How to set the vertical scale factor of an Ellipse using FabricJS?

FabricJSJavascriptHTML5 Canvas

In this tutorial, we are going to learn how to set the vertical scale factor of an Ellipse using FabricJS. Ellipse is one of the various shapes provided by FabricJS. In order to create an ellipse, we have to create an instance of fabric.Ellipse class and add it to the canvas. Just as we can specify the position, color, opacity and dimension of an ellipse object in the canvas, we can also set the vertical scale of an ellipse object. This can be done by using the scaleY property.

Syntax

new fabric.Ellipse({ scaleY : Number }: 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 scaleY is a property.

Options Keys

  • scaleY − This property accepts a Number value. The value that is assigned, determines the vertical object scale factor. Its default value is 1.

Example 1

Default appearance when scaleY is not used

The following example shows how the ellipse would appear when the scaleY property is not used. By default, the vertical scale factor of the ellipse object is 1. scaleY determines the transformation that resizes an object along the Y-axis.

<!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>Setting the vertical scale factor of an Ellipse using FabricJS</h2>
      <p>Note that here we haven't set the vertical scale factor <b>scaleY</b> explicitly. By default, it is set to 1. </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,
            rx: 80,
            ry: 50,
            fill: "#ff1493",
         });

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

Example 2

Passing scaleY property as key

In this example, we are passing the scaleY property as a key with a value of 2. This means that the ellipse object's scale factor in the vertical direction is doubled.

<!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>Setting the vertical scale factor of an Ellipse using FabricJS</h2>
      <p>Here we have set <b>scaleY</b> to 2, so the vertical scale factor of the ellipse doubled. </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,
            rx: 80,
            ry: 50,
            fill: "#ff1493",
            scaleY: 2,
         });

         // Adding it to the canvas
         canvas.add(ellipse);
         canvas.setWidth(document.body.scrollWidth);
         canvas.setHeight(250);
      </script>
   </body>
</html>
raja
Updated on 25-May-2022 11:07:17

Advertisements