Web Front-end
JS Tutorial
How to set custom key to enable/disable unified scaling on FabricJS canvas?
How to set custom key to enable/disable unified scaling on FabricJS canvas?
In this article, we will learn how to set custom keys to enable/disable unified scaling in FabricJS. In FabricJS, when an object is dragged from a corner, the object transforms proportionally. This is called uniform scaling. However, we can enable/disable this behavior using uniScaleKey.
Syntax
new fabric.Canvas(element: HTMLElement|String, { uniScaleKey: String }: Object)Parameters
element - This parameter is the element itself, Document derivation can be used. getElementById() or the id of the element itself. The FabricJS canvas will be initialized on this element.
Options (optional) - This parameter is an object that provides additional customization to our canvas. Using this parameter, you can change many attributes related to the canvas, such as color, cursor, and border width, among which uniScaleKey is one attribute. It accepts a string value that determines which key toggles unified scaling. Its default value is shiftKey.
Example 1
Passing the uniScaleKey attribute with value "altKey"
Let's take a look at the customization for disabling unified scaling in FabricJS Code example for key. Here we set the uniScaleKey to "altKey".
<!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 a custom key to enable/disable uniform scaling on a canvas</h2>
<p>Hold the <b>alt</b> key and stretch the object diagonally. The object will scale non-uniformly. </p>
<canvas id="canvas"></canvas>
<script>
// Initiate a canvas instance
var canvas = new fabric.Canvas("canvas", {
uniformScaling: true,
uniScaleKey: "altKey"
});
// Creating an instance of the fabric.Rect class
var circle = new fabric.Circle({
left: 215,
top: 100,
radius: 50,
fill: "orange",
});
// Adding it to the canvas
canvas.add(circle);
canvas.setWidth(document.body.scrollWidth);
canvas.setHeight(250);
</script>
</body>
</html>Example 2
Pass the uniScaleKey attribute with the value "ctrlKey"
We can also pass "ctrlKey"' As the value of the uniScaleKey property, since it is also a modifier key. If a NULL value or a key that is not a modifier key is specified for uniScaleKey, its functionality will be disabled.
In this example, uniformScaling has been assigned a false value, which means the feature has been disabled. Once we press ctrlKey, uniform scaling will be enabled again.
<!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 a custom key to enable/disable uniform scaling on a canvas </h2>
<p>Hold the <b>ctrl</b> key and stretch the object diagonally. It will scale uniformly. </p>
<canvas id="canvas"></canvas>
<script>
// Initiate a canvas instance
var canvas = new fabric.Canvas("canvas", {
uniformScaling: false,
uniScaleKey: "ctrlKey"
});
// Creating an instance of the fabric.Rect class
var circle = new fabric.Circle({
left: 215,
top: 100,
radius: 50,
fill: "red",
});
// Adding it to the canvas
canvas.add(circle);
canvas.setWidth(document.body.scrollWidth);
canvas.setHeight(250);
</script>
</body>
</html>The above is the detailed content of How to set custom key to enable/disable unified scaling on FabricJS canvas?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1665
14
1424
52
1322
25
1269
29
1249
24
JavaScript Engines: Comparing Implementations
Apr 13, 2025 am 12:05 AM
Different JavaScript engines have different effects when parsing and executing JavaScript code, because the implementation principles and optimization strategies of each engine differ. 1. Lexical analysis: convert source code into lexical unit. 2. Grammar analysis: Generate an abstract syntax tree. 3. Optimization and compilation: Generate machine code through the JIT compiler. 4. Execute: Run the machine code. V8 engine optimizes through instant compilation and hidden class, SpiderMonkey uses a type inference system, resulting in different performance performance on the same code.
Python vs. JavaScript: The Learning Curve and Ease of Use
Apr 16, 2025 am 12:12 AM
Python is more suitable for beginners, with a smooth learning curve and concise syntax; JavaScript is suitable for front-end development, with a steep learning curve and flexible syntax. 1. Python syntax is intuitive and suitable for data science and back-end development. 2. JavaScript is flexible and widely used in front-end and server-side programming.
From C/C to JavaScript: How It All Works
Apr 14, 2025 am 12:05 AM
The shift from C/C to JavaScript requires adapting to dynamic typing, garbage collection and asynchronous programming. 1) C/C is a statically typed language that requires manual memory management, while JavaScript is dynamically typed and garbage collection is automatically processed. 2) C/C needs to be compiled into machine code, while JavaScript is an interpreted language. 3) JavaScript introduces concepts such as closures, prototype chains and Promise, which enhances flexibility and asynchronous programming capabilities.
JavaScript and the Web: Core Functionality and Use Cases
Apr 18, 2025 am 12:19 AM
The main uses of JavaScript in web development include client interaction, form verification and asynchronous communication. 1) Dynamic content update and user interaction through DOM operations; 2) Client verification is carried out before the user submits data to improve the user experience; 3) Refreshless communication with the server is achieved through AJAX technology.
JavaScript in Action: Real-World Examples and Projects
Apr 19, 2025 am 12:13 AM
JavaScript's application in the real world includes front-end and back-end development. 1) Display front-end applications by building a TODO list application, involving DOM operations and event processing. 2) Build RESTfulAPI through Node.js and Express to demonstrate back-end applications.
Understanding the JavaScript Engine: Implementation Details
Apr 17, 2025 am 12:05 AM
Understanding how JavaScript engine works internally is important to developers because it helps write more efficient code and understand performance bottlenecks and optimization strategies. 1) The engine's workflow includes three stages: parsing, compiling and execution; 2) During the execution process, the engine will perform dynamic optimization, such as inline cache and hidden classes; 3) Best practices include avoiding global variables, optimizing loops, using const and lets, and avoiding excessive use of closures.
Python vs. JavaScript: Community, Libraries, and Resources
Apr 15, 2025 am 12:16 AM
Python and JavaScript have their own advantages and disadvantages in terms of community, libraries and resources. 1) The Python community is friendly and suitable for beginners, but the front-end development resources are not as rich as JavaScript. 2) Python is powerful in data science and machine learning libraries, while JavaScript is better in front-end development libraries and frameworks. 3) Both have rich learning resources, but Python is suitable for starting with official documents, while JavaScript is better with MDNWebDocs. The choice should be based on project needs and personal interests.
Python vs. JavaScript: Development Environments and Tools
Apr 26, 2025 am 12:09 AM
Both Python and JavaScript's choices in development environments are important. 1) Python's development environment includes PyCharm, JupyterNotebook and Anaconda, which are suitable for data science and rapid prototyping. 2) The development environment of JavaScript includes Node.js, VSCode and Webpack, which are suitable for front-end and back-end development. Choosing the right tools according to project needs can improve development efficiency and project success rate.
