DirectWrite defines the following macros.
In this section
|DWRITE_MAKE_FONT_AXIS_TAG||Creates an OpenType tag for a font axis.|
|DWRITE_MAKE_OPENTYPE_TAG||Creates an OpenType tag as a 32-bit integer, such that the first character in the tag is the lowest byte (least significant on little endian architectures), which can be used to compare with tags in the font file. This macro is compatible with DWRITE_FONT_FEATURE_TAG.|