Fabric.js | Triangle centeredScaling Property

Last Updated : 02 Feb, 2021

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

To make this 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 which will contain the triangle. After this, we will initialize instances of Canvas and triangle provided by FabricJS and enable the centered scaling of the canvas triangle using centeredscaling property and render the triangle on the Canvas as given below.

Syntax:

fabric.Triangle({
    width: number,
    height: number,
    centeredscaling: boolean
});

Parameters: This function accepts three parameters as mentioned above and described below:

width: It specifies the width of triangle.
height: It specifies the height of triangle.
centeredScaling: This parameter defines whether to enable or disable centered scaling.

Example: This example uses FabricJS to enable the centered scaling of the canvas-like triangle as given below. Try scaling the object after enabling centered scaling, it will scale from all sides when you will scale it.

HTML

<!DOCTYPE html> 
<html> 
 
<head> 
    <title> 
        Fabric.js | Triangle centeredScaling Property 
    </title> 
     
    <!-- Adding 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 | Triangle centeredScaling 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 triangle instance 
        var triangle = new fabric.Triangle({
                        width: 150, 
                        height: 100, 
                        fill: '', 
                        stroke: 'green', 
                        strokeWidth: 3, 
                        cornerColor: 'blue', 
                        centeredScaling: true
        });
 
        // Render the triangle in canvas 
        canvas.add(triangle); 
        canvas.centerObject(triangle); 
    </script> 
</body> 
 
</html> 