17.5.11 Specifying DocBook element levels
Generally speaking, you should not specify element levels unless there really is no other way to properly nest an element; hard-coded levels can cause obscure damage to the output.
To specify the level at which a block element should appear in DocBook output, you can assign a level number to any FrameMaker paragraph formats that are mapped to the element (see §17.4.2 Mapping paragraph formats to DocBook elements). However, for most nesting issues, you should use settings that specify ancestry rather than level; see §17.5.2 Designating DocBook ancestor elements. Assign levels only for the following purposes:
• to identify paragraph formats mapped to <title> that should start new topics; assign level 1 to each such format
• to handle unusual situations that cannot be addressed any other way.
To specify the level of a DocBook block element:
; Frame para format (wildcards OK) = level in DocBook (not Frame) file
; required for the DocBookParaTag specified for this element.
The lower the level number, the higher the level; <set> is level 0, the root. You cannot put anything else at level 0. The set title is at level 1. The first book title in the set is at level 2 (a title below <set> and <book>).
In this example the element levels would be <body> = 1, <section> = 2, the title under <topic> (mapped implicitly from paragraph format Title) = 1, and any title under <section> (mapped explicitly from a Heading1 format) = 3. GlossItem is assigned level 1 because this format is mapped to <glossterm>, which is the first element in a glossary topic (equivalent to <title> in other topic types).
To override the assigned level of a particular paragraph, place a DocBookLevel marker in the paragraph. A DocBookLevel marker specifies the level at which the current block element should appear in the DocBook file, overriding whatever is specified for the format in [DocBookLevels]. The content of a DocBookLevel marker is a single integer.
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