TrueType/OpenType

摘自：https://www.cnblogs.com/lovelp/p/b1e0ecc5ac8f2852f7eb7fabbc95627f.html

  • TrueType采用几何学中二次B样条曲线及直线来描述字体的外形轮廓，其特点是：TrueType既可以作打印字体，又可以用作屏幕显示；由于它是由指令对字形进行描述，因此它与分辨率无关，输出时总是按照打印机的分辨率输出。无论放大或缩小，字符总是光滑的，不会有锯齿出现。但相对PostScript字体来说，其质量要差一些。特别是在文字太小时，就表现得不是很清楚。
  • OpenType也叫Type 2字体，是由Microsoft和Adobe公司开发的另外一种字体格式。它也是一种轮廓字体，比TrueType更为强大，最明显的一个好处就是可以在把PostScript字体嵌入到TrueType的软件中。并且还支持多个平台，支持很大的字符集，还有版权保护。可以说它是Type 1和TrueType的超集。OpenType的主要优点:
    • 增强的跨平台功能
    • 更好的支持Unicode标准定义的国际字符集
    • 支持高级印刷控制能力
    • 生成的文件尺寸更小
    • 支持在字符集中加入数字签名，保证文件的集成功能

      TTF/OTF/TTC

      摘自：https://www.cnblogs.com/lovelp/p/b1e0ecc5ac8f2852f7eb7fabbc95627f.html
      OpenType标准还定义了OpenType文件名称的后缀名。
  1. 包含TureType字体的OpenType文件后缀名为.ttf
  2. 包含PostScript字体的文件后缀名为.OTF
  3. 如果是包含一系列TrueType字体的字体包文件，那么后缀名为.TTC。 https://www.cnblogs.com/hackermi/p/9291087.html
  • TTF（TrueType Font）是Apple公司和Microsoft公司共同推出的字体文件格式，随着windows的流行，已经变成最常用的一种字体文件表示方式。
  • OTF（OpenType Font）是 TTF 的升级版，而 OTF 是采用的是 PostScript 曲线，支持 OpenType 高级特性的更高级字体。
  • TTC全称是TrueType Collection，它是TrueType字体集成文件(. TTC文件)，是在一单独文件结构中包含多种字体，以便更有效地共享轮廓数据，当多种字体共享同一笔画时，TTC技术可有效地减小字体文件的大小。说白了，TTC就是几个TTF合成的字库，安装后字体列表中会看到两个以上的字体。两个字体中大部分字都一样时，可以将两种字体做成一个TTC文件，常见的TTC字体，因为共享笔划数据，所以大多这个集合中的字体区别只是字符宽度不一样，以便适应不同的版面排版要求。而TTF字体则只包含一种字型。

    字体格式的选择

    基于https://github.com/adobe-fonts/source-han-sans提供的文档：https://github.com/adobe-fonts/source-han-serif/raw/release/download-guide-source-han.pdf，我们可以注意到如下判定流程：
    image.png

image.png
这里的就出现了不同的格式，包括ttc/otf格式。

PostScript/Type 1/TrueType/OpenType

摘自：https://www.adobe.com/cn/products/type/adobe-type-references-tips/font-formats.html

  • What is PostScript?
    • Adobe® PostScript® 3™ is the worldwide printing and imaging standard. The PostScript programming language was originally developed by Adobe Systems to communicate complex graphic printing instructions to digital printers. It is now built into many laser printers for high-quality rendering of both raster and vector graphics. PostScript 编程语言最初是由 Adobe Systems 开发的，用于将复杂的图形打印指令传达给数字打印机。它现在被内置到许多激光打印机中，用于光栅和矢量图形的高质量渲染。
    • An important feature of the PostScript language is that it is device independent. This means that it produces good-looking images regardless of the resolution or color rendering method of the output device, and it takes full advantage of the capabilities built into the device. The Adobe Portable Document Format (PDF) is a more structured, compact subset of the PostScript language. Almost anything that can be done in PostScript can be done in PDF. PostScript 语言的一个重要特征是它与设备无关。这意味着无论输出设备的分辨率或颜色渲染方法如何，它都会产生好看的图像，并且它充分利用了设备内置的功能。Adobe 可移植文档格式 (PDF) 是 PostScript 语言的一个更结构化、更紧凑的子集。几乎任何可以在 PostScript 中完成的事情都可以在 PDF 中完成。
    • Type 1 fonts are a specialized form of PostScript program and are the original file format used for type display on all PostScript printers. The PostScript language was later extended to provide support for the later TrueType and OpenType® font standards. Any new Adobe PostScript language device made today supports all three font standards. Type 1 字体是 PostScript 程序的一种特殊形式，是所有 PostScript 打印机上用于类型显示的原始文件格式。PostScript 语言后来进行了扩展，为后来的 TrueType 和 OpenType ®字体标准提供支持。今天制作的任何新的 Adobe PostScript 语言设备都支持所有三种字体标准。
  • What is Type 1?
    • Adobe PostScript Type 1 is a worldwide standard for digital type fonts (International Standards Organization outline font standard, ISO 9541). It was first developed by Adobe Systems for use in PostScript printers. Although Adobe is a leader in the design and manufacturing of Type 1 software and maintains the standards for Type 1, hundreds of companies around the world have designed and released more than 30,000 fonts in the Type 1 format. Adobe PostScript Type 1 是数字类型字体的全球标准 (国际标准组织大纲字体标准，ISO 9541)。它最初由 Adobe Systems 开发，用于 PostScript 打印机。尽管 Adobe 在 Type 1 软件的设计和制造方面处于领先地位，并保持 Type 1 软件的标准，世界各地的数百家公司已经设计并发布了 30,000 多种 Type 1 格式的字体。
    • The Type 1 font format is recognized on every computer platform, from microcomputers to mainframes. It prints on virtually every printer, either directly through built-in PostScript language interpreting, or through add-on utilities, such as Adobe Type Manager® (ATM®). ATM technology is integrated into Microsoft® Windows® 2000 and Mac OSX operating system. For more than a decade, Type 1 has been the preferred format for the graphic arts and publishing industries. 从微型计算机到大型机，每个计算机平台都可以识别 Type 1 字体格式。它可以直接通过内置的 PostScript 语言解释或通过附加实用程序 (如 Adobe Type Manager® (ATM®)) 在几乎所有打印机上打印。ATM 技术集成到Microsoft® Windows® 2000 和 Mac OSX 操作系统。十多年来，Type 1 一直是图形艺术和出版行业的首选格式。
  • What is TrueType?
    • TrueType is a standard for digital type fonts that was developed by Apple Computer, and subsequently licensed to Microsoft Corporation. Each company has made independent extensions to TrueType, which is used in both Windows and Macintosh operating systems. Like Type 1, the TrueType format is available for development of new fonts. TrueType 是数字字体的标准，由苹果电脑开发，随后被许可给微软公司。每个公司都对 TrueType 进行了独立的扩展，TrueType 同时用于 Windows 和 Macintosh 操作系统。与 Type 1 一样，TrueType 格式可用于开发新字体。
  • What is OpenType?
    • OpenType is a new standard for digital type fonts, developed jointly by Adobe and Microsoft. OpenType supersedes Microsoft’s TrueType Open extensions to the TrueType format. OpenType fonts can contain either PostScript or TrueType outlines in a common wrapper. An OpenType font is a single file, which can be used on both Macintosh and Windows platforms without conversion. OpenType fonts have many advantages over previous font formats because they contain more glyphs, support more languages (OpenType uses the Unicode standard for character encoding,) and support rich typographic features such as small caps, old style figures, and ligatures — all in a single font. OpenType 是数字类型字体的新标准，由 Adobe 和微软联合开发。OpenType 取代微软的 TrueType 开放扩展到 TrueType 格式。OpenType 字体可以在通用包装中包含 PostScript 或 TrueType 轮廓。OpenType 字体是单个文件，无需转换即可在 Macintosh 和 Windows 平台上使用。与以前的字体格式相比，OpenType 字体具有许多优势，因为它们包含更多的字形，支持更多的语言 (OpenType 使用 Unicode 标准进行字符编码)，并支持丰富的排版功能，如小帽，旧风格的人物和连字 —— 全部用一种字体。
    • Beginning with Adobe InDesign® and Adobe Photoshop® 6.0, applications have begun to support OpenType layout features. OpenType layout allows you to access features such as old style figures or true small caps by simply applying formatting to text. In most applications that do not actively support such features, OpenType fonts work just like other fonts, although the OpenType layout features are not accessible. 从 Adobe InDesign®和 Adobe Photoshop®6.0 开始，应用程序已经开始支持 OpenType 布局功能。OpenType 布局允许您通过简单地将格式应用于文本来访问功能，例如旧样式图形或真正的小大写字母。在大多数不主动支持此类功能的应用程序中，OpenType 字体与其他字体一样工作，尽管 OpenType 布局功能不可访问。
    • OpenType with PostScript outlines is supported by the latest versions of Adobe Type Manager, and is natively supported in Windows 2000. Apple has also announced its intent to support OpenType, and supplies Japanese system fonts for Mac OS X in OpenType form with PostScript outlines. 最新版本的 Adobe Type Manager 支持带有 PostScript 大纲的 OpenType，并且在 Windows 2000 中受支持。苹果还宣布了其支持 OpenType 的意图，并以 OpenType 的形式为 Mac OS X 提供带有 PostScript 轮廓的日语系统字体。