Home > Article > Web Front-end > How to set the minimum scale value allowed for a Circle using FabricJS?
In this tutorial, we will learn how to set the minimum allowed ratio of a Circle using FabricJS. Circles are one of the various shapes provided by FabricJS. In order to create a circle, we must create an instance of the Fabric.Circle class and add it to the canvas. We can customize the circular object by adding a fill color, removing its borders, and even changing its dimensions. Likewise, we can also use the minScaleLimit property to set its minimum allowed scale.
new fabric.Circle({ minScaleLimit : Number }: Object)
Options (optional) - This parameter is a Object Provides additional customization for our circles. Using this parameter, you can change the color, cursor, border width, and many other properties associated with the object for which minScaleLimit is a property.
##minScaleLimit - This property accepts numbers strong> As a value that allows us to control the minimum allowed proportion of the circle.
Appearance of the default circle object
Let's take a look at the code to see what happens when # is not used ##minScaleLimit property, what the circular object looks like. In this case we will be able to scale the object freely since no minimum limit is set. <!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 minimum allowed scale value of circle using FabricJS</h2>
<p>Select the object and scale it down by dragging one of its controlling corners. Here you can scale down the object freely since there is no minimum limit set.</p>
<canvas id="canvas"></canvas>
<script>
// Initiate a canvas instance
var canvas = new fabric.Canvas("canvas");
var circle = new fabric.Circle({
left: 115,
top: 50,
radius: 50,
fill: "#ff1493"
});
// Adding it to the canvas
canvas.add(circle);
canvas.setWidth(document.body.scrollWidth);
canvas.setHeight(250);
</script>
</body>
</html>
Example 2
minScaleLimit attribute as a key with a custom value In this example, We'll see how assigning a value to the
minScaleLimit property changes the minimum allowed scale value for a circular object in the canvas. Here we are using 0.8 as the value, which means that we will not be able to shrink the object to a radius smaller than 64 pixels, which is calculated by radius * limit (0.8 * 80 = 64 pixels). <!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 minimum allowed scale value of circle using FabricJS</h2>
<p>Select the object and try to scale it down by dragging one of its controlling corners. You cannot scale down the object freely, as we have set <b>minScaleLimit</b> at 0.8. So, the minimum scale of the circle must be at least 80% of the original radius, beyond which you cannot scale it down any further. </p>
<canvas id="canvas"></canvas>
<script>
// Initiate a canvas instance
var canvas = new fabric.Canvas("canvas");
var circle = new fabric.Circle({
left: 115,
top: 50,
radius: 80,
fill: "#ff1493",
minScaleLimit: 0.8
});
// Adding it to the canvas
canvas.add(circle);
canvas.setWidth(document.body.scrollWidth);
canvas.setHeight(250);
</script>
</body>
</html>
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