How to lock the vertical skewing of Ellipse using FabricJS?

FabricJSJavascriptHTML5 Canvas

In this tutorial, we are going to learn how to lock the vertical skewing of an Ellipse using FabricJS. Just as we can specify the position, color, opacity and dimension of an ellipse object in the canvas, we can also specify whether we want to stop skewing an object vertically. This can be done by using the lockSkewingY property.

Syntax

new fabric.Ellipse({ lockSkewingY : Boolean }: Object)

Parameters

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

Options Keys

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

Example 1

Default behaviour of an Ellipse object in the canvas

Let's see an example to understand the default behaviour of an Ellipse object when lockSkewingY 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>How to lock the vertical skewing of Ellipse using FabricJS?</h2>
      <p>Select the object and stretch it horizontally or vertically by pressing the <b>shift</b> key. The object will get skewed. This is the default behavior. Here we have not applied the <b>lockSkewing</b> property. </p>
      <canvas id="canvas"></canvas>

      <script>
         // Initiate a canvas instance
         var canvas = new fabric.Canvas("canvas");

         // Initiate an ellipse instance
         var ellipse = new fabric.Ellipse({
            left: 115,
            top: 50,
            fill: "white",
            rx: 80,
            ry: 50,
            stroke: "black",
            strokeWidth: 5,
         });

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

Example 2

Passing lockSkewingY as key with 'true' value

In this example, we will see how we can cease the ability of an ellipse object to skew vertically using the lockSkewingY property. Although we can skew the ellipse object horizontally, we are not allowed to perform the same action vertically.

<!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>How to lock the vertical skewing of Ellipse using FabricJS?</h2>
      <p>Select the object and stretch it horizontally by pressing the <b>shift</b> key. The object will get skewed. But we have locked its vertical skewing by applying the <b>lockSkewingY</b> property. </p>
      <canvas id="canvas"></canvas>

      <script>
         // Initiate a canvas instance
         var canvas = new fabric.Canvas("canvas");

         // Initiate an ellipse instance
         var ellipse = new fabric.Ellipse({
            left: 115,
            top: 50,
            fill: "white",
            rx: 80,
            ry: 50,
            stroke: "black",
            strokeWidth: 5,
            lockSkewingY: true,
         });

         // Adding it to the canvas
         canvas.add(ellipse);
         canvas.setWidth(document.body.scrollWidth);
         canvas.setHeight(250);
      </script>
   </body>
</html>
raja
Updated on 24-May-2022 13:52:05

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