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            CHAPTER 5                                                                                    Text




                                        TABLE 5.2 Text state operators
OPERANDS        OPERATOR       DESCRIPTION

charSpace       Tc             Set the character spacing, Tc , to charSpace, which is a number expressed in un-
                               scaled text space units. Character spacing is used by the Tj, TJ, and ' operators.
                               Initial value: 0.

wordSpace       Tw             Set the word spacing, Tw, to wordSpace, which is a number expressed in unscaled
                               text space units. Word spacing is used by the Tj, TJ, and ' operators. Initial
                               value: 0.

scale           Tz             Set the horizontal scaling, Th , to (scale ÷ 100). scale is a number specifying the
                               percentage of the normal width. Initial value: 100 (normal width).

leading         TL             Set the text leading, Tl , to leading, which is a number expressed in unscaled text
                               space units. Text leading is used only by the T*, ', and " operators. Initial value: 0.

font size       Tf             Set the text font, Tf , to font and the text font size, Tfs , to size. font is the name of a
                               font resource in the Font subdictionary of the current resource dictionary; size is
                               a number representing a scale factor. There is no initial value for either font or
                               size; they must be specified explicitly by using Tf before any text is shown.

render          Tr             Set the text rendering mode, Tmode , to render, which is an integer. Initial value: 0.

rise            Ts             Set the text rise, Trise , to rise, which is a number expressed in unscaled text space
                               units. Initial value: 0.

            Note that some of these parameters are expressed in unscaled text space units.
            This means that they are specified in a coordinate system that is defined by the
            text matrix, Tm but is not scaled by the font size parameter, Tfs .


   5.2.1 Character Spacing

            The character-spacing parameter, Tc , is a number specified in unscaled text space
            units (although it is subject to scaling by the Th parameter if the writing mode is
            horizontal). When the glyph for each character in the string is rendered, Tc is
            added to the horizontal or vertical component of the glyph’s displacement,
            depending on the writing mode. (See Section 5.1.3, “Glyph Positioning and
            Metrics,” for a discussion of glyph displacements.) In the default coordinate sys-
            tem, horizontal coordinates increase from left to right and vertical coordinates
            from bottom to top. Therefore, for horizontal writing, a positive value of Tc has

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