Fabric.js Polyline perPixelTargetFind Property

Last Updated : 22 Jan, 2021

In this article, we are going to see the perPixelTargetFind property of a Polyline canvas using FabricJS. The canvas polyline is movable and can be stretched according to requirements. 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 set the perPixelTargetFind of canvas polyline using perPixelTargetFind property, and render the polyline on the canvas as given in the below example.

Syntax:

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

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

perPixelTargetFind: When set to true, objects are found on canvas on a per-pixel basis rather according to the bounding box.

The below example illustrates the left 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 perPixelTargetFind 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',   
            perPixelTargetFind: true   
  
  
        });  
  
        // Render the polyline in canvas  
        canvas.add(polyline);  
    </script>  
</body>  
  
</html>