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CHAPTER 5                                                                     Text



The following is an example of a W entry:

  /W [ 120 [ 400 325 500 ]
       7080 8032 1000
     ]

In this example, the glyphs having CIDs 120, 121, and 122 are 400, 325, and 500
units wide, respectively. CIDs in the range 7080 through 8032 all have a width of
1000 units.

Glyphs from a CIDFont can be shown in vertical writing mode. (This is selected
by the WMode entry in the associated CMap dictionary; see Section 5.6.4,
“CMaps.”) To be used in this way, the CIDFont must define the vertical dis-
placement for each glyph and the position vector that relates the horizontal and
vertical writing origins.

The default position vector and vertical displacement vector are specified by the
DW2 entry in the CIDFont dictionary. DW2 is an array of two values: the vertical
component of the position vector v and the vertical component of the displace-
ment vector w1 (see Figure 5.5 on page 396). The horizontal component of the
position vector is always half the glyph width, and that of the displacement vector
is always 0. For example, if the DW2 entry is

  / DW2 [ 880 −1000 ]

then a glyph’s position vector and vertical displacement vector are
 v = (w0 ÷ 2, 880)
w1 = (0, – 1000)

where w0 is the width (horizontal displacement) for the same glyph. Note that a
negative value for the vertical component places the origin of the next glyph be-
low the current glyph because vertical coordinates in a standard coordinate sys-
tem increase from bottom to top.

The W2 array allows the definition of vertical metrics for individual CIDs. The
elements of the array are organized in groups of two or five, where each group is
in one of the following two formats:

  c [ w11y v1x v1y w12y v2x v2y … ]
  cfirst clast w11y v1x v1y

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