polyline is movable and can be stretched according to requirement. Further, the Polyline can be customized when it comes to initial stroke color, height, width, fill color, or stroke width.

To make it possible we are going to use a JavaScript library called FabricJS. After importing the library, we will create a canvas block in the body tag that will contain the Polyline. After this, we will initialize instances of Canvas and Polyline provided by FabricJS and lock the horizontal movement of the canvas Polyline using lockMovementX property and render the Polyline on the Canvas as given in the below example.

Syntax:

var polyline = new fabric.Polyline(Points, {  
        lockMovementX: Boolean
     });

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

lockMovementX: It is a boolean value that specifies whether to lock the horizontal movement of canvas or not.

The below example illustrates the lockMovementX property in Fabric.js:

Example:

HTML

<!DOCTYPE html>  
<html>  
<head>  
  
    <!-- Loading the FabricJS library -->
    <script src=  
"https://cdnjs.cloudflare.com/ajax/libs/fabric.js/3.6.2/fabric.min.js">  
    </script>  
</head>  
  
<body>  
        <div style="text-align: center;width: 600px;">  
        <h1 style="color: green;">  
            GeeksforGeeks  
        </h1>  
        <b>  
            Fabric.js | Polyline lockMovementX Property  
        </b>  
        </div>  
    <canvas id="canvas"
            width="600"
            height="200"
            style="border:1px solid #000000;">  
    </canvas>  
  
    <script>  
  
        // Initiate a Canvas instance  
        var canvas = new fabric.Canvas("canvas");  
  
        // Initiate a polyline instance  
        var polyline = new fabric.Polyline([  
        { x: 200,  
            y: 10 },  
        {x: 250,  
            y: 50  
        }, {  
            x: 250,  
            y: 180  
        }, {  
            x: 150,  
            y: 180  
        }, {  
            x: 150,  
            y: 50  
        }, {  
            x: 200,  
            y: 10 }], {  
            stroke: 'green',   
            strokeWidth: 3,   
            cornerStyle: 'circle',   
            // Disable movement  
            // along the x-axis  
            lockMovementX: true  
  
        });  
  
        // Render the polyline in canvas  
        canvas.add(polyline);  
    </script>  
</body>  
  
</html>