quark-renderer
v1.0.45
Published
A lightweight yet powerful canvas (&svg) render engine improved from ZRender.
Downloads
17
Readme
A lightweight yet powerful Canvas(&SVG) render engine improved from ZRender
Home page https://quark-renderer.gitee.io
Background
Important: Quark Renderer is not built from scratch, but improved from ZRender, which is the render engine behind ECharts.
I have used ECharts and ZRender for many years, both of them are extremly powerful tools for making some charting stuff.
To better understand the core ideas behind ZRender, I spent some days (2020-01) to read through its source code. In this process, I refactored a bunch of code and comments, because:
- I want a very customized version to implement some cool stuff in the future.
- I want a cleaner repo to teach my students how to understand and design a canvas engine for modern web and Wechat mini-programs.
- I want to make the code easier to read.
- There are two reasons why I have to pick up a new name for this project. Firstly, ZRender exported a global variable 'zrender', therefore a new name can avoid potential conflicts. Secondly, duplicated names are not allowed in npm registry.
Here are the key improvements compare to the original ZRender:
- Modified a bunch of classes and .js files with ES6 syntax.
- Added keyboard event support.
- Added multi drag-drop feature.
- Refactored the structure of .js files and directories for better understanding.
- Refactored some implementation details for better understanding.
- Fixed some bugs in /test directory, added a few test cases.
- Use jsduck for better API documentation.
- Refactored all the comments for jsduck.
- Support Wechat mini-program directly, do not need any hack.
- Support node-canvas environment directly, do not need any hack.
- Removed VML engine, because MicroSoft has abandoned this engine since 2012, by removing VML module we can make the bundle of QuarkRenderer smaller.
- Added skew feature for transformation system.
- Added transform control for elements.
- Added link control for lines and shapes including a Microsoft Visio like link line, so we can link these elements now.
- Refactored Group so that it can be nested and restrict the position of child nodes.
Usage
- Pull this repo to your local device.
- Run npm build.
- Check the examples inside /test directory.
Browser example:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Animation</title>
<script src="../dist/quark-renderer.js"></script>
<meta name="viewport" content="width=device-width, initial-scale=1" />
<style>
html,
body,
#main {
width: 100%;
height: 100%;
}
</style>
</head>
<body>
<div id="main"></div>
<script type="text/javascript">
let main = document.getElementById('main');
let qr = QuarkRenderer.init(main);
let gradient = new QuarkRenderer.LinearGradient();
gradient.addColorStop(0, 'red');
gradient.addColorStop(1, 'black');
let circle = new QuarkRenderer.Circle({
position: [0, 0],
scale: [1, 1],
shape: {
cx: 50,
cy: 50,
r: 50,
},
style: {
fill: gradient,
lineWidth: 5,
text: 'circle',
textPosition: 'inside',
},
});
qr.add(circle);
// first animation process
circle
.animate()
.when(1000, {
position: [200, 0],
scale: [2, 1],
})
.when(2000, {
position: [200, 200],
scale: [1, 1],
})
.when(3000, {
position: [0, 200],
scale: [1, 2],
})
.when(4000, {
position: [0, 0],
scale: [1, 1],
})
.during(function () {
console.log(circle.animationProcessList.length);
})
.done(function () {
console.log(circle.animationProcessList.length);
})
.start(); //.start(true)
//second animation process
circle
.animate()
.when(1000, {
position: [500, 0],
scale: [2, 1],
})
.when(2000, {
position: [200, 200],
scale: [1, 1],
})
.when(3000, {
position: [0, 200],
scale: [1, 2],
})
.when(4000, {
position: [0, 0],
scale: [1, 1],
})
.during(function () {
console.log(circle.animationProcessList.length);
})
.done(function () {
console.log(circle.animationProcessList.length);
})
.start(); //.start(true)
</script>
</body>
</html>Wechat mini-program example:
<view class="page">
<view class="page__hd">
<view class="page__title">Quark Renderer 小程序示例1</view>
</view>
<view class="page__bd page__bd_spacing">
<view style="width:100%;height:500px;">
<canvas style="width: 300px; height: 500px;" canvas-id="firstCanvas"></canvas>
</view>
</view>
</view>onReady: function () {
let ctx = wx.createCanvasContext('firstCanvas');
//注意这里的初始化参数，因为微信小程序不允许操作 DOM，所以引擎不能自动获取到宽度高度，这里需要手动传进去
let qr = QuarkRenderer.init(ctx,{width:300,height:500,renderer:'canvas'});
let polygon = new QuarkRenderer.Polygon({
position: [100, 100],
scale: [1, 1],
style: {
fill: 'red'
}
});
setInterval(function () {
let len = Math.round(Math.random() * 100);
let points = [];
let r = (Math.random() * 100);
for (let i = 0; i <= len; i++) {
let phi = i / len * Math.PI * 2;
let x = Math.cos(phi) * r + 100;
let y = Math.sin(phi) * r + 100;
points.push([x, y]);
}
polygon.animateTo({
shape: {
points: points
}
}, 500, 'cubicOut');
}, 1000);
qr.add(polygon);
}Document
The document is in /api directory, open /api/index.html in your browser then you can see a beautiful API document just like Sencha(ExtJS).
ScreenShots
Wechat mini-program example:
Resources
https://cloud.tencent.com/edu/learning/live-1902?ADTAG=xyj
License
BSD 3-Clause License