What is the point of leading override?

[mogsie]

I didn't do it on purpose, but by accident. And it makes me nervous because it doesn't show up in the context bar. If it had been less of a change, and hadn't looked so horrible, I would have missed it altogether.

[thomaso]

2 hours ago, mogsie said:

it makes me nervous because it doesn't show up in the context bar.

Only very few of all text style properties are displayed in the Context Toolbar, a large majority is not shown there but in the panels or the 'Edit Text Style' window only, and some of them can even get influenced also in the Text Frame panel (for instance "Indent" vs. "Insets" / "Baseline Shift" vs. "Vertical Position" / "Baseline Grid" vs. "Baseline Grid").

What may seem confusing is on the other hand a useful flexibility that allows us to combine certain settings with others, while allowing us to influence/achieve a specific hierarchy for certain settings with desired dependencies between styles or style properties.

3 hours ago, mogsie said:

If it had been less of a change, and hadn't looked so horrible, I would have missed it altogether.

Actually, for many designs it is possible to use "Leading Override" only and ignore "paragraph leading" without running into visual issues. Its consequence is not necessarily a "horrible look" (while that can also happen with many accidental settings and without the use of "Leading Override"). Nevertheless a preferred, proper use of paragraph leading with an only selective, specific use of character options like "Leading Override" or "Baseline Shift" gives more flexibility and reliability, not only in the Context Toolbar's info.

For style creation it may be easier to use the two panels (char. / par.) only since they seem to allow the best visual overview with their various collapsible sub-sections whereas style properties in the "Edit Text Style" dialog window (via the Text Style panel) may be harder to control and give less overview. This window is more useful to edit just a certain property of a saved style or to create a new style based on another, existing saved style.

[lacerto]

I think that overrides from underlying styles are by design only shown in context of the Text Styles panel (shown by using a plus sign) -- I do not think that showing a plus sign in controls themselves (like the Paragraph Leading box on context toolbar) would help in avoiding confusion caused by complexity of the feature itself (which IMO behaves logically and as designed [EDIT: though it is an interesting question whether the Paragraph box should show the style-defined paragraph leading which has not been applied, or the actual leading based on original paragraph leading]. The following clip shows what happens when the style definition is applied in a copy of the text passage, clearing the overrides that are left in the upper version and thus applying the style definition, where the original 12pt paragraph leading and font size has been redefined by using a local character-based leading and font size:

 To demonstrate what I meant in my earlier post when referring to IDML compatibility, here is how QuarkXPress 2018, which does not support (at least in this version; the later versions that support also IDML export might do) character-based leading overrides, at all. renders (incorrectly) the same IDML imported text shown above in the video, demonstrating that Affinity Publisher renders the text identically with InDesign. The same effect could of course be achieved in QuarkXpress, too, by using workarounds like local baseline shift, etc..

 

QuarkXPress, on the other hand, supports leading-related features and finesse not available in InDesign and Affinity Publisher. I do not think that any of these apps does leading "correctly" or "incorrectly", they just implement a complex feature differently (e.g., InDesign does not basically support paragraph based leading as a direct attribute and UI control, at all, but just as an option that when applied disables character based leading overrides).