More case of searching for the paragraph through the linked list when
is was already previously available. Since each wrap context is used
for wrapping each paragraph, I decided to add the reference to the
paragarph in the structure.
The width for EM_SETTARGETDEVICE is used by some applications to set the
wrapping width to a certain distance in twips. This can be used even
though the target device is ignored.
The methods in ITextHost are mostly thin wrappers around functions that
take a handle to a window as their first parameter. This patch just
uses the wrapper functions provided by ITextHost instead of using the
functions that require a handle to a window that the editor might now
have (for windowless richedit controls).
When the text is wrapped, the positions for all the runs, paragraphs,
and cells are already calculated and stored. The only thing left to do
for painting is to offset them by the formatting rectangle and the
scroll position.
During wrapping there were three different heights that were being
stored, with only one of them being done correctly. The other ones
failed to incorporate the height of the paragraph or row, so ended up
being incorrect.
The formatting rectangle is set with EM_SETRECT, and retrieved with
EM_GETRECT, so it corresponds to rcFormat in the code. This defines the
area that the richedit control should draw the text so that it is
offset by the top-left corner of the formatting rectangle, and clipped
so that it doesn't draw past the bottom or right hand side. Thus this
is important for implementing windowless richedit controls to not
interfere with the rest of the window.
The assertion was not valid, because it neglected to take into account
the situation where a line break is forced with a MERF_ENDROW run
(caused by \line control word or pressing Shift-Enter). This means
that spaces can cause a line wrap after a forced line break as well as
after a paragraph break, so we cannot assert that it is the first row
in the paragraph.
The uncommon case that this patch handles is enough whitespace being
on the first line of a paragraph to cause it to wrap. In this case the
first non-space character will be wrapped onto the next line.
