In Unicode, some characters are “mirrored”. This means that their images are mirrored horizontally in text that is laid out from right to left. For instance, “(” would become its mirror image, “)”, in right-to-left text.
ch has the Unicode mirrored property and there is another unicode
character that typically has a glyph that is the mirror image of
mirrored_ch is set, it puts that character in the address
pointed to by
mirrored_ch. Otherwise the original character is put.
A Unicode character.
Location to store the mirrored character.
The data is owned by the caller of the function.