The RichEditWndProc_common function is big enough already by handling
all the window messages, so moving code to handle a message to its own
function makes the code more readable.
There is no reason for the rich text format parser to need a handle to
the window, and even if there were it has a handle to the editor which
contains a handle to the window. It is better to remove this
considering we need to cut down on the use of window handles to
implement windowless richedit controls.
The vertical scrollbar state is stored internally within the control,
so should be used when possible. This will become more necessary when
windowless richedit controls are implemented, and there will no hWnd
to pass to GetScrollInfo.
Comparing the editor as apposed to the handle to the window will work
just as well right now, but will also work when there is no window
handle to make a comparison with, which will be the case with
windowless richedit controls.
The code for the ME_EnsureVisible function does exactly what
EM_SCROLLCARET does, yet this code is duplicated in order to handle
this message. It is simpler to just use the existing function to
implement the message, and avoid internally sending the EM_SCROLLCARET
when this function is available.
For some reason EM_POSFROMCHAR was returning 0 when the position was
equal to the end of the text, or beyond the end of the text. Instead
it should use the position at the end of the text for both these
cases. The x value was also seen to be offset by 1 according to the
tests.
Previously the control words in skipped groups were being processed by
the read hook on the RTF parser. By moving this code into the class
callbacks for the parser, the skipped groups actually remain skipped.
For simple tables cells are represented with tabs, and a table row is
ended at the end of the paragraph, so native richedit controls
substitute spaces for \tab and \par rich text format control words.
The values returned by EM_SETPARAFORMAT and EM_GETPARAFORMAT previously
indicated an error, and the included tests shows that Windows behaves as
documented.
The problem was that the paragraph format was being retrieved,
slightly modified and then used to set the paragraph format, without
limiting the mask to what was being set. The PFM_OFFSETINDENT mask flag
being valid meant that dxStartIndent specifies a relative offset, thus
dxStartIndent was doubled.
When the cursor is moved over the selection bar, without holding any
mouse buttons down, the cursor would be repeatably set between the
normal cursor, set by DefWindowProc for the WM_SETCURSOR message, and
the reversed cursor, set by ME_MouseMove.
I created a function to set the default paragraph format to ensure
consistency when this is done. This initial paragraph format is also
now more consistent with native richedit controls. The dwMask value
always appears to have the same value when retrieved from the native
richedit controls, so all the mask values are now initialized when the
PARAFORMAT2 structure is created.