canvas API, popular canvas basics (1)

Before I learned canvas, I felt that canvas was so mysterious, so gorgeous, and so profound. The effects made with canvas were so cool and the things it could do were so broad. It just filled me with awe. , I often sigh: If I get this skill, I will definitely go to heaven (note, this is not about going to heaven). The main reason why I never dared to get involved at that time is that, first, in the era when compatibility with IE is still needed, compatibility is hard. injury; second, reference

canvas API, popular canvas basic knowledge (2)

Above we talked about drawing a line, drawing a rectangle, and writing text. Finally, we have a good beginning. If you haven’t read it yet, go out and turn left. Read that article first. I won’t go into details here. Next Let’s look at some more complex properties and methods! Before I talk about it, I still want to review it. After all, there are a few attributes that I haven’t mentioned above, so let’s start by drawing a triangle! If you read the above, the clever young man will definitely think that triangles are more

canvas API, popular canvas basics (3)

The full text talks about how to draw triangles, circles and other related graphics. Students who are not familiar with it can go out and turn right, read the previous text first, and then continue with our graphics - curves. Students who have studied mathematics or are familiar with js all know the Bezier curve. Of course, in mathematics, this is a profound knowledge. The Bezier curve in js is generally used for animation. In fact, other It is also reflected in places, such as Photoshop

How to use html5 and css3 to complete google graffiti animation

Html5 simply implements the sample code of graffiti board

This article mainly teaches you how to use Html5 to write your own drawing board to perform painting, color adjustment and other operations. Interested friends can refer to it. I recently learned that the powerful drawing function of HTML5 surprised me, so I wrote this Gadget---graffiti board, which can realize functions such as: drawing, changing color, adjusting brush size. HTML5 drawing can be divided into points, lines, surfaces, circles, pictures, etc. Points and lines are the basic points of all plane effects. With these two things, there is nothing that cannot be drawn, only unexpected algorithms.

Detailed introduction of HTML5+CSS3 to realize drag-and-drop upload of images without plug-in (supports preview and batch)

This article mainly introduces HTML5+CSS3 to implement drag-and-drop uploading of images without plug-ins (supporting preview and batch). Now html5 provides API and powerful APIs such as File, FileReader, XMLHttpRequest, etc., which makes it possible for us to achieve drag-and-drop uploading. Those who are interested can find out.

Briefly introduce the difference between HTML5 defer and async

The editor below will bring you a brief discussion on the difference between HTML5 defer and async. The editor thinks it is quite good, so I will share it with you now and give it as a reference for everyone. Let’s follow the editor and take a look.

Sharing the basic usage of postMessage API in HTML5

window.postMessage is often used by people for cross-domain data transfer. The following will introduce the basic usage tutorial of postMessage API in HTML5. Friends who need it can refer to it.

Detailed explanation of how to use HTML5's Geolocation API

Geolocation is one of the important features of HTML5. It provides the function of determining the user's location. With this feature, applications based on location information can be developed. Today's article will introduce to you a tutorial on how to use HTML5's Geolocation API. .

Code example sharing for using drawImage() method in HTML5 Canvas API (picture)

This article mainly introduces the usage examples of the drawImage() method in the HTML5 Canvas API. The drawImage() method is mainly used to scale or crop images. The article gives the usage of its coordinates and related parameters. Friends who need it can refer to it.

Code example for cropping an area image using the clip() method in the HTML5 Canvas API

This article mainly introduces an example tutorial of using the clip() method in the HTML5 Canvas API to crop an area image. Special attention needs to be paid to the use of the save() and restore() methods. Friends in need can refer to the following

Detailed introduction to html5 multimedia

1) Attributes of the video element: autoplay - if present, this attribute will cause the browser to start playing the video as soon as possible; preload=none - the video will not be loaded before the user starts playing the video; preload=metadata - the user starts playing the video Previously, only the video's metadata could be loaded; preload=auto - Requests the browser to download the entire video as quickly as possible. The browser can ignore this request. This is the default behavior; controls—unless this attribute is present, no

Detailed explanation of code examples for getting started with HTML5 canvas (picture)

1) Members of the HTMLCanvasElement object: height - corresponds to the height attribute of the canvas element; width - corresponds to the width attribute of the canvas element; getContext() - returns the drawing context for the canvas; 2) Draw a rectangle: fillRect(x,y ,w,h)——Draw a solid rectangle; strokeRect(x,y,w,h)——Draw a hollow rectangle;

Detailed code explanation of HTML5 canvas advanced code (picture)

1) Draw with a path: beginPath() - start a new path; closePath() - try to close an existing path by drawing a line connecting the end point of the last line with the initial coordinates; fill() - fill Graphics described by sub-paths; isPointInPath(x,y) - returns true if the specified point is within the graphics described by the current path; lineTo(x,y) - draws a sub-path to the specified coordinates;