PDF Format Reference - Adobe Portable Document Format

CHAPTER 5

392

Text

Other graphical effects can be achieved by treating the glyph outline as a path in-

stead of filling it. The

text rendering mode

parameter in the graphics state speci-

fies whether glyph outlines are to be filled, stroked, used as a clipping boundary,

or some combination of these effects. (This parameter does not apply to Type 3

fonts.)

operator sets the

text rendering mode to 1 (stroke). The

operator sets the line width to 2 units in

user space. Given those graphics state parameters, the

operator strokes the

glyph outlines with a line 2 points thick (see Figure 5.2).

Example 5.4

/F13 48 Tf

20 38 Td

1 Tr

2 w

( ABC ) Tj

ABC

FIGURE 5.2

Glyph outlines treated as a stroked path

operator

sets the text rendering mode to 7 (clip), causing the subsequent

operator to

impose the glyph outlines as the current clipping path. All subsequent painting

operations mark the page only within this path, as illustrated in Figure 5.3. This

state persists until some earlier clipping path is reinstated by the

operator.