Fabric.js is a javascript library that is used to work with canvas. Image is one of the class of fabric.js that is used to create image instances. The opacity property of the image is used to set the visibility of the image.
First import the fabric.js library. After importing the library, create a canvas block in the body tag which will contain the image. After this, initialize an instance of Canvas and image provided by FabricJS and set the opacity of the canvas image using the Opacity property of the image object.
Syntax:
fabric.Image(image, { opacity: 0.40 });
Parameters: The above function takes two parameters as mentioned above and described below:
- image: This parameter takes the image.
- opacity: This sets the opacity of the image.
Example 1: This example uses FabricJS to set the opacity of the canvas images as shown in the below given example.
<!DOCTYPE html> < html > < head > <!-- Adding the FabricJS library --> < script src = </ script > </ head > < body > < h1 style = "color: green;" >neveropen</ h1 > < b >Fabric.js | Image opacity Property </ b > < canvas id = "canvas" width = "400" height = "300" style = "border:2px solid #000000" > </ canvas > < img src = width = "50" height = "50" id = "my-image" > < script > // Create the instance of canvas object var canvas = new fabric.Canvas("canvas"); var img= document.getElementById('my-image'); var imgInstance = new fabric.Image(img, { opacity: 0.40 }); canvas.add(imgInstance); </ script > </ body > </ html > |
Output:
Example 2:
<!DOCTYPE html> < html > < head > <!-- Adding the FabricJS library --> < script src = </ script > </ head > < body > < h1 style = "color: green;" >neveropen</ h1 > < b >Fabric.js | Image opacity Property </ b > < canvas id = "canvas" width = "300" height = "200" style = "border:2px solid #000000" > </ canvas > < img src = width = "50" height = "50" id = "my-image" style = "display:none;" > < br > < button onclick = "func()" >Clickme</ button > < script > // Create the instance of canvas object var canvas = new fabric.Canvas("canvas"); var img= document.getElementById('my-image'); var imgInstance = new fabric.Image(img, { opacity: 1 }); let func=()=>{ var imgInstance = new fabric.Image(img, { opacity: 0.40 }); canvas.clear(); canvas.add(imgInstance); } canvas.add(imgInstance); </ script > </ body > </ html > |
Output: