linefold
Convert given text into folded lines with maximum width and given font / given text length measuring function before rendering, so as to render paragraphs onto platforms without line-folding support, e.g. HTML5 Canvas.
This tool only supports languages like English, French, German, Russian, Chinese, Japanese, Korean, etc. Text with complex scripts (e.g. Arabic, Hebrew, Hindi, Thai) not supported.
Loading
WebPack
import linefold from 'linefold';
Node.js
const linefold = require('linefold');
Script Tag
<script type='text/javascript' src='./dist/linefold.js'></script>
Usage
linefold(text,max_length,font);
linefold(text,max_length,(text)=>{
//Your function for measuring text length
return text.length;
});
Examples
Default text length measuring function based on HTML Canvas, with text length in pixel:
var text='Convert given text into folded lines with given font and maximum width before rendering, so as to render paragraphs onto platforms without line-folding support, e.g. HTML5 Canvas.';
var lines=linefold(text,320,'16px Times New Roman');
/*
Folding result:
[
"Convert given text into folded lines with given",
"font and maximum width before rendering, so as",
"to render paragraphs onto platforms without line-",
"folding support, e.g. HTML5 Canvas."
]
*/
Fold text under terminal environment with maximum width of 36 rows:
var text='Convert given text into folded lines with given font and maximum width before rendering, so as to render paragraphs onto platforms without line-folding support, e.g. HTML5 Canvas.';
var lines=linefold(text,36,(text)=>{
let len=0;
for(let char of text){
len += (/[\u4E00-\u9FA5\u3000-\u303f\uFF01-\uFF5E]+/.test(char) ? 2 : 1);
}
return len;
});
/*
Folding result:
[
"Convert given text into folded lines",
"with given font and maximum width",
"before rendering, so as to render",
"paragraphs onto platforms without",
"line-folding support, e.g. HTML5",
"Canvas."
]
*/
Fold text with Chinese characters under terminal environment (each Chinese characters and punctions takes space of 2 characters):
var text='根据给定的文本、最大宽度、字体等条件，对一段文本进行换行操作。然后渲染到一些不支持自动换行的环境上，比如HTML5 Canvas。';
var lines=linefold(text,36,(text)=>{
let len=0;
for(let char of text){
len += (/[\u4E00-\u9FA5\u3000-\u303f\uFF01-\uFF5E]+/.test(char) ? 2 : 1);
}
return len;
});
/*
Folding result:
[
"根据给定的文本、最大宽度、字体等条",
"件，对一段文本进行换行操作。然后渲染",
"到一些不支持自动换行的环境上，比如",
"HTML5 Canvas。"
]
*/
linefold
根据给定的文本、最大宽度、字体/文本长度测量函数，对一段文本进行换行操作。用于将文本渲染到一些不支持自动换行的环境上，比如HTML5 Canvas。
本工具仅支持英语、法语、德语、俄语、中日韩文字等文字。不支持含有复杂文字（如希伯来语、阿拉伯语、印地语、泰语）的文本。
引入
WebPack
import linefold from 'linefold';
Node.js
const linefold = require('linefold');
Script Tag
<script type='text/javascript' src='path/to/linefold.js'></script>
使用方法
linefold(text,max_length,font);
linefold(text,max_length,(text)=>{
//自定义文本长度测量函数
return text.length;
});
范例
浏览器中使用默认的基于HTML Canvas的文本长度测量方式，单位为像素：
var text='根据给定的文本、最大宽度、字体等条件，对一段文本进行换行操作。然后渲染到一些不支持自动换行的环境上，比如HTML5 Canvas。';
var lines=linefold(text,320,'16px 宋体');
/*
换行结果：
[
"根据给定的文本、最大宽度、字体等条件，对",
"一段文本进行换行操作。然后渲染到一些不支",
"持自动换行的环境上，比如HTML5 Canvas。"
]
*/
终端环境下将文本按最宽36列进行换行（中文字符和中文标点符号占2个字符的位置）：
var text='根据给定的文本、最大宽度、字体等条件，对一段文本进行换行操作。然后渲染到一些不支持自动换行的环境上，比如HTML5 Canvas。';
var lines=linefold(text,36,(text)=>{
let len=0;
for(let char of text){
len += (/[\u4E00-\u9FA5\u3000-\u303f\uFF01-\uFF5E]+/.test(char) ? 2 : 1);
}
return len;
});
/*
换行结果：
[
"根据给定的文本、最大宽度、字体等条",
"件，对一段文本进行换行操作。然后渲染",
"到一些不支持自动换行的环境上，比如",
"HTML5 Canvas。"
]
*/
