However, glyphs from different scripts in this font may not appear correctly aligned relative to each other when used with applications that either don’t support the 'BASE' table or that support it but assume that a particular baseline will not vary across scripts. This situation could arise when a developer makes a Unicode font, for example, by combining glyphs from fonts that use different baseline systems. The 'BASE' table allows for different scripts in the font to specify different values for the same baseline tag. Creative shapes, like swirls or other symbols, may not be recognized by users as indicating that a glyph is missing from the font and is not being displayed at that location. notdef glyph be either an empty rectangle, a rectangle with a question mark inside of it, or a rectangle with an “X”. This glyph should not be left without an outline as the user will only see what looks like a space if a glyph is missing and not be aware of the active font’s limitation. notdef glyph is very important for providing the user feedback that a glyph is not found in the font. Characters U+0009 and U+0020 should map to a glyph with the same width.Characters U+0009 (horizontal tabulation), U+0020 (space) and U+00A0 (no-break space) should map to a glyph with no contours and a positive advance width.
#HOW TO TYPE FONT GLYPHS WINDOWS#
These glyphs are recommended to allow for the same version of the font to work on both Windows and Macintosh. These were listed in Apple’s original TrueType specification. TrueType outline fonts should have the following four glyphs at the glyph ID indicated. Any extra space after a table (and before the next LONG word boundry) should be padded with zeros. To ensure that checksums are calculated correctly, it is suggested that tables begin on LONG word boundries. While this is not required by the TrueType rasterizer, it does prevent ambiguous checksum calculations and greatly speeds table access on some processors.Īll tables should be recorded in the table directory with their actual length. Table Alignment and LengthĪll tables should be aligned to begin at offsets which are multiples of four bytes.
#HOW TO TYPE FONT GLYPHS SOFTWARE#
In all cases, software must determine the kind of outlines present in a font not from the filename extension but from the contents of the file. TTC may be used for CFF Font Collections if needed for backward compatibility with older software that was not aware of the. OTC whether or not the fonts have OFF layout tables present, and regardless of the kind of outlines present.
A Font Collection file should have filename extension.TTF extension, depending on the desire for backward compatibility on older systems or with previous versions of the font A standalone font file with TrueType outlines should have either.TTC, depending on the type of outlines in the font and the desired backwards compatibility. Choose the format that meets your feature requirements. Mixing Outline Formatsīoth Microsoft and Adobe recommend against mixing outline formats within a single font. OpenType fonts containing CFF data should use the tag 'OTTO' as the sfnt version number. OpenType fonts that contain TrueType outlines should use the value of 1.0 for the sfnt version. Byte OrderingĪll OpenType fonts use Motorola-style byte ordering (Big Endian). This chapter outlines recommendations for creating OpenType fonts.