This topic refers to how leading is implemented in Roman composition. For information on leading in CJK text, see About leading in Asian text.

The vertical space between lines of type is called leading. Leading is measured from the baseline of one line of text to the baseline of the line above it. Baseline is the invisible line on which most letters—that is, those without descenders—sit.

The default auto-leading option sets the leading at 120% of the type size (for example, 12‑point leading for 10‑point type). When auto-leading is in use, InCopy displays the leading value in parentheses in the Leading menu of the Character panel.

About leading in Asian text

The basis position for leading can be set through the Leading Basis Position setting in the Paragraph panel menu. With the default setting (Embox Top/Right), the text line leading is measured from the top of its embox to the top of the next line's embox. By selecting the line and increasing the leading value using the Embox top/Right setting, the space between the selected line and the next line will grow, because the direction leading is measured from the current line to the next line. All other Leading Basis Position settings measure leading from the current line to the previous line, so changing the leading amount with those settings will increase the line aki above the current line.

Set leading from Leading in the Character panel or Control panel. This is set to Automatic by default. When Auto Leading is set, the leading value is displayed in parentheses in Leading in the Character panel. This Automatic value varies for text frames and text in frame grids. The Automatic Leading value can be set from the Justification menu item in the Paragraph panel. The default setting for the automatic leading value for text in text frames in InCopy is 175% of the set font size. For text in frame grids, it is 100%, which allows for the grid alignment to spread out the lines of the text in the grid.

When grid alignment is set to None, set text leading in the text frame with the Leading value in the Character panel. When grid alignment is set to anything other than None, leading will be applied according to the baseline grid settings.

To set Leading for text in frame grids use Line Gap in the Frame Grid Settings dialog box instead of the leading value. The leading value for text in the frame grid is the sum of the Line Gap value and the grid size (font size). In other words, if the grid size is 13Q and line gap is 10H, the actual leading value will be "23H".

Note that for text placed in the frame grid, the default grid justification is set to Center. In this case, the value between the grid center and the center of the next grid will be the leading value. When grid justification has been set to None, leading will be applied from the location specified in the grid. When grid justification is set to None, leading will be applied according to the value set in Leading in the Character panel.

Leading within a frame grid is complex. For placed text, the actual leading value changes depending on the Font Size, Leading value and also the Gyoudori settings in the Paragraph panel. Take note of the following:

• If you leave the font size for the frame grid unchanged, but make the font size or leading value of placed text smaller than the grid size in the Character panel, the text will be aligned to the grid according to the Grid Justification settings.

• If you leave the font size (grid size) for a frame grid unchanged but use the Character panel to make the font size of placed text larger than the grid size+line gap, gyoudori will be determined automatically, and you can align to the grid in increments of 0.5 lines, therefore 1.5, 2, 2.5 and 3 and so on if Gyoudori is set to Automatic. If Gyoudori is set to anything other than Automatic, text will be aligned to the grid according to this setting, and for a large font size the characters will overlap.

• If you leave the font size (grid size) of the frame grid unchanged but use the Character panel to set the gyoudori of placed text to a value larger than the grid size+line gap, leading will apply to the next line when leading is set to Automatic. For example, if the frame grid size is 13Q and the line gap is set to 10H, when leading is set to 24H, text will be placed on every other line. If set to 47H, text will be placed on every third line. For any leading setting other than Automatic, the value set in Leading will be ignored.

Change leading

By default, leading is a character attribute, which means that you can apply more than one leading value within the same paragraph. The largest leading value in a line of type determines the leading for that line. However, you can select a preferences option so that leading applies to the entire paragraph, instead of to text within a paragraph. This setting does not affect the leading in existing frames.

Change leading of selected text

If InCopy ignores the leading change, it may be due to Vertical Justification or Align To Baseline Grid being selected. Choose Object > Text Frame Options and make sure Vertical Justification is set to Top, and make sure Do Not Align To Baseline Grid is selected in the Paragraph panel, Control panel, or paragraph style.

Change the default leading percentage

Apply leading to whole paragraphs

Adjust line height based on character proportion

By changing the text orientation in a frame grid to its opposite (for horizontal text, it is vertical; for vertical text, it is horizontal), the line height will be changed by default regardless of the grid size. For example, for 13Q characters placed in a horizontal type 13Q frame grid, when setting the character's vertical proportion to 200%, regardless of grid size, the line height will be doubled and become 26Q. If this function is turned off, the line height will be the same as the character height and only the character proportion will be changed.

To disable this feature, select the text for which the feature was enabled, and reselect Adjust Line Height with Character Scale from the Character panel menu or Control panel menu, and turn it off.

Apply the leading basis position

If you set grid alignment to None, leading is applied from the top or right of the embox of the current line to the top or right of the embox of the next line by default. Increasing the leading value causes the new value to be applied to all selected lines.

To set even leading regardless of font size, you can use Embox Center to set leading from the center of the line.

Leading Basis Position options

From Leading Basis Position in the Paragraph panel menu or Control panel menu, select from the following options for leading basis.

Leading will be based on the top of the embox for horizontal type or on the right of the embox for vertical type. Leading is measured from the top or right of the current line to the top or right of the next line. These settings are the default settings.

Leading will be based from the center of the current line to the center of the previous line. If different font sizes exist within the same paragraph, the space between the embox edges of each line will be uneven. When Embox Center is selected, by setting fixed leading for text with differing font sizes, you can align line spacing for surrounding lines because leading will occur based on the center of the current embox.

Leading occurs based on the Roman Baseline. Leading is measured from the baseline of the current line to the baseline of the previous line. This leading method is the same as that which is used in the Roman composer. The Roman Baseline is different for each font. The character position may vary even within the same font size if the fonts are different.

Leading occurs based from the bottom of the embox for horizontal type or from the left of the embox for vertical type. Leading is measured from the left or bottom of the current line to the left or bottom of the previous line.