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SECTION 5.2                                      Text State Param eters and Operators




                          TABLE 5.1 Text state parameters
PARAMETER            DESCRIPTION

Tc                   Character spacing

Tw                   Word spacing

Th                   Horizontal scaling

Tl                   Leading

Tf                   Text font

Tfs                  Text font size

Tmode                Text rendering mode

Trise                Text rise

Tk                   Text knockout

Except for the self-explanatory Tf and Tfs , these parameters are discussed further
in the following sections. (As described in Section 5.3, “Text Objects,” three addi-
tional text-related parameters are defined only within a text object: Tm , the text
matrix; Tlm , the text line matrix; and Trm , the text rendering matrix.) The values
of the text state parameters are consulted when text is positioned and shown
(using the operators described in Sections 5.3.1, “Text-Positioning Operators,”
and 5.3.2, “Text-Showing Operators”). In particular, the spacing and scaling
parameters participate in a computation described in Section 5.3.3, “Text Space
Details.” The text state parameters can be set using the operators listed in Table
5.2.

Note: The text knockout parameter, Tk , is set through the TK entry in a graphics
state parameter dictionary by using the gs operator (see Section 4.3.4, “Graphics
State Parameter Dictionaries”). There is no specific operator for setting this parame-
ter.

The text state operators can appear outside text objects, and the values they set
are retained across text objects in a single content stream. Like other graphics
state parameters, these parameters are initialized to their default values at the
beginning of each page.

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