Javascript

Introduction to Babylon.js

Published Mar 6, 2024

Updated Mar 6, 2024

7 min read

Babylon.js is a powerful, open-source 3D engine capable of rendering interactive 3D and 2D graphics using JavaScript. It is a great choice for creating games, demos, visualizations, and other 3D applications for the web or even for VR.

Being free, open-source, and cross-platform, Babylon.js is a great alternative to proprietary 3D engines like Unity and Unreal Engine. It is also a great alternative to other open-source 3D engines like Three.js and PlayCanvas as it provides TypeScript types out of the box, is optimized for performance, and provides advanced debugging tools. Its developer experience is excellent, and it has a large and active community making it a great choice for creating 3D applications for the web for both beginners and experts alike.

Getting Started

Babylon.js supports both ES6 and CommonJS module imports:

CommonJS Babylon.js npm packages support CommonJS/ES6 imports, UMD, and AMD-imports.
For developers seeking optimization through tree shaking, Babylon.js offers ES6 packages. These include @babylonjs/core for the core functionalities, and additional modules like @babylonjs/materials, @babylonjs/loaders, @babylonjs/gui, etc. It's important not to mix ES6 and legacy packages.

If you want to use the CommonJS module imports, you can install Babylon.js as follows:

npm install --save babylonjs

Then, include it in your JavaScript or TypeScript file:

import * as BABYLON from "babylonjs";

If you want to use the ES6 module imports, you can install Babylon.js as follows:

npm install --save @babylonjs/core

Then, include it in your JavaScript or TypeScript file:

import { Engine, Scene } from "@babylonjs/core";

I prefer the ES6 module imports because they allow for tree shaking, which can significantly reduce the size of the final bundle. However, in this tutorial, I will be using the CommonJS module imports because that's what the Babylon.js playground uses.

Creating Your First Babylon.js Scene

The Babylon.js Playground is an essential tool for learning and developing with Babylon.js. It's a user-friendly environment where you can write code and immediately see the results in a live scene. The playground comes with a default scene, and experimenting with it is a great way to start.

Apart from playing around with the default scene, you can also search the playground if you want to see examples of specific features. For example, if you search for "physics," you will find several examples of physics in action.

The playground is also often used to share code snippets on the Babylon.js forum both when asking for help and when helping others. I often found myself googling specific Babylon.js problems or features and finding a playground example that helped me understand and solve my problem.

Creating and Modifying Meshes

Meshes are fundamental in 3D graphics. In Babylon.js, creating a basic mesh, like a sphere, involves a few lines of code:

var sphere = BABYLON.MeshBuilder.CreateSphere(
  "sphere",
  { diameter: 2, segments: 32 },
  scene
);
sphere.position.y = 1;

You can also create materials and assign them to meshes to change their appearance. For example, to make a ground plane red, you would write:

const groundMaterial = new BABYLON.StandardMaterial("Ground Material", scene);
groundMaterial.diffuseColor = BABYLON.Color3.Red();
ground.material = groundMaterial;

Textures can also be added to materials:

var groundTexture = new BABYLON.Texture(
  Assets.textures.checkerboard_basecolor_png.rootUrl,
  scene
);
groundMaterial.diffuseTexture = groundTexture;

Importing and Using Meshes

Babylon.js allows for the importation of complex meshes, which can be scaled and positioned within the scene:

BABYLON.SceneLoader.ImportMesh(
  "",
  Assets.meshes.MyCustomMesh.rootUrl,
  Assets.meshes.MyCustomMesh.filename,
  scene,
  function (newMeshes) {
    newMeshes[0].scaling = new BABYLON.Vector3(0.1, 0.1, 0.1);
  }
);

Making the Scene Interactive

Interactivity is a key aspect of web experiences. Attaching controls to a camera enables user interaction through click-and-drag operations.

var camera = new BABYLON.ArcRotateCamera(
  "Camera",
  0,
  0,
  10,
  BABYLON.Vector3.Zero(),
  scene
);
camera.attachControl(canvas, true);

Adding Virtual Reality Support

Virtual reality is an exciting new technology that allows users to experience 3D environments more immersively. Babylon.js has built-in support for virtual reality, which can be enabled with a few lines of code:

const experience = await scene.createDefaultXRExperienceAsync();
const camera = experience.baseExperience.camera;
camera.attachControl(true);

You just create an XR experience, get the camera from the base experience, and attach it to the canvas and you should be all set for VR. If you don't own a VR headset, you can still test your scene in VR using the Immersive Web Emulator Chrome Extension.

Adding Physics

Physics is an important part of many 3D applications. Babylon.js has a built-in physics engine that can be enabled with a few lines of code:

var gravityVector = new BABYLON.Vector3(0, -9.81, 0);
var physicsPlugin = new BABYLON.CannonJSPlugin();
scene.enablePhysics(gravityVector, physicsPlugin);

Physics can be applied to meshes by setting their physicsImpostor property:

sphere.physicsImpostor = new BABYLON.PhysicsImpostor(
  sphere,
  BABYLON.PhysicsImpostor.SphereImpostor,
  { mass: 1, restitution: 0.9 },
  scene
);

Adding Lights

Lights are essential for creating realistic scenes. In Babylon.js, there are four main types of lights, each offering unique properties and effects:

Directional Light: Mimics sunlight, emitting parallel light rays across the entire scene. It's defined by a direction vector and has an infinite range.
Point Light: Resembles a light bulb, radiating light equally in all directions from a single point in space.
Spot Light: Functions like a flashlight, emitting a conical beam of light from a specific position in a given direction. Its illumination area and decay are controlled by angle and exponent parameters.
Hemispheric Light: Simulates ambient environment lighting, defined by a direction, usually upwards. Its effect is influenced by setting different color properties.

Each light type can be customized using properties like intensity and range, and you can control which meshes they illuminate. For more complex lighting scenarios, lightmaps can be utilized to pre-calculate and store lighting effects.

For example, to add a directional light to the scene, you could write:

var light = new BABYLON.DirectionalLight(
  "DirectionalLight",
  new BABYLON.Vector3(0, -1, 0),
  scene
);

Adding Shadows

Shadows are an important part of creating realistic scenes as they can help convey the 3D structure of the scene by providing cues about the relative positions and distances of objects, enhancing the perception of depth and dimension. Babylon.js has several types of shadows, including PCF, PCFSoft, and PCSS. For example, to add PCF shadows to the scene, you would write:

var shadowGenerator = new BABYLON.ShadowGenerator(1024, light);
shadowGenerator.usePoissonSampling = true;
shadowGenerator.bias = 0.0001;
shadowGenerator.normalBias = 0.01;
shadowGenerator.setDarkness(0.5);
shadowGenerator.useBlurExponentialShadowMap = true;
shadowGenerator.blurKernel = 32;
shadowGenerator.blurScale = 2;
shadowGenerator.blurBoxOffset = 1;
shadowGenerator.useKernelBlur = true;

shadowGenerator.addShadowCaster(sphere);

Adding Audio

Audio is an important part of many 3D applications. Babylon.js has a built-in audio engine that can be enabled with a few lines of code:

var audioEngine = new BABYLON.AudioEngine();

Audio can be added to the scene by creating a sound object:

var sound = new BABYLON.Sound(
  "Sound",
  `${Assets.sound.cannonBlast.rootUrl}${Assets.sound.cannonBlast.filename}`,
  scene,
  null,
  { loop: true, autoplay: true }
);

This particular example would play a "cannon blast" sound on a loop in your scene. The cannon blast asset is preloaded in the Babylon.js playground. If you were to load a custom asset in your application, you would simply provide a URL pointing to the sound file on the filesystem. For more details, you can check the documentation on playing sounds in Babylon.js.

Adding User Interface Elements

User interface elements can be used to add interactivity to a scene. Babylon.js provides a GUI library extension built on top of the DynamicTexture. For example, to add a dialog to the scene containing a button, you would write:

var guiManager = new BABYLON.GUI.GUI3DManager(scene);

const slate = new BABYLON.GUI.HolographicSlate("down");
slate.minDimensions = new BABYLON.Vector2(5, 5);
slate.dimensions = new BABYLON.Vector2(5, 5);
slate.titleBarHeight = 0.75;
slate.title = "Button!";
guiManager.addControl(slate);

var button = BABYLON.GUI.Button.CreateSimpleButton("button", "Click me!");
button.width = 0.5;
button.height = 0.25;
button.background = "green";
button.textBlock.color = "white";
button.onPointerClickObservable.add(() => {
  alert("Hi!");
});

slate.content = button;
slate.position = new BABYLON.Vector3(-2, 2, 0);

To use the ES6 version, you'll need to install the @babylonjs/gui package:

npm install --save @babylonjs/gui

Then, import it into your JavaScript or TypeScript file like this:

import { GUI3DManager, HolographicSlate, Button } from "@babylonjs/gui";

Tip: In case you don't like the controls that allow users to tilt the HolographicSlate, you can disable them by setting slate._gizmo._rootMesh.setEnabled(false); after adding the slate to your scene.

Adding Animations

Animations can be used to add movement to a scene. Babylon.js has several types of animations, including keyframe, bone, and morph target. For example, to add a keyframe animation to the scene, you would write:

var animationBox = new BABYLON.Animation(
  "myAnimation",
  "scaling.x",
  30,
  BABYLON.Animation.ANIMATIONTYPE_FLOAT,
  BABYLON.Animation.ANIMATIONLOOPMODE_CYCLE
);
var keys = [];
keys.push({
  frame: 0,
  value: 1,
});
keys.push({
  frame: 20,
  value: 0.2,
});
keys.push({
  frame: 100,
  value: 1,
});
animationBox.setKeys(keys);
sphere.animations.push(animationBox);
scene.beginAnimation(sphere, 0, 100, true);

Here's an explanation of what the code does:

Animation Creation: A BABYLON.Animation object named "myAnimation" is created to animate the scaling.x property, indicating the animation will affect the object's width. It runs at 30 frames per second, with values represented as floats, and loops continuously.
Defining Keyframes: Three keyframes are defined:
- At frame 0, the scale is 1 (original size).
- At frame 20, the scale reduces to 0.2.
- At frame 100, the scale returns to 1.
Applying and Starting Animation: The animation is assigned to the sphere object and starts immediately, looping between frames 0 and 100. This creates a pulsating effect on the sphere's width.

For a deeper dive into animations, you can check out the Babylon.js Animation Documentation.

Debugging

Debugging is an important part of any development process. Babylon.js has a built-in debug layer that can be enabled with a few lines of code:

scene.debugLayer.show();

The debug layer provides a user-friendly interface for inspecting and modifying the scene. It can also show you the current frame rate and other performance metrics and lets you export the performance data.

In case you are using the ES6 module imports, you'll need to install the @babylonjs/inspector package:

npm install --save @babylonjs/inspector

Then, import it into your JavaScript or TypeScript file like this:

import "@babylonjs/inspector";

Once you're satisfied with your creation, you can download it as an HTML file and host it on platforms like GitHub Pages, making it accessible to the world.

You can also share your scene with others by sharing the playground URL. For example, the URL for the default scene is https://playground.babylonjs.com/#6QY4X1#1.

In case you would like to integrate your scene with a framework of your choice, you can check out the Babylon.js External Libraries Documentation where you can find examples of Babylon.js being used with frameworks like React, Vue, or Ionic Angular.

Conclusion

Babylon.js is a powerful, open-source 3D engine capable of rendering interactive 3D and 2D graphics using JavaScript. It is well supported and maintained, providing a good developer experience with many interactive playground examples and a supportive community forum, making it a great choice for creating games, demos, visualizations, and other 3D applications for the web (and eventually even for native platforms as I've heard out of the box React Native support may be coming).

This blog post hopefully gave you an overview of some of its capabilities and how to get started with it along with pointers to more in-depth documentation.

This Dot is a consultancy dedicated to guiding companies through their modernization and digital transformation journeys. Specializing in replatforming, modernizing, and launching new initiatives, we stand out by taking true ownership of your engineering projects.

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About the author(s)

Jan Kaiser
Software engineer passionate about everything web-related. Particularly loves Angular, SCSS, TypeScript, soccer and dachshunds
@honzikec @honzikec

How to build an AI assistant with OpenAI, Vercel AI SDK, and Ollama with Next.js

In today’s blog post, we’ll build an AI Assistant using three different AI models: Whisper and TTS from OpenAI and Llama 3.1 from Meta. While exploring AI, I wanted to try different things and create an AI assistant that works by voice. This curiosity led me to combine OpenAI’s Whisper and TTS models with Meta’s Llama 3.1 to build a voice-activated assistant. Here’s how these models will work together: * First, we’ll send our audio to the Whisper model, which will convert it from speech to text. * Next, we’ll pass that text to the Llama 3.1 model. Llama will understand the text and generate a response. * Finally, we’ll take Llama’s response and send it to the TTS model, turning the text back into speech. We’ll then stream that audio back to the client. Let’s dive in and start building this excellent AI Assistant! Getting started We will use different tools to build our assistant. To build our client side, we will use Next.js. However, you could choose whichever framework you prefer. To use our OpenAI models, we will use their TypeScript / JavaScript SDK. To use this API, we require the following environmental variable: OPENAI_API_KEY— To get this key, we need to log in to the OpenAI dashboard and find the API keys section. Here, we can generate a new key. Awesome. Now, to use our Llama 3.1 model, we will use Ollama and the Vercel AI SDK, utilizing a provider called ollama-ai-provider. Ollama will allow us to download our preferred model (we could even use a different one, like Phi) and run it locally. The Vercel SDK will facilitate its use in our Next.js project. To use Ollama, we just need to download it and choose our preferred model. For this blog post, we are going to select Llama 3.1. After installing Ollama, we can verify if it is working by opening our terminal and writing the following command: Notice that I wrote “llama3.1” because that’s my chosen model, but you should use the one you downloaded. Kicking things off It's time to kick things off by setting up our Next.js app. Let's start with this command: ` After running the command, you’ll see a few prompts to set the app's details. Let's go step by step: * Name your app. * Enable app router. The other steps are optional and entirely up to you. In my case, I also chose to use TypeScript and Tailwind CSS. Now that’s done, let’s go into our project and install the dependencies that we need to run our models: ` Building our client logic Now, our goal is to record our voice, send it to the backend, and then receive a voice response from it. To record our audio, we need to use client-side functions, which means we need to use client components. In our case, we don’t want to transform our whole page to use client capabilities and have the whole tree in the client bundle; instead, we would prefer to use Server components and import our client components to progressively enhance our application. So, let’s create a separate component that will handle the client-side logic. Inside our app folder, let's create a components folder, and here, we will be creating our component: ` Let’s go ahead and initialize our component. I went ahead and added a button with some styles in it: ` And then import it into our Page Server component: ` Now, if we run our app, we should see the following: Awesome! Now, our button doesn’t do anything, but our goal is to record our audio and send it to someplace; for that, let us create a hook that will contain our logic: ` We will use two APIs to record our voice: navigator and MediaRecorder. The navigator API will give us information about the user’s media devices like the user media audio, and the MediaRecorder will help us record the audio from it. This is how they’re going to play out together: ` Let’s explain this code step by step. First, we create two new states. The first one is for keeping track of when we are recording, and the second one stores the instance of our MediaRecorder. ` Then, we’ll create our first method, startRecording. Here, we are going to have the logic to start recording our audio. We first check if the user has media devices available thanks to the navigator API that gives us information about the browser environment of our user: If we don’t have media devices to record our audio, we just return. If they do, then let us create a stream using their audio media device. ` Finally, we go ahead and create an instance of a MediaRecorder to record this audio: ` Then we need a method to stop our recording, which will be our stopRecording. Here, we will just stop our recording in case a media recorder exists. ` We are recording our audio, but we are not storing it anywhere. Let’s add a new useEffect and ref to accomplish this. We would need a new ref, and this is where our chunks of audio data will be stored. ` In our useEffect we are going to do two main things: store those chunks in our ref, and when it stops, we are going to create a new Blob of type audio/mp3: ` It is time to wire this hook with our AudioRecorder component: ` Let’s go to the other side of the coin, the backend! Setting up our Server side We want to use our models on the server to keep things safe and run faster. Let’s create a new route and add a handler for it using route handlers from Next.js. In our App folder, let’s make an “Api” folder with the following route in it: We want to use our models on the server to keep things safe and run faster. Let’s create a new route and add a handler for it using route handlers from Next.js. In our App folder, let’s make an “Api” folder with the following route in it: ` Our route is called ‘chat’. In the route.ts file, we’ll set up our handler. Let’s start by setting up our OpenAI SDK. ` In this route, we’ll send the audio from the front end as a base64 string. Then, we’ll receive it and turn it into a Buffer object. ` It’s time to use our first model. We want to turn this audio into text and use OpenAI’s Whisper Speech-To-Text model. Whisper needs an audio file to create the text. Since we have a Buffer instead of a file, we’ll use their ‘toFile’ method to convert our audio Buffer into an audio file like this: ` Notice that we specified “mp3”. This is one of the many extensions that the Whisper model can use. You can see the full list of supported extensions here: https://platform.openai.com/docs/api-reference/audio/createTranscription#audio-createtranscription-file Now that our file is ready, let’s pass it to Whisper! Using our OpenAI instance, this is how we will invoke our model: ` That’s it! Now, we can move on to the next step: using Llama 3.1 to interpret this text and give us an answer. We’ll use two methods for this. First, we’ll use ‘ollama’ from the ‘ollama-ai-provider’ package, which lets us use this model with our locally running Ollama. Then, we’ll use ‘generateText’ from the Vercel AI SDK to generate the text. Side note: To make our Ollama run locally, we need to write the following command in the terminal: ` ` Finally, we have our last model: TTS from OpenAI. We want to reply to our user with audio, so this model will be really helpful. It will turn our text into speech: ` The TTS model will turn our response into an audio file. We want to stream this audio back to the user like this: ` And that’s all the whole backend code! Now, back to the frontend to finish wiring everything up. Putting It All Together In our useRecordVoice.tsx hook, let's create a new method that will call our API endpoint. This method will also take the response back and play to the user the audio that we are streaming from the backend. ` Great! Now that we’re getting our streamed response, we need to handle it and play the audio back to the user. We’ll use the AudioContext API for this. This API allows us to store the audio, decode it and play it to the user once it’s ready: ` And that's it! Now the user should hear the audio response on their device. To wrap things up, let's make our app a bit nicer by adding a little loading indicator: ` Conclusion In this blog post, we saw how combining multiple AI models can help us achieve our goals. We learned to run AI models like Llama 3.1 locally and use them in our Next.js app. We also discovered how to send audio to these models and stream back a response, playing the audio back to the user. This is just one of many ways you can use AI—the possibilities are endless. AI models are amazing tools that let us create things that were once hard to achieve with such quality. Thanks for reading; now, it’s your turn to build something amazing with AI! You can find the complete demo on GitHub: AI Assistant with Whisper TTS and Ollama using Next.js...

Sep 27, 2024

8 mins

AINextJSJavaScript

The HTML Dialog Element: Enhancing Accessibility and Ease of Use

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This is helpful as it reduces the burden on the developer when making their applications accessible by ensuring that user expectations concerning interaction are met, and it can also potentially simplify the implementation of dialogs in general. Basic usage Adding a dialog using the new tag can be achieved with just a few lines of code. ` However, adding the dialog alone won’t do anything to the page. It will show up only once you call the .showModal() method against it. ` Then if you want to close it you can call the .close() method on the dialog, or press the escape key to close it, just like most other modals work. Also, note how a backdrop appears that darkens the rest of the page and prevents you from interacting with it. Neat! Accessibility and focus management Correctly handling focus is important when making your web applications accessible to all users. Typically you have to move the current focus to the active dialog when showing them, but with the dialog element that’s done for you. By default, the focus will be set on the first focusable element in the dialog. You can optionally change which element receives focus first by setting the autofocus attribute on the element you want the focus to start on, as seen in the previous example where that attribute was added to the close element. Using the .showModal() method to open the dialog also implicitly adds the dialog ARIA role to the dialog element. This helps screen readers understand that a modal has appeared and the screen so it can act accordingly. Adding forms to dialogs Forms can also be added to dialogs, and there’s even a special method value for them. If you add a element with the method set to dialog then the form will have some different behaviors that differ from the standard get and post form methods. First off, no external HTTP request will be made with this new method. What will happen instead is that when the form gets submitted, the returnValue property on the form element will be set to the value of the submit button in the form. So given this example form: ` The form element with the example-form id will have its returnValue set to Submit. In addition to that, the dialog will close immediately after the submit event is done being handled, though not before automatic form validation is done. If this fails then the invalid event will be emitted. You may have already noticed one caveat to all of this. You might not want the form to close automatically when the submit handler is done running. If you perform an asynchronous request with an API or server you may want to wait for a response and show any errors that occur before dismissing the dialog. 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That’s the opposite of what we want to do. Unfortunately, you cannot listen for a click event on the backdrop as it is considered to be part of the dialog itself. Adding this event listener by itself will effectively make clicking anywhere on the page dismiss the dialog. To correct for this we need to wrap the contents of the dialog content with another element that will effectively mask the dialog and receive the click instead. A simple element can do! ` Even this isn’t perfect though as the contents of the div may have elements with margins in them that will push the div down, resulting in clicks close to the edges of the dialog to dismiss it. This can be resolved by adding a couple of styles the the wrapping div that will make the margin stay contained within the wrapper element. The dialog element itself also has some default padding that will exacerbate this issue. ` The wrapping div can be made into an inline-block element to contain the margin, and by moving the padding from the parent dialog to the wrapper, clicks made in the padded portions of the dialog will now interact with the wrapper element instead ensuring it won’t be dismissed. Conclusion Using the dialog element offers significant advantages for creating dialogs and modals by simplifying implementation with reasonable default behavior, enhancing accessibility for users that need assistive technologies such as screen readers by using automatic ARIA role assignment, tailored support for form elements, and flexible styling options....

Oct 25, 2024

4 mins

HTMLJavaScript

How to Run End-to-End Tests on Vercel Preview Deployments

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Sep 20, 2024

3 mins

InfrastructureVercelPlaywrightCypress

Understanding the Difference Between `:focus` and `:focus-visible` in CSS

Understanding the Difference Between :focus and :focus-visible in CSS I have learned my fair share about the importance of keyboard accessibility, so I know that visual indication of the focused element is very important. But the well-known :focus pseudo-class is not always the best fit for this job. That's where :focus-visible comes in. Let's look at the differences between these two pseudo-classes and explore the best practices for using them effectively. What is the :focus Pseudo-Class? The :focus pseudo-class is a CSS selector that applies styles to any element that receives focus, regardless of how that focus was triggered. This includes focus events from keyboard navigation, mouse clicks, and touch interactions. Example Usage of :focus ` In this example, the button will display a blue outline whenever it is focused, whether the user clicks on it with a mouse, taps it on a touchscreen, or navigates to it using the keyboard. What is the :focus-visible Pseudo-Class? The :focus-visible pseudo-class is more specialized. It only applies styles to an element when the browser determines that the focus should be visible. This typically occurs when the user navigates via the keyboard or assistive technologies rather than through mouse or touch input. Example Usage of :focus-visible ` Here, the button will only show a blue outline when focused through keyboard navigation or another input method that usually requires visible focus indicators. Key Differences Between :focus and :focus-visible :focus - Behavior: Applies to any element that receives focus, regardless of the input method. - Use Cases: Ensures that all interactions with the element are visually indicated, whether by mouse, keyboard, or touch. :focus-visible - Behavior: Applies styles only when the focus should be visible, such as using a keyboard or assistive technology. - Use Cases: Ideal for scenarios where you want to provide focus indicators only to keyboard and assistive technology users while avoiding unnecessary outlines for mouse and touch users, typically required by design. Accessibility Implications :focus - Pros: - Guarantees that all users can see when an element is focused, which is critical for accessibility. - Cons: - Can lead to a suboptimal experience for mouse users, as focus styles may appear unnecessarily during mouse interactions. :focus-visible - Pros: - Enhances user experience by showing focus indicators only when necessary, thus keeping the interface clean for mouse and touch users. - Tailors the experience for keyboard and assistive technology users, providing them with clear visual cues. - Cons: - Additional considerations may be required to ensure that focus indicators are not accidentally omitted, especially in older browsers that do not support :focus-visible. - There may be cases where you want to show focus indicators for all users, regardless of input method. Best Practices for Using :focus and :focus-visible To achieve the best accessibility and user experience, combining both :focus and :focus-visible in your CSS is often a good idea. Combining :focus and :focus-visible ` Here is a Stackblitz example of what such styling could look like for you to try out and play with. Additional Tips - Test with Keyboard and Assistive Technology: Ensure that your web application is navigable using a keyboard (Tab, Shift + Tab, etc.) and that focus indicators are visible for those who rely on them. It's never a bad idea to include accessibility testing in your e2e testing suite. - Provide Clear Focus Indicators: Make sure that focus indicators are prominent and easy to see. A subtle or hard-to-spot focus indicator can severely impact accessibility for users who rely on keyboard navigation. Conclusion The :focus-visible pseudo-class offers a more refined way to manage focus indicators, improving accessibility and user experience, particularly for keyboard and assistive technology users. By understanding the differences between :focus and :focus-visible, and applying best practices in your CSS, you can create more accessible and user-friendly web applications. Remember, accessibility should never be an afterthought. By thoughtfully applying focus styles, you ensure that all users, regardless of how they interact with your site, can easily navigate and interact....

Nov 8, 2024

3 mins

AccessibilityCSSPlaywright

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Introduction to Babylon.js

Getting Started

Creating Your First Babylon.js Scene

Creating and Modifying Meshes

Importing and Using Meshes

Making the Scene Interactive

Adding Virtual Reality Support

Adding Physics

Adding Lights

Adding Shadows

Adding Audio

Adding User Interface Elements

Adding Animations

Debugging

Conclusion

Jan Kaiser

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Understanding the Difference Between `:focus` and `:focus-visible` in CSS

Getting Started

Creating Your First Babylon.js Scene

Creating and Modifying Meshes

Importing and Using Meshes

Making the Scene Interactive

Adding Virtual Reality Support

Adding Physics

Adding Lights

Adding Shadows

Adding Audio

Adding User Interface Elements

Adding Animations

Debugging

Hosting and Sharing Your Scene

Conclusion

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