requestAnimationFrame (rAF) is more suitable for animation than setTimeout or setInterval because it synchronizes with the browser refresh mechanism to achieve smoother and more efficient animation effects. ① rAF will call the specified function before the browser's next repaint, usually execute at a frequency of 60 frames per second to make the animation smoother; ② It will automatically pause when the tab page is not in the foreground to save resources; ③ When using it, start the animation loop by calling requestAnimationFrame recursively and stop avoiding memory leaks under appropriate conditions; ④ Pay attention to avoid frequent operation of DOM It is recommended to use high-performance properties such as transform and can use the timestamps received by the callback function for precise control; ⑤ Mainstream browsers have been widely supported but are compatible with old browsers that may require polyfill.
requestAnimationFrame
( rAF
for short) is an API provided by a browser that is specifically used to perform animation-related operations before page repainting. It does not simply make the animation "move", but helps you achieve animation effects more efficiently and smoothly.
Why is it more suitable for animation than setTimeout or setInterval?
Many people use setTimeout
or setInterval
to control the rhythm of animation, but these methods are not always synchronized with the browser's refresh mechanism. The result is: animations may stutter, skip frames, and even affect performance.
What's special about requestAnimationFrame
is that:
- It will tell the browser: "I'm going to do the animation next, you prepare and call my function before the next repaint."
- The browser will execute your code at the right time, usually 60 times per second (that is, one frame around 16.7ms), so that the animation looks smoother.
- If the tab page is not in the foreground (such as the user switches the browser tab), it will automatically pause, saving resources.
How to write a simple animation using requestAnimationFrame?
The basic usage is actually very simple. It accepts a callback function as a parameter, and this function will be called in the next frame.
For example: You want an element to move from left to right.
function animate() { // Do something to update location/style element.style.left = newX 'px'; // Continue to requestAnimationFrame(animate); } // Start the animation requestAnimationFrame(animate);
The key point of this code is to call yourself "recursively" and constantly request the next frame until you stop actively (for example, by conditional judgment, no longer call requestAnimationFrame
).
Some tips and precautions for using it
- Don't operate DOM frequently in it : Although rAF is a good tool for optimizing animations, if you operate DOM in large quantities every frame, it will still affect performance. It is recommended to batch processing or use high-performance properties such as transform.
- You can pass a timestamp to the callback function : the callback function receives a parameter to represent the current timestamp (unit is milliseconds). You can use this to do more precise animation control.
- Remember to clean up unnecessary animation loops : for example, when component uninstallation, unfinished rAF requests may be cancelled, otherwise memory leaks may occur.
- Compatibility is already very good : mainstream browsers support it, but if you want to be compatible with very old browsers, you may need to add a prefix or polyfill.
Ending
In general, requestAnimationFrame
is one of the foundations of modern web animation. It not only makes animations smoother, but also helps us write better performance code. If you use it too much, you will find that it is not complicated, but it is indeed easy to ignore details.
The above is the detailed content of What is requestAnimationFrame. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

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)

React itself does not directly manage focus or accessibility, but provides tools to effectively deal with these issues. 1. Use Refs to programmatically manage focus, such as setting element focus through useRef; 2. Use ARIA attributes to improve accessibility, such as defining the structure and state of tab components; 3. Pay attention to keyboard navigation to ensure that the focus logic in components such as modal boxes is clear; 4. Try to use native HTML elements to reduce the workload and error risk of custom implementation; 5. React assists accessibility by controlling the DOM and adding ARIA attributes, but the correct use still depends on developers.

Shallowrenderingtestsacomponentinisolation,withoutchildren,whilefullrenderingincludesallchildcomponents.Shallowrenderingisgoodfortestingacomponent’sownlogicandmarkup,offeringfasterexecutionandisolationfromchildbehavior,butlacksfulllifecycleandDOMinte

StrictMode does not render any visual content in React, but it is very useful during development. Its main function is to help developers identify potential problems, especially those that may cause bugs or unexpected behavior in complex applications. Specifically, it flags unsafe lifecycle methods, recognizes side effects in render functions, and warns about the use of old string refAPI. In addition, it can expose these side effects by intentionally repeating calls to certain functions, thereby prompting developers to move related operations to appropriate locations, such as the useEffect hook. At the same time, it encourages the use of newer ref methods such as useRef or callback ref instead of string ref. To use Stri effectively

Create TypeScript-enabled projects using VueCLI or Vite, which can be quickly initialized through interactive selection features or using templates. Use tags in components to implement type inference with defineComponent, and it is recommended to explicitly declare props and emits types, and use interface or type to define complex structures. It is recommended to explicitly label types when using ref and reactive in setup functions to improve code maintainability and collaboration efficiency.

Server-siderendering(SSR)inNext.jsgeneratesHTMLontheserverforeachrequest,improvingperformanceandSEO.1.SSRisidealfordynamiccontentthatchangesfrequently,suchasuserdashboards.2.ItusesgetServerSidePropstofetchdataperrequestandpassittothecomponent.3.UseSS

WebAssembly(WASM)isagame-changerforfront-enddevelopersseekinghigh-performancewebapplications.1.WASMisabinaryinstructionformatthatrunsatnear-nativespeed,enablinglanguageslikeRust,C ,andGotoexecuteinthebrowser.2.ItcomplementsJavaScriptratherthanreplac

Vite or VueCLI depends on project requirements and development priorities. 1. Startup speed: Vite uses the browser's native ES module loading mechanism, which is extremely fast and cold-start, usually completed within 300ms, while VueCLI uses Webpack to rely on packaging and is slow to start; 2. Configuration complexity: Vite starts with zero configuration, has a rich plug-in ecosystem, which is suitable for modern front-end technology stacks, VueCLI provides comprehensive configuration options, suitable for enterprise-level customization but has high learning costs; 3. Applicable project types: Vite is suitable for small projects, rapid prototype development and projects using Vue3, VueCLI is more suitable for medium and large enterprise projects or projects that need to be compatible with Vue2; 4. Plug-in ecosystem: VueCLI is perfect but has slow updates,

Immutable updates are crucial in React because it ensures that state changes can be detected correctly, triggering component re-rendering and avoiding side effects. Directly modifying state, such as push or assignment, will cause React to be unable to detect changes. The correct way to do this is to create new objects instead of old objects, such as updating an array or object using the expand operator. For nested structures, you need to copy layer by layer and modify only the target part, such as using multiple expansion operators to deal with deep attributes. Common operations include updating array elements with maps, deleting elements with filters, adding elements with slices or expansion. Tool libraries such as Immer can simplify the process, allowing "seemingly" to modify the original state but generate new copies, but increase project complexity. Key tips include each
