truetype字体的字形和指标|爪哇

获取字体指标

字体指标是指Informaiton，例如ascender，’descender，typoAscender，TypoDescender和’unitSperem`。 Java 版 Aspose.Font API可用于打开TTF字体文件，并使用以下示例代码从这些文件中读取字体指标信息。

// For complete examples and data files, please go to https://github.com/aspose-font/Aspose.Font-for-Java
String fileName = Utils.getDataDir() + "Montserrat-Regular.ttf"; //Font file name with full path

      FontDefinition fd = new FontDefinition(FontType.TTF, new FontFileDefinition("ttf", new FileSystemStreamSource(fileName)));
      TtfFont font = (TtfFont) Font.open(fd);

      String name = font.getFontName();
      System.out.println("Font name: " + name);
      System.out.println("Glyph count: " + font.getNumGlyphs());
      String metrics = MessageFormat.format(
          "Font metrics: ascender - {0}, descender - {1}, typo ascender = {2}, typo descender = {3}, UnitsPerEm = {4}",
          font.getMetrics().getAscender(), font.getMetrics().getDescender(),
          font.getMetrics().getTypoAscender(), font.getMetrics().getTypoDescender(), font.getMetrics().getUnitsPerEM());

      System.out.println(metrics);
      
    //Get cmap unicode encoding table from font as object TtfCMapFormatBaseTable to access information about font glyph for symbol 'A'.
      //Also check that font has object TtfGlyfTable (table 'glyf') to access glyph.
      TtfCMapFormatBaseTable cmapTable = null;
      if (font.getTtfTables().getCMapTable() != null)
      {
          cmapTable = font.getTtfTables().getCMapTable().findUnicodeTable();
      }
      if (cmapTable != null && font.getTtfTables().getGlyfTable() != null)
      {
      	System.out.println("Font cmap unicode table: PlatformID = " + cmapTable.getPlatformId() +
      			", PlatformSpecificID = " + cmapTable.getPlatformSpecificId());

          //Code for 'A' symbol
          char unicode = (char)65;

          //Glyph index for 'A'
          long glIndex = cmapTable.getGlyphIndex(unicode);

          if (glIndex != 0)
          {
              //Glyph for 'A'
              Glyph glyph = font.getGlyphById(glIndex);
              if (glyph != null)
              {
                  //Print glyph metrics
              	System.out.println("Glyph metrics for 'A' symbol:");
                  String bbox = MessageFormat.format(
                      "Glyph BBox: Xmin = {0}, Xmax = {1}" + ", Ymin = {2}, Ymax = {3}",
                      glyph.getGlyphBBox().getXMin(), glyph.getGlyphBBox().getXMax(),
                      glyph.getGlyphBBox().getYMin(), glyph.getGlyphBBox().getYMax());
                  System.out.println(bbox);
                  System.out.println("Width:" + font.getMetrics().getGlyphWidth(new GlyphUInt32Id(glIndex)));
              }
          }
      }

检测拉丁符号

aspose.font for .api允许您从truetype字体文件中检测拉丁符号。这可以使用以下示例代码来实现。

• 使用fontfiledefinition加载字体文件
• 使用DecodeTogid()方法解码滑翔机

// For complete examples and data files, please go to https://github.com/aspose-font/Aspose.Font-for-Java
String fileName = Utils.getDataDir() + "Montserrat-Regular.ttf"; //Font file name with full path

      FontDefinition fd = new FontDefinition(FontType.TTF, new FontFileDefinition("ttf", new FileSystemStreamSource(fileName)));
      TtfFont ttfFont = (TtfFont) Font.open(fd);

      boolean latinText = true;


      for (int code = 65; code < 123; code++)
      {
          GlyphId gid = ttfFont.getEncoding().decodeToGid(code);
          if (gid == null || gid == GlyphUInt32Id.getNotDef())
          {
              latinText = false;
          }
      }

      if (latinText)
      {
          System.out.println(MessageFormat.format("Font {0} supports latin symbols.", ttfFont.getFontName()));
      }
      else
      {
      	System.out.println(MessageFormat.format("Latin symbols are not supported by font {0}.", ttfFont.getFontName()));
      }

提取许可限制

使用Java 版 Aspose.Font API从字体文件中提取许可限制。字体可以在以下模式之一中具有嵌入其中的许可信息。

• “可编辑嵌入” - 字体可以嵌入，也可以临时加载到其他系统。此外，允许编辑，包括使用嵌入字体格式化新文本，并保存更改。
• “可安装嵌入” - 字体可以嵌入，也可以永久安装到远程系统或其他用户使用。
• “预览和打印嵌入” - 字体可以嵌入，也可以临时加载到其他系统，以便查看或打印文档。
• “受限嵌入” - 未经合法所有者明确许可，不得以任何方式修改、嵌入或交换字体。

以下代码示例显示了如何以方便的形式使用对象aspose.font.ttf.licenseflags以获取有关字体许可限制(来自表OS/2的FLAG FSTYPE)的信息。

// For complete examples and data files, please go to https://github.com/aspose-font/Aspose.Font-for-Java
String fileName = Utils.getDataDir() + "Montserrat-Regular.ttf"; //Font file name with full path

      FontDefinition fd = new FontDefinition(FontType.TTF, new FontFileDefinition("ttf", new FileSystemStreamSource(fileName)));
      TtfFont font = (TtfFont) Font.open(fd);

      LicenseFlags licenseFlags = null;
      if (font.getTtfTables().getOs2Table() != null)
      {
          licenseFlags = font.getTtfTables().getOs2Table().getLicenseFlags();
      }

      if (licenseFlags == null || licenseFlags.isFSTypeAbsent())
      {
          System.out.println(MessageFormat.format("Font {0} has no embedded license restrictions", font.getFontName()));
      }
      else
      {
          if (licenseFlags.isEditableEmbedding())
          {
          	System.out.println(MessageFormat.format("Font {0} may be embedded, and may be temporarily loaded on other systems.", font.getFontName())
                  + " In addition, editing is permitted, including ability to format new text"
                  + " using the embedded font, and changes may be saved.");
          }
          else if (licenseFlags.isInstallableEmbedding())
          {
          	System.out.println(MessageFormat.format("Font {0} may be embedded, and may be permanently installed", font.getFontName())
                  + " for use on a remote systems, or for use by other users.");
          }
          else if (licenseFlags.isPreviewAndPrintEmbedding())
          {
          	System.out.println(MessageFormat.format("Font {0} may be embedded, and may be temporarily loaded", font.getFontName())
                  + "  on other systems for purposes of viewing or printing the document.");
          }
          else if (licenseFlags.isRestrictedLicenseEmbedding())
          {
          	System.out.println(MessageFormat.format("Font {0} must not be modified, embedded or exchanged in any manner", font.getFontName())
                  + " without first obtaining explicit permission of the legal owner.");
          }
      }