In this article, we are going to see how to enable the border scaling of the canvas 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, height, width, 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 enable the border scaling of the canvas triangle using borderScaleFactor property and render the polygon on the Canvas as given below.
Syntax:
fabric.Polygon([
{ x: pixel, y: pixel },
{ x: pixel, y: pixel },
{ x: pixel, y: pixel},
{ x: pixel, y: pixel},
{ x: pixel, y: pixel }],
{
borderScaleFactor: number
});
Parameter: This property accepts a single parameter as mentioned above and described below:
- borderScaleFactor: This parameter defines whether to enable or disable border scaling and how much.
Note: Dimension pixels is must create a polygon.
Below examples illustrate the Fabric.JS borderScaleFactor fill property in JavaScript:
Example 1: In this example, we will set the borderScaleFactor value 5.
HTML
<!DOCTYPE html> <html>   <head>     <!-- Loading the FabricJS library -->    <script src=     </script> </head>   <body>         <div style="text-align: center;width: 600px;">         <h1 style="color: green;">             neveropen         </h1>         <b>             Fabric.js | Polygon fill Property         </b>         </div>     <canvas id="canvas"            width="600"            height="200"            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 }], {             fill: 'purple',             borderScaleFactor: 5         });           // Render the polygon in canvas         canvas.add(polygon);     </script> </body>   </html> |
Output:
Example 2: In this example, we will set the borderScaleFactor value 1.
HTML
<!DOCTYPE html> <html>   <head>     <!-- Loading the FabricJS library -->    <script src=     </script> </head>   <body>         <div style="text-align: center;width: 600px;">         <h1 style="color: green;">             neveropen         </h1>         <b>             Fabric.js | Polygon borderScaleFactor Property         </b>         </div>     <canvas id="canvas"            width="600"            height="200"            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 }], {             fill: 'yellow',             borderScaleFactor: 1         });           // Render the polygon in canvas         canvas.add(polygon);     </script> </body>   </html> |
Output:
