How to lock the horizontal skewing of Circle using FabricJS?

FabricJSJavascriptHTML5 Canvas

In this tutorial, we are going to learn how to lock the horizontal skewing of a Circle using FabricJS. Just as we can specify the position, colour, opacity and dimension of a circle object in the canvas, we can also specify whether we want to stop skewing an object horizontally. This can be done by using the lockSkewingX property.

Syntax

new fabric.Circle({ lockSkewingX : Boolean }: Object)

Parameters

  • options (optional) − This parameter is an Object which provides additional customizations to our circle. Using this parameter, properties such as colour, cursor, stroke width and a lot of other properties can be changed related to the object of which lockSkewingX is a property.

Options Keys

  • lockSkewingX − This property accepts a Boolean value. If we assign it a 'true' value, then the object's horizontal skewing will be locked.

Example 1

Default behaviour of a Circle object in the canvas

Let's see a code to understand the default behaviour of a Circle object when lockSkewingX property is not used. Skewing the object in both horizontal and vertical directions is feasible by pressing the shift key and then dragging along the horizontal or vertical direction.

<!DOCTYPE html>
<html>
   <head>
      <!-- Adding the Fabric JS Library-->
      <script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/510/fabric.min.js"></script>
   </head>

   <body>
      <h2>Locking the horizontal skewing of circle using FabricJS</h2>
      <p>Select the object, hold the <b>shift</b> key, and stretch the object horizontally or vertically. You will notice that the object gets skewed freely in either direction. This is the default behavior. Here we have not applied the <b>lockSkewingX</b> property, but by default, it is set to False. </p>
      <canvas id="canvas"></canvas>

      <script>
         // Initiate a canvas instance
         var canvas = new fabric.Canvas("canvas");
         var circle = new fabric.Circle({
            left: 115,
            top: 50,
            fill: "white",
            radius: 50,
            stroke: "black",
            strokeWidth: 5
         });

         // Adding it to the canvas
         canvas.add(circle);
         canvas.setWidth(document.body.scrollWidth);
         canvas.setHeight(250);
      </script>
   </body>
</html>

Example 2

Passing lockSkewingX as key with 'true' value

In this example we will see how we can cease the ability of a circle object skew horizontally using the lockSkewingX property. As we can see, although we can skew the circle object vertically by pressing the Shift key, we are not allowed to perform the same action horizontally.

<!DOCTYPE html>
<html>
   <head>
      <!-- Adding the Fabric JS Library-->
      <script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/510/fabric.min.js"></script>
   </head>

   <body>
      <h2>Locking the horizontal skewing of a circle using FabricJS</h2>
      <p>Select the object, hold the <b>shift</b> key, and try to stretch the object horizontally. You will notice that horizontal skewing is not allowed, as we have set <b>lockSkewingX</b> to True. You can however skew the object in the vertical direction.</p>
      <canvas id="canvas"></canvas>

      <script>
         // Initiate a canvas instance
         var canvas = new fabric.Canvas("canvas");
         var circle = new fabric.Circle({
            left: 115,
            top: 50,
            fill: "white",
            radius: 50,
            stroke: "black",
            strokeWidth: 5,
            lockSkewingX: true
         });

         // Adding it to the canvas
         canvas.add(circle);
         canvas.setWidth(document.body.scrollWidth);
         canvas.setHeight(250);
      </script>
   </body>
</html>
raja
Updated on 25-May-2022 11:46:40

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