Canvas and SVG are different in applicable scenarios. 1. Canvas is a pixel canvas, suitable for high-performance dynamic drawing, such as games and complex animations, but does not support direct operation of graphic elements; 2. SVG is a vector document, suitable for graphics with clear structure and frequent interactions, such as charts and maps, and supports CSS and JS operations; 3. Canvas performance is better than large-scale graphic rendering, and SVG is more conducive to accessibility and interactive design; 4. Select according to project requirements, if you need to repaint in real time, select SVG.

Canvas and SVG are techniques used to draw graphics on web pages, but they work completely differently from the applicable scenarios.

Canvas is a pixel canvas, SVG is a vector document

Canvas is like a blank canvas. You use JavaScript to "draw dots, connect lines, fill" and finally display pixels one by one. Once you draw it, Canvas doesn't remember what you drew, just keeping the results. In other words, it has no object model and cannot directly manipulate the elements you draw.

SVG (Scalable Vector Graphics) is an XML-based vector graphics format. You can think of it as a structured document where each graphic element can be selected, modified, and bound events. For example, you can use CSS to change its color, or you can use JS to manipulate a circle or rectangle.

Canvas is more suitable if you need to render large amounts of graphics (such as games and animations) in real time with high performance; if you want the graphics to be searched, indexed, scaled without jagging, and easy to interact, then choose SVG.

Canvas is suitable for dynamic drawing, SVG is more suitable for structured graphics

The advantage of Canvas is its flexibility, you can draw frame by frame to achieve complex animation effects, such as particle systems, image filters, etc. But it also has its disadvantages: every time the screen is updated, it must be redrawn, which may not be as efficient as SVG, especially when there are not many graphics but frequent interactions.

SVG is more suitable for content such as icons, charts, and maps with clear structure and high interaction requirements. For example, in data visualization, D3.js often creates interactive charts based on SVG. You can easily add click events to every bar chart or polyline point.

• Canvas: Suitable for complex but static graphics
• SVG: Suitable for scenes with small numbers of graphics but high interactions

Different performance, the choice should be based on specific needs

Canvas performs better when dealing with large amounts of graphics, especially when frequent interactions are not required. Because it operates the pixel directly, it does not create too much DOM node burden.

The performance problems of SVG mainly occur when there are too many graphics, because it essentially creates many nodes in the DOM. If a page has thousands of SVG elements, it may cause the page to stutter.

For example:

• Game development: Canvas is usually used because each frame needs to be re-drawn and the graphics are dense.
• Chart display: Responsive design and interactive features are easier to implement with SVG.

However, many frameworks have been optimized now, such as mixing the two when necessary, or using WebGL to improve the performance limit of Canvas.

Basically that's it. The two technologies have their own strengths and weaknesses, and the key depends on what kind of graphics capabilities and interaction methods your project needs.

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