tdf#45589 sw: create and paint text portions for bookmarks

Add a new SwBookmarkPortion, derived from SwControlCharPortion.

There is no character for the bookmark in the text so the portion has
length of 0, which makes things quite a bit more tricky.

Formatting:

* SwBookmarkPortion is created last in WhichFirstPortion().

* In an empty paragraph the SwTextFrame::FormatEmpty() must be disabled.

* If there's a bookmark at the end of a paragraph,
SwTextFormatter::CalcAscent() must use the font of the previous
character, not the paragraph font, because that could grow the line
if it's higher.

* The SwMultiPortion complicates matters, because it uses a nested
SwTextFormatInfo and thus we need some extra steps to prevent
duplicate SwBookmarkPortions; this is particluarly a problem for
rotated text portions.
- SwTextFormatter::BuildPortions() must advance the outer
SwTextFormatInfo's bookmark position because BuildMultiPortion() has
already created the SwBookmarkPortion.
- If a SwBookmarkPortion is at the start of a SwMultiPortion, it will
be created before the SwMultiPortion but must be painted inside the
SwMultiPortion because its font is going to be initialised as inside
the SwMultiPortion (e.g. it will be rotated) so its position must
also be adapted to be inside, and only
SwTextPainter::PaintMultiPortion() does the setup for that; add a
hack to move it in SwTextFormatter::BuildMultiPortion().

Painting:

* Using the original font seems rather difficult, hard to predict what
some character is going to look like, and how it scales if the size is
increased; use OpenSymbol instead.  Unfortunately OpenSymbol doesn't
have a good glyph that could be used for both the end of a bookmark
and start of another bookmark at the same position.

* SwLinePortion::PrePaint() wants to avoid moving the portion
half-outside the frame but often it looks better that way (previously
it was misaligned, now it's half-outside).

* Not sure if it makes sense to draw a field shading in
SwTextPaintInfo::DrawViewOpt() too; let's try it out, but dependent on
the same IsViewMetaChars() setting as the bookmark character itself,
not on the field shading setting.

Change-Id: I1ab94afb417221e278dbb3afd6c978a05fc78497
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/87364
Reviewed-by: Michael Stahl <michael.stahl@cib.de>
Tested-by: Michael Stahl <michael.stahl@cib.de>

0 files changed, 0 insertions, 0 deletions