Fabric.js Polygon cornerStrokeColor Property

Last Updated : 31 Aug, 2020

In this article, we are going to see how to set the color of controlling corners of the canvas of polygon using FabricJS. The canvas polygon means the polygon is movable and can be stretched according to requirement. Further, the polygon can be customized when it comes to initial stroke color, shape, 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 polygon. After this, we will initialize instances of Canvas and polygon provided by FabricJS and set the color of controlling corners of the canvas polygon using cornerStrokeColor property and render the polygon on the Canvas as given in the below example.

Syntax:

fabric.Polygon([
      { x: pixel, y: pixel },
      { x: pixel, y: pixel },
      { x: pixel, y: pixel },
      { x: pixel, y: pixel },
      { x: pixel, y: pixel }],
      {
                   cornerStrokeColor: string
      }
)

Parameters: This property accepts a single parameter as mentioned above and described below:

cornerStrokeColor: It is a string that specifies the color that would be used for the controlling corners.

Note: The dimension pixels are a must for creating a polygon.

Below example illustrate the Polygon cornerStrokeColor Property in JavaScript:

Example:

HTML

<!DOCTYPE html> 
<html> 
<head> 
  <!-- Loading 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 | Polygon cornerStrokeColor Property 
    </b> 
  </div> 
  <canvas id="canvas" width="600" height="300" 
          style="border:1px solid #000000;"> 
  </canvas> 
  <script> 
  
    // Initiate a Canvas instance  
    var canvas = new fabric.Canvas("canvas"); 
  
    // Initiate a polygon instance  
    var polygon = new fabric.Polygon([ 
      { x: 295, y: 10 }, 
      { x: 235, y: 198 }, 
      { x: 385, y: 78 }, 
      { x: 205, y: 78 }, 
      { x: 355, y: 198 }], { 
      transparentCorners: false, 
        
      // Set the corner stroke 
      // color to red 
      cornerStrokeColor: 'red' 
    }); 
  
    // Render the polygon in canvas  
    canvas.add(polygon);  
  </script> 
</body> 
</html>