How to create a canvas circle using Fabric.js ?

In this article, we are going to see how to create a canvas circle using FabricJS. The canvas means the circle is movable and can be stretched according to requirement. Further, the circle can be customized when it comes to initial stroke color, fill color, stroke width, or radius. 

Approach: To make it possible we are going to use a JavaScript library called FabricJS. After importing the library using CDN, we will create a canvas block in the body tag which will contain our circle. After this, we will initialize instances of Canvas and Circle provided by FabricJS and render the Circle on Canvas as given in the example below. 

Syntax:

fabric.Circle({
    radius: number,
    fill: string,
    stroke: string,
    strokeWidth: int
}); 

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

• radius: It specifies the radius of the circle.
• fill: It specifies the fill color.
• stroke: It specifies the stroke color.
• stroke-width: It specifies the width of the stroke.

Example: This example uses FabricJS to create a simple editable canvas circle. 

<script src=
"https://cdnjs.cloudflare.com/ajax/libs/fabric.js/3.6.2/fabric.min.js">
</script>

<canvas id="canvas" width="400" height="200" 
        style="border:2px solid #000000">
</canvas>

<script>
    // Initiate a Canvas instance
    var canvas = new fabric.Canvas("canvas");
    
    // Initiate a Circle instance
    var circle = new fabric.Circle({
        radius: 50,
        fill: '',
        stroke: 'green',
        strokeWidth: 3
    });
    
    // Render the circle in canvas
    canvas.add(circle);
</script>

Output: