Images and animations are engaging, fun, and perfect for conveying information that is difficult to process and understand using written words alone. This is true for photos taken with a camera as well as drawings created using a computer. In this article, I will show you some of the best free and open source JavaScript drawing libraries.

There are many free libraries for drawing anything you want in the browser using technologies like the HTML5 canvas element and SVG. Not only can you draw using the APIs provided by these libraries, you can also animate anything you create.

let's start.

Two.js

Two.js is a very popular and easy-to-use library for drawing 2D shapes using JavaScript. It's well documented and you spend very little time learning the basics.

Two things you'll love about this library. First of all, it has nothing to do with rendering. This means you can use the same API to draw graphics on canvas elements via SVG or WebGL. This feature has saved me many times when I use this library. Secondly, the library also has built-in functionality to animate anything you draw on the screen.

You can also create simple games more easily by listening to different keyboard and mouse events to update the size, position, and color of different elements drawn on the screen.

The above example by Jono Brandel uses Two.js to create an animated wavy road on a canvas. You can find more interesting projects on the official website.

Paper.js

The Paper.js library is another free and open source solution for people who want to draw using JavaScript. The library uses canvas to handle its drawing animation. However, its main focus is on vector-based drawing rather than raster images.

There are two options available for you to create graphics using this library. You can continue to use regular JavaScript, or consider using a modified version of the library called PaperScript. Using PaperScript requires you to spend some extra time learning how to use it. However, it has some advantages, such as easier calculation of the Point and Size objects used throughout the library.

You can do a lot of interesting things with this library, including features like nested layers, simple paths, and compound paths. You can also smooth curves drawn using the library. You can also use blending modes to make the overlap between different elements more visually appealing.

Alberto Jerez’s CodePen above uses a bunch of these layers and compositing functions to create an interesting effect, with circles that change shape when collided.

P5.js

The p5.js library is a great choice for those who are looking for a library that does not have a steep learning curve but can create very complex systems if necessary. The P5.js entry page on the official website has a functional example. With just a few lines of code, a circle can be drawn wherever the mouse moves.

This library is inspired by the popular Java processing platform and has an active community that can help you when you get stuck. There are many examples available that demonstrate the capabilities of this library. They can be of great help when you are looking for inspiration. You can use them to learn how to simulate physics, create particle systems, and react to different user inputs.

The above example by Johan Karlsson uses p5.js to create some small insects that move randomly around the canvas. Clicking anywhere in the demo will create a new set of randomly placed mosquitoes.

Kangwa

The Konva library is a bit different than the libraries I've mentioned so far. You can use it to draw basic shapes on the canvas, but it's entirely possible to do much more. You can add high-performance animations and transitions to add visual appeal to anything you draw on the canvas.

What's special about this library is that it allows you to attach event handlers to anything you draw on the screen. You can select previously drawn objects on the canvas and move them around. You can also scale and rotate selected objects without affecting anything else you draw.

These features are great for those who want a library to help them create simple sketching applications and drag-and-drop games on the canvas. You can use groups to move and manipulate multiple shapes together.

The simple puzzle game above was built using Konva by Jakub Bene?. The basic idea is to choose a box with a slightly different color than the others.

Fabric.js

The Fabric.js library is built on the same philosophy as Konva and has many of the same features. In fact, Fabric.js actually seems to be more popular and active than Konva.

This library provides an interactive object model built on top of the canvas element. This basically means that you can draw different objects such as geometric shapes and images on the canvas to interact with them later. This library gives your users the option to move, scale, and rotate anything they draw on the canvas, allowing you to build simple mockup applications, meme generators, and more.

Try dragging text or adding your own shapes and images on the canvas of Martin Florian's CodePen above. The library's home page showcases more features, such as hand drawing and using patterns and gradients to fill shapes.

Snap.svg

The Snap.svg library is a popular choice for people who want to use the power of SVG and JavaScript to create resolution-independent vector graphics. The library is open source and completely free to use.

It comes with a clean and powerful API that can manipulate and animate any existing SVG content, as well as dynamically generate SVG content. The library was developed with support for IE9 and above in mind. This makes it easier for developers to provide features like masks, clipping, and patterns without worrying about support for older browsers.

Easy-to-use library provides many methods to create basic shapes and apply properties using key-value pairs, such as fill, Stroke, and StrokeWidth. You can also group elements together to make changes to multiple items at once. Different objects can be easily referenced by name or appropriate CSS selectors. Check out the example below written by Ronan Levesque.

SVG.js

If you want to draw and animate SVG using JavaScript, another popular option is to use the SVG.js library. The goal of the library developers is to make it as small and fast as possible while providing almost complete coverage of the SVG specification. There are no dependencies and the library can be used independently.

You can see its performance compared to Vanilla JS and Snap.svg on the site's homepage. You can create basic shapes and add them to the DOM using built-in functions. This library comes with various functions to manipulate the appearance of anything you draw on the screen. It also supports event listeners so that you can implement the ability to change or animate any SVG element based on user interaction.

Try changing the values ??of different options in George Francis' CodePen above to generate unique patterns using SVG.js.

JS Sequence Diagram

The last library on our list may not appeal to the masses, but it does serve a unique purpose and is worth mentioning. Have you ever been involved in a project where you had to draw a UML sequence diagram? If you agree, then the JS Sequence Gallery might be a great fit for you.

This library will quickly create a simple SVG-based sequence diagram for you using JavaScript. All you need to do is give it a valid textual representation. One thing you might not like is that this library depends on a bunch of other libraries to work properly. This includes Snap.svg, web font loader, underscore.js, and optionally jQuery.

However, this library is still a good choice for anyone who wants to quickly generate such charts without worrying about writing a lot of code. You can also apply your own CSS styles to change the color and fill of different components. Take a look at the E T demo above and try editing the code to see how the chart changes.

Final Thoughts

There are many free libraries available for drawing objects using JavaScript. My goal in this article is to highlight some popular libraries that have a nice feature set that solves unique problems. Hopefully this article helped you choose a library that can draw and animate elements on canvas as well as using SVG.

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